Table of content

BMC Infectious Diseases

ISSN/EISSN: 14712334
Subject: Internal medicine
Publisher: BioMed Central
Country: United Kingdom
Language: English
Start year 2001
Publication fee: Yes --- Further Information

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Table of content: 2005 volume:5 issue:1

Article
Toxicity after prolonged (more than four weeks) administration of intravenous colistin

Authors: Falagas Matthew E --- Rizos Michael --- Bliziotis Ioannis A --- Rellos Kostas --- et al.
DOI: 10.1186/1471-2334-5-1
Pages: 1
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Abstract

Abstract

Background

The intravenous use of polymyxins has been considered to be associated with considerable nephrotoxicity and neurotoxicity. For this reason, the systemic administration of polymyxins had been abandoned for about 20 years in most areas of the world. However, the problem of infections due to multidrug-resistant (MDR) Gram-negative bacteria such us Pseudomonas aeruginosa and Acinetobacter baumanniii has led to the re-use of polymyxins. Our objective was to study the toxicity of prolonged intravenous administration of colistin (polymyxin E).

Methods

An observational study of a retrospective cohort at "Henry Dunant" Hospital, a 450-bed tertiary care center in Athens, Greece, was undertaken.

Patients who received intravenous colistin for more than 4 weeks for the treatment of multidrug resistant Gram-negative infections were included in the study. Serum creatinine, blood urea, liver function tests, symptoms and signs of neurotoxicity were the main outcomes studied.

Results

We analyzed data for 19 courses of prolonged intravenous colistin [mean duration of administration (± SD) 43.4 (± 14.6) days, mean daily dosage (± SD) 4.4 (± 2.1) million IU, mean cumulative dosage (± SD) 190.4 (± 91.0) million IU] in 17 patients. The median creatinine value increased by 0.25 mg/dl during the treatment compared to the baseline (p < 0.001) but returned close to the baseline at the end of treatment (higher by 0.1 mg/dl, p = 0.67). No apnea or other evidence of neuromuscular blockade was noted in any of these patients who received prolonged treatment with colistin.

Conclusions

No serious toxicity was observed in this group of patients who received prolonged intravenous colistin. Colistin should be considered as a therapeutic option in patients with infections due to multidrug resistant Gram-negative bacteria.

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Article
Substituting abacavir for hyperlipidemia-associated protease inhibitors in HAART regimens improves fasting lipid profiles, maintains virologic suppression, and simplifies treatment

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Abstract

Abstract

Background

Hyperlipidemia secondary to protease inhibitors (PI) may abate by switching to anti-HIV medications without lipid effects.

Method

An open-label, randomized pilot study compared changes in fasting lipids and HIV-1 RNA in 104 HIV-infected adults with PI-associated hyperlipidemia (fasting serum total cholesterol >200 mg/dL) who were randomized either to a regimen in which their PI was replaced by abacavir 300 mg twice daily (n = 52) or a regimen in which their PI was continued (n = 52) for 28 weeks. All patients had undetectable viral loads (HIV-1 RNA <50 copies/mL) at baseline and were naïve to abacavir and non-nucleoside reverse transcriptase inhibitors.

Results

At baseline, the mean total cholesterol was 243 mg/dL, low density lipoprotein (LDL)-cholesterol 149 mg/dL, high density lipoprotein (HDL)-cholesterol 41 mg/dL, and triglycerides 310 mg/dL. Mean CD4+ cell counts were 551 and 531 cells/mm3 in the abacavir-switch and PI-continuation arms, respectively. At week 28, the abacavir-switch arm had significantly greater least square mean reduction from baseline in total cholesterol (-42 vs -10 mg/dL, P < 0.001), LDL-cholesterol (-14 vs +5 mg/dL, P = 0.016), and triglycerides (-134 vs -36 mg/dL, P = 0.019) than the PI-continuation arm, with no differences in HDL-cholesterol (+0.2 vs +1.3 mg/dL, P = 0.583). A higher proportion of patients in the abacavir-switch arm had decreases in protocol-defined total cholesterol and triglyceride toxicity grades, whereas a smaller proportion had increases in these toxicity grades. At week 28, an intent-to treat: missing = failure analysis showed that the abacavir-switch and PI-continuation arms did not differ significantly with respect to proportion of patients maintaining HIV-1 RNA <400 or <50 copies/mL or adjusted mean change from baseline in CD4+ cell count. Two possible abacavir-related hypersensitivity reactions were reported. No significant changes in glucose, insulin, insulin resistance, C-peptide, or waist-to-hip ratios were observed in either treatment arm, nor were differences in these parameters noted between treatments.

Conclusion

In hyperlipidemic, antiretroviral-experienced patients with HIV-1 RNA levels <50 copies/mL and CD4+ cell counts >500 cells/mm3, substituting abacavir for hyperlipidemia-associated PIs in combination antiretroviral regimens improves lipid profiles and maintains virologic suppression over a 28-week period, and it simplifies treatment.

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Article
Enterococcal meningitis caused by Enterococcus casseliflavus. First case report

Authors: Iaria Chiara --- Stassi Giovanna --- Costa Gaetano --- Di Leo Rita --- et al.
DOI: 10.1186/1471-2334-5-3
Pages: 3
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Abstract

Abstract

Background

Enterococcal meningitis is an uncommon disease usually caused by Enterococcus faecalis and Enterococcus faecium and is associated with a high mortality rate. Enterococcus casseliflavus has been implicated in a wide variety of infections in humans, but never in meningitis.

Case presentation

A 77-year-old Italian female presented for evaluation of fever, stupor, diarrhea and vomiting of 3 days duration. There was no history of head injury nor of previous surgical procedures. She had been suffering from rheumatoid arthritis for 30 years, for which she was being treated with steroids and methotrexate. On admission, she was febrile, alert but not oriented to time and place. Her neck was stiff, and she had a positive Kernig's sign. The patient's cerebrospinal fluid was opalescent with a glucose concentration of 14 mg/dl, a protein level of 472 mg/dl, and a white cell count of 200/μL with 95% polymorphonuclear leukocytes and 5% lymphocytes. Gram staining of CSF revealed no organisms, culture yielded E. casseliflavus. The patient was successfully treated with meropenem and ampicillin-sulbactam.

Conclusions

E. casseliflavus can be inserted among the etiologic agents of meningitis. Awareness of infection of central nervous system with Enterococcus species that possess an intrinsic vancomycin resistance should be increased.

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Article
Viability testing of material derived from Mycobacterium tuberculosis prior to removal from a Containment Level-III Laboratory as part of a Laboratory Risk Assessment Program

Authors: Blackwood Kym S --- Burdz Tamara V --- Turenne Christine Y --- Sharma Meenu K --- et al.
DOI: 10.1186/1471-2334-5-4
Pages: 4
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Abstract

Abstract

Background

In the field of clinical mycobacteriology, Mycobacterium tuberculosis (MTB) can be a difficult organism to manipulate due to the restrictive environment of a containment level 3 (CL3) laboratory. Tests for rapid diagnostic work involving smears and molecular methods do not require CL3 practices after the organism has been rendered non-viable. While it has been assumed that after organism deactivation these techniques can be performed outside of a CL3, no conclusive study has consistently confirmed that the organisms are noninfectious after the theoretical 'deactivation' steps. Previous studies have shown that initial steps (such as heating /chemical fixation) may not consistently kill MTB organisms.

Methods

An inclusive viability study (n = 226) was undertaken to determine at which point handling of culture extraction materials does not necessitate a CL3 environment. Four different laboratory protocols tested for viability included: standard DNA extractions for IS6110 fingerprinting, crude DNA preparations for PCR by boiling and mechanical lysis, protein extractions, and smear preparations. For each protocol, laboratory staff planted a proportion of the resulting material to Bactec 12B medium that was observed for growth for 8 weeks.

Results

Of the 208 isolates initially tested, 21 samples grew within the 8-week period. Sixteen (7.7%) of these yielded positive results for MTB that included samples of: deactivated culture resuspensions exposed to 80°C for 20 minutes, smear preparations and protein extractions. Test procedures were consequently modified and tested again (n = 18), resulting in 0% viability.

Conclusions

This study demonstrates that it cannot be assumed that conventional practices (i.e. smear preparation) or extraction techniques render the organism non-viable. All methodologies, new and existing, should be examined by individual laboratories to validate the safe removal of material derived from MTB to the outside of a CL3 laboratory. This process is vital to establish in house biosafety-validated practices with the aim of protecting laboratory workers conducting these procedures.

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Article
Daily antibiotic cost of nosocomial infections in a Turkish university hospital

Authors: Inan Dilara --- Saba Rabin --- Gunseren Filiz --- Ongut Gozde --- et al.
DOI: 10.1186/1471-2334-5-5
Pages: 5
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Abstract

Abstract

Background

Many studies associated nosocomial infections with increased hospital costs due to extra days in hospital, staff time, extra investigations and drug treatment. The cost of antibiotic treatment for these infections represents a significant part of hospital expenditure. This prospective observational study was designed to determine the daily antibiotic cost of nosocomial infections per infected adult patient in Akdeniz University Hospital.

Methods

All adult patients admitted to the ICUs between January 1, 2000, and June 30, 2003 who had only one nosocomial infection during their stay were included in the study. Infection sites and pathogens, antimicrobial treatment of patient and it's cost were recorded. Daily antibiotic costs were calculated per infected patient.

Results

Among the 8460 study patients, 817 (16.6%) developed 1407 episodes of nosocomial infection. Two hundred thirty three (2.7%) presented with only one nosocomial infection. Mean daily antibiotic cost was $89.64. Daily antibiotic cost was $99.02 for pneumonia, $94.32 for bloodstream infection, $94.31 for surgical site infection, $52.37 for urinary tract infection, and $162.35 for the other infections per patient. The treatment of Pseudomonas aeruginosa infections was the most expensive infection treated. Piperacillin-tazobactam and amikacin were the most prescribed antibiotics, and meropenem was the most expensive drug for treatment of the nosocomial infections in the ICU.

Conclusions

Daily antibiotic cost of nosocomial infections is an important part of extra costs that should be reduced providing rational antibiotic usage in hospitals.

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Article
A novel pancoronavirus RT-PCR assay: frequent detection of human coronavirus NL63 in children hospitalized with respiratory tract infections in Belgium

Authors: Moës Elien --- Vijgen Leen --- Keyaerts Els --- Zlateva Kalina --- et al.
DOI: 10.1186/1471-2334-5-6
Pages: 6
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Abstract

Abstract

Background

Four human coronaviruses are currently known to infect the respiratory tract: human coronaviruses OC43 (HCoV-OC43) and 229E (HCoV-229E), SARS associated coronavirus (SARS-CoV) and the recently identified human coronavirus NL63 (HCoV-NL63). In this study we explored the incidence of HCoV-NL63 infection in children diagnosed with respiratory tract infections in Belgium.

Methods

Samples from children hospitalized with respiratory diseases during the winter seasons of 2003 and 2004 were evaluated for the presence of HCoV-NL63 using a optimized pancoronavirus RT-PCR assay.

Results

Seven HCoV-NL63 positive samples were identified, six were collected during January/February 2003 and one at the end of February 2004.

Conclusions

Our results support the notation that HCoV-NL63 can cause serious respiratory symptoms in children. Sequence analysis of the S gene showed that our isolates could be classified into two subtypes corresponding to the two prototype HCoV-NL63 sequences isolated in The Netherlands in 1988 and 2003, indicating that these two subtypes may currently be cocirculating.

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Article
International outbreak of Salmonella Oranienburg due to German chocolate

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Abstract

Abstract

Background

This report describes a large international chocolate-associated Salmonella outbreak originating from Germany.

Methods

We conducted epidemiologic investigations including a case-control study, and food safety investigations. Salmonella (S.) Oranienburg isolates were subtyped by the use of pulsed-field gel electrophoresis (PFGE).

Results

From 1 October 2001 through 24 March 2002, an estimated excess of 439 S. Oranienburg notifications was registered in Germany. Simultaneously, an increase in S. Oranienburg infections was noted in other European countries in the Enter-net surveillance network. In a multistate matched case-control study in Germany, daily consumption of chocolate (matched odds ratio [MOR]: 4.8; 95% confidence interval [CI]: 1.3–26.5), having shopped at a large chain of discount grocery stores (MOR: 4.2; CI: 1.2–23.0), and consumption of chocolate purchased there (MOR: 5.0; CI: 1.1–47.0) were associated with illness. Subsequently, two brands from the same company, one exclusively produced for that chain, tested positive for S. Oranienburg. In two other European countries and in Canada chocolate from company A was ascertained that also contained S. Oranienburg. Isolates from humans and from chocolates had indistinguishable PFGE profiles. No source or point of contamination was identified. Epidemiological identification of chocolate as a vehicle of infections required two months, and was facilitated by proxy measures.

Conclusions

Despite the use of improved production technologies, the chocolate industry continues to carry a small risk of manufacturing Salmonella-containing products. Particularly in diffuse outbreak-settings, clear associations with surrogates of exposure should suffice to trigger public health action. Networks such as Enter-net have become invaluable for facilitating rapid and appropriate management of international outbreaks.

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Article
Detection of virulence genes in Malaysian Shigella species by multiplex PCR assay

Authors: Thong Kwai --- Hoe Susan --- Puthucheary SD --- Md Yasin Rohani
DOI: 10.1186/1471-2334-5-8
Pages: 8
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Abstract

Abstract

Background

In Malaysia, Shigella spp. was reported to be the third commonest bacterial agent responsible for childhood diarrhoea. Currently, isolation of the bacterium and confirmation of the disease by microbiological and biochemical methods remain as the "gold standard". This study aimed to detect the prevalence of four Shigella virulence genes present concurrently, in randomly selected Malaysian strains via a rapid multiplex PCR (mPCR) assay.

Methods

A mPCR assay was designed for the simultaneous detection of chromosomal- and plasmid-encoded virulence genes (set1A, set1B, ial and ipaH) in Shigella spp. One hundred and ten Malaysian strains (1997–2000) isolated from patients from various government hospitals were used. Reproducibility and sensitivity of the assay were also evaluated. Applicability of the mPCR in clinical settings was tested with spiked faeces following preincubation in brain heart infusion (BHI) broth.

Results

The ipaH sequence was present in all the strains, while each of the set1A, set1B and ial gene was present in 40% of the strains tested. Reproducibility of the mPCR assay was 100% and none of the non-Shigella pathogens tested in this study were amplified. The mPCR could detect 100 colony-forming units (cfu) of shigellae per reaction mixture in spiked faeces following preincubation.

Conclusions

The mPCR system is reproducible, sensitive and is able to identify pathogenic strains of shigellae irrespective of the locality of the virulence genes. It can be easily performed with a high throughput to give a presumptive identification of the causal pathogen.

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Article
CNS activity of Pokeweed Anti-viral Protein (PAP) in mice infected with Lymphocytic Choriomeningitis Virus (LCMV)

Authors: Uckun Fatih M --- Rustamova Larisa --- Vassilev Alexei O --- Tibbles Heather E --- et al.
DOI: 10.1186/1471-2334-5-9
Pages: 9
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Abstract

Abstract

Background

Others and we have previously described the potent in vivo and in vitro activity of the broad-spectrum antiviral agent PAP (Pokeweed antiviral protein) against a wide range of viruses. The purpose of the present study was to further elucidate the anti-viral spectrum of PAP by examining its effects on the survival of mice challenged with lymphocytic choriomeningitis virus (LCMV).

Methods

We examined the therapeutic effect of PAP in CBA mice inoculated with intracerebral injections of the WE54 strain of LCMV at a 1000 PFU dose level that is lethal to 100% of mice within 7–9 days. Mice were treated either with vehicle or PAP administered intraperitoneally 24 hours prior to, 1 hour prior to and 24 hours, 48 hours 72 hours and 96 hours after virus inoculation.

Results

PAP exhibits significant in vivo anti- LCMV activity in mice challenged intracerebrally with an otherwise invariably fatal dose of LCMV. At non-toxic dose levels, PAP significantly prolonged survival in the absence of the majority of disease-associated symptoms. The median survival time of PAP-treated mice was >21 days as opposed to 7 days median survival for the control (p = 0.0069).

Conclusion

Our results presented herein provide unprecedented experimental evidence that PAP exhibits antiviral activity in the CNS of LCMV-infected mice.

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Article
Emergency vaccination of rabies under limited resources – combating or containing?

Authors: Eisinger Dirk --- Thulke Hans-Hermann --- Selhorst Thomas --- Müller Thomas
DOI: 10.1186/1471-2334-5-10
Pages: 10
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Abstract

Abstract

Background

Rabies is the most important viral zoonosis from a global perspective. Worldwide efforts to combat the disease by oral vaccination of reservoirs have managed to eradicate wildlife rabies in large areas of central Europe and North-America. Thus, repeated vaccination has been discontinued recently on a geographical scale. However, as rabies has not yet been eradicated globally, a serious risk of re-introduction remains. What is the best spatial design for an emergency vaccination program – particularly if resources are limited? Either, we treat a circular area around the detected case and run the risk of infected hosts leaving the limited control area, because a sufficient immunisation level has not yet been built up. Or, initially concentrate the SAME resources in order to establish a protective ring which is more distant from the infected local area, and which then holds out against the challenge of the approaching epidemic.

Methods

We developed a simulation model to contrast the two strategies for emergency vaccination. The spatial-explicit model is based on fox group home-ranges, which facilitates the simulation of rabies spread to larger areas relevant to management. We used individual-based fox groups to follow up the effects of vaccination in a detailed manner. Thus, regionally – bait distribution orientates itself to standard schemes of oral immunisation programs and locally – baits are assigned to individual foxes.

Results

Surprisingly, putting the controlled area ring-like around the outbreak does not outperform the circular area of the same size centred on the outbreak. Only during the very first baitings, does the ring area result in fewer breakouts. But then as rabies is eliminated within the circle area, the respective ring area fails, due to the non-controlled inner part.

We attempt to take advantage of the initially fewer breakouts beyond the ring when applying a mixed strategy. Therefore, after a certain number of baitings, the area under control was increased for both strategies towards the same larger circular area. The circle-circle strategy still outperforms the ring-circle strategy and analysis of the spatial-temporal disease spread reveals why: improving control efficacy by means of a mixed strategy is impossible in the field, due to the build-up time of population immunity.

Conclusion

For practical emergency management of a new outbreak of rabies, the ring-like application of oral vaccination is not a favourable strategy at all. Even if initial resources are substantially low and there is a serious risk of rabies cases outside the limited control area, our results suggest circular application instead of ring vaccination.

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Article
Could flies explain the elusive epidemiology of campylobacteriosis?

Authors: Ekdahl Karl --- Normann Bengt --- Andersson Yvonne
DOI: 10.1186/1471-2334-5-11
Pages: 11
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Abstract

Abstract

Background

Unlike salmonellosis with well-known routes of transmission, the epidemiology of campylobacteriosis is still largely unclear. Known risk factors such as ingestion of contaminated food and water, direct contact with infected animals and outdoor swimming could at most only explain half the recorded cases.

Discussion

We put forward the hypothesis that flies play a more important role in the transmission of the bacteria, than has previously been recognized. Factors supporting this hypothesis are: 1) the low infective dose of Campylobacter; 2) the ability of flies to function as mechanical vectors; 3) a ubiquitous presence of the bacteria in the environment; 4) a seasonality of the disease with summer peaks in temperate regions and a more evenly distribution over the year in the tropics; 5) an age pattern for campylobacteriosis in western travellers to the tropics suggesting other routes of transmission than food or water; and finally 6) very few family clusters.

Summary

All the evidence in favour of the fly hypothesis is circumstantial and there may be alternative explanations to each of the findings supporting the hypothesis. However, in the absence of alternative explanations that could give better clues to the evasive epidemiology of Campylobacter infection, we believe it would be unwise to rule out flies as important mechanical vectors also of this disease.

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Article
Bacterial vaginosis, vaginal flora patterns and vaginal hygiene practices in patients presenting with vaginal discharge syndrome in The Gambia, West Africa

Authors: Demba Edward --- Morison Linda --- van der Loeff Maarten --- Awasana Akum A --- et al.
DOI: 10.1186/1471-2334-5-12
Pages: 12
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Abstract

Abstract

Background

Bacterial vaginosis (BV) – a syndrome characterised by a shift in vaginal flora – appears to be particularly common in sub-Saharan Africa, but little is known of the pattern of vaginal flora associated with BV in Africa. We conducted a study aimed at determining the prevalence of BV and patterns of BV-associated vaginal micro-flora among women with vaginal discharge syndrome (VDS) in The Gambia, West Africa.

Methods

We enrolled 227 women with VDS from a large genito-urinary medicine clinic in Fajara, The Gambia. BV was diagnosed by the Nugent's score and Amsel's clinical criteria. Vaginal swabs were collected for T vaginalis and vaginal flora microscopy, and for Lactobacillus spp, aerobic organisms, Candida spp and BV-associated bacteria (Gardnerella vaginalis, anaerobic bacteria, and Mycoplasma spp) cultures; and cervical swabs were collected for N gonorrhoeae culture and C trachomatis PCR. Sera were tested for HIV-1 and HIV-2 antibodies. Sexual health history including details on sexual hygiene were obtained by standardised questionnaire.

Results

BV prevalence was 47.6% by Nugent's score and 30.8% by Amsel's clinical criteria. Lactobacillus spp were isolated in 37.8% of women, and 70% of the isolates were hydrogen-peroxide (H202)-producing strains. Prevalence of BV-associated bacteria were: G vaginalis 44.4%; Bacteroides 16.7%; Prevotella 15.2%; Peptostretococcus 1.5%; Mobiluncus 0%; other anaerobes 3.1%; and Mycoplasma hominis 21.4%. BV was positively associated with isolation of G vaginalis (odds-ratio [OR] 19.42, 95%CI 7.91 – 47.6) and anaerobes (P = 0.001 [OR] could not be calculated), but not with M hominis. BV was negatively associated with presence of Lactobacillus (OR 0.07, 95%CI 0.03 – 0.15), and H2O2-producing lactobacilli (OR 0.12, 95% CI 0.05 – 0.28). Presence of H2O2-producing lactobacilli was associated with significantly lower prevalence of G vaginalis, anaerobes and C trachomatis. HIV prevalence was 12.8%. Overall, there was no association between BV and HIV, and among micro-organisms associated with BV, only Bacteroides spp. and Prevotella spp. were associated with HIV. BV or vaginal flora patterns were not associated with any of the factors relating to sexual hygiene practices (vaginal douching, menstrual hygiene, female genital cutting).

Conclusion

In this population, BV prevalence was higher than in corresponding populations in industrialised countries, but the pattern of vaginal micro-flora associated with BV was similar. BV or vaginal flora patterns were not associated with HIV nor with any of the vaginal hygiene characteristics.

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Article
A dual fluorescent multiprobe assay for prion protein genotyping in sheep

Authors: Van Poucke Mario --- Vandesompele Jo --- Mattheeuws Marc --- Van Zeveren Alex --- et al.
DOI: 10.1186/1471-2334-5-13
Pages: 13
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Abstract

Abstract

Background

Scrapie and BSE belong to a group of fatal, transmissible, neurodegenerative diseases called TSE. In order to minimize the risk of natural scrapie and presumed natural BSE in sheep, breeding programmes towards TSE resistance are conducted in many countries based on resistance rendering PRNP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (R/H/Q). Therefore, a reliable, fast and cost-effective method for routine PRNP genotyping in sheep, applicable in standard equipped molecular genetic laboratories, will be a vital instrument to fulfill the need of genotyping hundreds or thousands of sheep.

Methods

A dual fluorescent multiprobe assay consisting of 2 closed tube PCR reactions containing respectively 4 and 3 dual-labelled fluorescent ASO probes for the detection in real-time of the 7 allelic variants of sheep PRNP mentioned above.

Results

The assay is succesfully performed using unpurified DNA as a template for PCR, without any post-PCR manipulations and with semi-automatic determination of the PRNP genotypes. The performance of the assay was confirmed via PCR-RFLP and sequencing in a cross-validation study with 50 sheep.

Conclusions

We report the development and validation of a robust, reliable and reproducible method for PRNP genotyping of a few to many sheep samples in a fast, simple and cost-effective way, applicable in standard equipped molecular genetic laboratories. The described primer/probe design strategy can also be applied for the detection of other polymorphisms or disease causing mutations.

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Article
Emergence of unusual species of enterococci causing infections, South India

Authors: Prakash Vittal P --- Rao Sambasiva R --- Parija Subash C
DOI: 10.1186/1471-2334-5-14
Pages: 14
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Abstract

Abstract

Background

Enterococci tend to be one of the leading causes of nosocomial infections, with E. faecalis and E. faecium accounting up to 90% of the clinical isolates. Nevertheless, the incidence of other species of enterococci from clinical sources shows an alarming increase with the properties of intrinsic resistance to several antibiotics including beta-lactams and glycopeptides. Thus proper identification of enterococci to species level is quintessential for management and prevention of these bacteria in any healthcare facility. Hence this work was undertaken to study the prevalence of unusual species of enterococci causing human infections, in a tertiary care hospital in South India.

Methods

The study was conducted in a tertiary care hospital in South India from July 2001 to June 2003. Isolates of enterococci were collected from various clinical specimens and speciated using extensive phenotypic and physiological tests. Antimicrobial susceptibility testing were performed and interpreted as per NCCLS guidelines. Whole cell protein (WCP) fingerprinting of enterococci were done for species validation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and analyzed computationally.

Results

Our study showed the prevalence of unusual (non-faecalis and non-faecium enterococci) and atypical (biochemical variant) species of enterococci as 19% (46 isolates) and 5% (12 isolates) respectively. The 7 unusual species (46 isolates) isolated and confirmed by phenotypic characterization includes: 15 E. gallinarum (6.2%), 10 E. avium (4.1%), 6 E. raffinosus (2.5%), 6 E. hirae (2.5%), 4 E. mundtii (1.7%), 3 E. casseliflavus-including the two atypical isolates (1.2%) and 2 E. durans (0.8%). The 12 atypical enterococcal species (5%) that showed aberrant sugar reactions in conventional phenotyping were confirmed as E. faecalis, E. faecium and E. casseliflavus respectively by WCP fingerprinting. The antimicrobial susceptibility testing depicted the emergence of high-level aminoglycoside and beta-lactam resistance among different species apart from intrinsic vancomycin resistance by some species, while all the species tested were susceptible for linezolid and teicoplanin.

Conclusion

Our study reveals the emergence of multi-drug resistance among unusual species of enterococci posing a serious therapeutic challenge. Precise identification of enterococci to species level enables us to access the species-specific antimicrobial resistance characteristics, apart from knowing the epidemiological pattern and their clinical significance in human infections.

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Article
Human immunodeficiency virus type 1 (HIV-1) proviral DNA load in purified CD4+ cells by LightCycler® Real-time PCR

Authors: Kabamba-Mukadi Benoît --- Henrivaux Philippe --- Ruelle Jean --- Delferrière Nicole --- et al.
DOI: 10.1186/1471-2334-5-15
Pages: 15
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Abstract

Abstract

Background

The human immunodeficiency virus type 1 (HIV-1) proviral DNA persists in infected cells, even after prolonged successful HAART. In the present study, a relative quantification assay of HIV-1 proviral DNA by LightCycler® real-time PCR based on SYBR Green I detection was developed in comparison to the number of purified CD4+ cells as estimated by the quantification of the β-globin gene.

Methods

The ability of the designed gag primers to quantify HIV-1 Group M and the PCR efficiency were assessed on HIV-1 reference isolate subtypes A, B, C and D. The 8E5 cell line containing a single defective copy of HIV-1 proviral DNA was used as a standard for both the HIV-1 target gene and the β-globin reference gene. The assay was applied on thirty consecutive patient samples received for RNA viral load determinations and on retrospective samples from fifteen patients undergoing 2 years of structured treatment interruption (STI).

Results

The lower limit of quantification was 50 HIV-1 DNA proviral copies per CD4+ cell sample. The dynamic range was from 50 to 106 HIV-1 DNA copies per CD4+ cell sample with intra- and inter-assay coefficients of variability ranging from 3.1% to 37.1%. The β-globin reference gene was quantified down to a limit of 1.5 pg of DNA/μl (approximately 5 cells) with intra- and interassay coefficients of variability ranging from 1.8% to 21%. DNA proviral load varies widely among HIV-1 infected patients. Proviral load and plasma viral load rebound were high in STI patients who took longer to achieve an undetectable plasma viral load under therapy. A statistically significant correlation was observed between DNA proviral load and RNA steady state viral load in STI patients (p-value = 0,012).

Conclusion

We have developed a fast, sensitive and specific relative quantification assay of HIV-1 proviral DNA in purified CD4+ cells. The assay enables the monitoring of HIV-1 proviral load, which may be useful to monitor therapy efficacy especially in patients with undetectable plasma RNA viral load, and allows the exploration of viral reservoirs.

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Article
Worldwide trends in quantity and quality of published articles in the field of infectious diseases

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Abstract

Abstract

Background

Trying to confront with the widespread burden of infectious diseases, the society worldwide invests considerably on research. We evaluated the contribution of different world regions in research production in Infectious Diseases.

Methods

Using the online Pubmed database we retrieved articles from 38 journals included in the "Infectious Diseases" category of the "Journal Citation Reports" database of the Institute for Scientific Information for the period 1995–2002. The world was divided into 9 regions based on geographic, economic and scientific criteria. Using an elaborate retrieval system we obtained data on published articles from different world regions. In our evaluation we introduced an estimate of both quantity and quality of research produced from each world region per year using: (1) the total number of publications, (2) the mean impact factor of publications, and (3) the product of the above two parameters.

Results

Data on the country of origin of the research was available for 45,232 out of 45,922 retrieved articles (98.5 %). USA and Western Europe are by far the most productive regions concerning publications of research articles. However, the rate of increase in the production of articles was higher in Eastern Europe, Africa, Latin America and the Caribbean, and Asia during the study period. The mean impact factor is highest for articles originating in the USA (3.42), while it was 2.82 for Western Europe and 2.73 for the rest of the world (7 regions combined).

Conclusion

USA and Western Europe make up a striking 80% of the world's research production in Infectious Diseases in terms of both quantity and quality. However, all world regions achieved a gradual increase in the production of Infectious Diseases articles, with the regions ranking lower at present displaying the highest rate of increase.

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Article
Efficacy of two distinct ethanol-based hand rubs for surgical hand disinfection – a controlled trial according to prEN 12791

Authors: Kampf Günter --- Ostermeyer Christiane
DOI: 10.1186/1471-2334-5-17
Pages: 17
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Abstract

Abstract

Background

Aim of the study was to determine the efficacy of two distinct ethanol-based hand rubs for surgical hand disinfection in a controlled cross-over trial according to prEN 12791.

Methods

20 subjects were included. Hands were washed for 1 min with soap. The bacterial prevalue was obtained by rubbing finger tips in TSB for 1 min. Then, each subject treated the hands with the reference procedure (n-propanol, 60% v/v) or the product (Sterillium® Rub, based on 80% ethanol; Avagard, based on 61% ethanol and 1% chlorhexidine gluconate) which were all applied in 3 to 4 portions each of 3 ml for a total of 3 min. Bacterial postvalues (immediate effect) were taken from one hand, the other hand was gloved for 3 h. After gloves were taken off the second postvalue was taken for the assessment of a sustained effect.

Results

Bacterial pre-values were between 4.38 ± 0.66 and 4.46 ± 0.71. Sterillium® Rub achieved the required immediate (mean log10-reduction of 2.59 ± 1.19) and sustained effect (1.73 ± 1.08) compared with the reference treatment (immediate effect: 2.58 ± 1.16; sustained effect: 1.67 ± 0.96). Avagard, however, did not achieve the required immediate (1.82 ± 1.40) and sustained effect (1.41 ± 1.08) in comparison to the reference disinfection (immediate effect: 2.98 ± 0.90; sustained effect: 2.56 ± 1.17; p < 0.01; Wilcoxon test).

Conclusion

Based on our data, Sterillium® Rub can be regarded to be effective for surgical hand disinfection, but Avagard can not. The addition of 1% chlorhexidine gluconate to 61% ethanol (w/w) did not outweigh an ethanol concentration of 80% (w/w).

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Article
A2 gene of Old World cutaneous Leishmania is a single highly conserved functional gene

Authors: Garin Yves JF --- Meneceur Pascale --- Pratlong Francine --- Dedet Jean-Pierre --- et al.
DOI: 10.1186/1471-2334-5-18
Pages: 18
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Abstract

Abstract

Background

Leishmaniases are among the most proteiform parasitic infections in humans ranging from unapparent to cutaneous, mucocutaneous or visceral diseases. The various clinical issues depend on complex and still poorly understood mechanisms where both host and parasite factors are interacting. Among the candidate factors of parasite virulence are the A2 genes, a family of multiple genes that are developmentally expressed in species of the Leishmania donovani group responsible for visceral diseases (VL). By contrast, in L. major determining cutaneous infections (CL) we showed that A2 genes are present in a truncated form only. Furthermore, the A2 genomic sequences of L. major were considered subsequently to represent non-expressed pseudogenes 1. Consequently, it was suggested that the structural and functional properties of A2 genes could play a role in the differential tropism of CL and VL leishmanias. On this basis, it was of importance to determine whether the observed structural/functional particularities of the L. major A2 genes were shared by other CL Leishmania, therefore representing a proper characteristic of CL A2 genes as opposed to those of VL isolates.

Methods

In the present study we amplified by PCR and sequenced the A2 genes from genomic DNA and from clonal libraries of the four Old World CL species comparatively to a clonal population of L. infantum VL parasites. Using RT-PCR we also amplified and sequenced A2 mRNA transcripts from L. major.

Results

A unique A2 sequence was identified in Old World cutaneous Leishmania by sequencing. The shared sequence was highly conserved among the various CL strains and species analysed, showing a single polymorphism C/G at position 58. The CL A2 gene was found to be functionally transcribed at both parasite stages.

Conclusion

The present study shows that cutaneous strains of leishmania share a conserved functional A2 gene. As opposed to the multiple A2 genes described in VL isolates, the CL A2 gene is unique, lacking most of the nucleotide repeats that constitute the variable region at the 5'end of the VL A2 sequences. As the variable region of the VL A2 gene has been shown to correspond to a portion of the protein which is highly immunogenic, the present results support the hypothesis of a possible role of the A2 gene in the differential tropism of CL and VL leishmania parasites.

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Article
BCG skin reaction in Mantoux-negative healthy children

Authors: Singla Mohit --- Sahai Vaibhav --- Sodhi Sukhbir --- Gupta Rakesh
DOI: 10.1186/1471-2334-5-19
Pages: 19
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Abstract

Abstract

Background

Tuberculosis poses a great challenge, especially in children. The response of BCG Test may be different in previously vaccinated children and needs to be considered before interpreting positivity for TB. This study has been carried out to determine the pattern of BCG reaction comparing previously vaccinated with non-vaccinated children.

Methods

The study was conducted in the healthy school children aged 4–6 years. The BCG skin reaction in Mantoux-negative children was compared between children with and without previous BCG scar. After the Mantoux and BCG Test, the analysis of variance was done as per protocol.

Results

Out of 50 children previously BCG vaccinated, 39(78%) showed exaggerated BCG test responses while out of another 50 children who were not vaccinated for TB, only 9(18%) showed exaggerated BCG Test response (p-value < 0.00001). Average induration obtained in children who were immunized with BCG at birth was much greater than those who were not immunized. 80% and 76% males and females respectively in Group I showed exaggerated BCG response while 16% and 20% males and females respectively of Group II showed exaggerated BCG response.

Conclusion

The present study indicates that normal healthy children may have a mild exaggerated BCG Test response i.e. induration up to 8 mm because of prior BCG vaccination. Therefore, BCG Test, though important should not be the only criteria for start of chemotherapy for TB in children as the side effects of drugs may cause much morbidity. An induration up to 8 mm after the BCG Test can be normal in Indian settings due to exposure to Mycobacterium in environment and/or BCG vaccine.

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Article
Defining the timing of respiratory syncytial virus (RSV) outbreaks: an epidemiological study

Authors: Terletskaia-Ladwig Elena --- Enders Gisela --- Schalasta Gunnar --- Enders Martin
DOI: 10.1186/1471-2334-5-20
Pages: 20
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Abstract

Abstract

Background

Seasonal RSV infections occur every year and affect particularly children under six months of age. Passive immunoprophylaxis with monoclonal antibody Palivizumab is recommended in the period with high risk of RSV infection. This study aims to define the period for the southern part of Germany (Stuttgart area).

Methods

Epidemiological analysis of the RSV situation in southern Germany from 1996 to 2004 and comparison of results with literature was made. The respiratory tract specimens were sent in for the detection of RSV mainly by paediatric clinics. Detection of RSV was carried out mainly by real-time RT-PCR or by ELISA "Pathfinder". RSV outbreaks were depicted as an absolute number and as a percentage of RSV diagnoses in a month. Onsets, offsets, peaks, duration and severity of RSV seasons were defined and analysed.

Results

An early season with strong RSV activity (early-high phase) was followed by a weaker late season (late-low phase) in a regular biennial rhythm. However, onsets, offsets and durations of outbreaks varied significantly from year to year. RSV epidemics in southern Germany were found to oscillate in an antiphase with RSV epidemics in Finland and Sweden.

Conclusion

The long-term regular biennial rhythm allows predicting whether the next outbreak will be late or early and whether RSV activity will be strong or weak. Not foreseeable, however, is the precise time of increase and decrease of RSV activity. Moreover, the regular seasonal pattern may be disrupted by irregular outbreaks. Thus, activity of RSV has to be monitored every year to define the period with high risk of infection.

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Article
Bartonella seropositivity in children with Henoch-Schonlein purpura

Authors: Robinson Joan L --- Spady Donald W --- Prasad Errol --- McColl Dorothy --- et al.
DOI: 10.1186/1471-2334-5-21
Pages: 21
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Abstract

Abstract

Background

An association between Henoch-Schonlein purpura (HSP) and seropositivity for Bartonella henselae (BH) has been described. The objective of this study was to see if such an association exists in northern Alberta.

Methods

Immunofluorescent antibody testing utilizing an antigen prepared from B. henselae was undertaken on sera from six children with current HSP, 22 children with remote HSP, and 28 controls that were matched for age. Blood from the six children with current HSP was analysed by polymerase chain reaction (PCR) assay with primers derived from the citrate synthase (gltA) gene for the detection of Bartonella DNA.

Results

The seropositivity rate for BH was 61% in cases versus 21% in controls (p < 0.03). The PCR assay was negative in all six current cases.

Conclusion

There is an increased seropositivity rate for BH in children with HSP. However, it is not clear if infection with B. henselae or a related Bartonella species can result in HSP, or if the increased seropositivity is from non-specific or cross-reacting antibodies.

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Article
Risk factors for fatal candidemia caused by Candida albicans and non-albicans Candida species

Authors: Cheng Ming-Fang --- Yang Yun-Liang --- Yao Tzy-Jyun --- Lin Chin-Yu --- et al.
DOI: 10.1186/1471-2334-5-22
Pages: 22
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Abstract

Abstract

Background

Invasive fungal infections, such as candidemia, caused by Candida species have been increasing. Candidemia is not only associated with a high mortality (30% to 40%) but also extends the length of hospital stay and increases the costs of medical care. Sepsis caused by Candida species is clinically indistinguishable from bacterial infections. Although, the clinical presentations of the patients with candidemia caused by Candida albicans and non-albicans Candida species (NAC) are indistinguishable, the susceptibilities to antifungal agents of these species are different. In this study, we attempted to identify the risk factors for candidemia caused by C. albicans and NAC in the hope that this may guide initial empiric therapy.

Methods

A retrospective chart review was conducted during 1996 to 1999 at the Veterans General Hospital-Taipei.

Results

There were 130 fatal cases of candidemia, including 68 patients with C. albicans and 62 with NAC. Candidemia was the most likely cause of death in 55 of the 130 patients (42.3 %). There was no significant difference in the distribution of Candida species between those died of candidemia and those died of underlying conditions. Patients who had one of the following conditions were more likely to have C. albicans, age ≧ 65 years, immunosuppression accounted to prior use of steroids, leukocytosis, in the intensive care unit (ICU), and intravascular and urinary catheters. Patients who had undergone cancer chemotherapy often appeared less critically ill and were more likely to have NAC.

Conclusion

Clinical and epidemiological differences in the risk factors between candidemia caused by C. albicans and NAC may provide helpful clues to initiate empiric therapy for patients infected with C. albicans versus NAC.

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Article
Abacavir, efavirenz, didanosine, with or without hydroxyurea, in HIV-infected adults failing initial nucleoside/protease inhibitor-containing regimens

Authors: Swindells Susan --- Cohen Calvin J --- Berger Daniel S --- Tashima Karen T --- et al.
DOI: 10.1186/1471-2334-5-23
Pages: 23
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Abstract

Abstract

Background

Hydroxyurea (HU) is an immunomodulatory agent that has been documented to enhance the antiretroviral activity of nucleoside reverse transcriptase inhibitors, such as abacavir (ABC) and didanosine (ddI), and would be expected to improve virologic efficacy.

Methods

A 48-week, phase IV, multicenter, open-label, proof-of-concept clinical trial was conducted to evaluate second-line, protease inhibitor (PI)-sparing therapy with ABC/efavirenz (EFV)/ddI plus HU or without HU in HIV-infected subjects failing to achieve HIV-1 RNA ≤ 400 copies/mL after ≥ 16 weeks of treatment with lamivudine/zidovudine or lamivudine/stavudine, plus 1 or 2 PIs. Subjects were assigned to ABC (300 mg twice daily)/ EFV (600 mg once daily)/ ddI (400 mg once daily) plus HU (500 mg twice daily) (n = 30) or this regimen without HU (n = 24).

Results

Baseline mean HIV-1 RNA was 3.86 log10 copies/mL and CD4+ cell count was 345 cells/mm3. A similar percentage of subjects in the non-HU arm (58%) and HU arm (53%) completed the study. Intent-to-treat: missing = failure analysis showed no differences in proportions of subjects in the non-HU and HU arms achieving undetectable plasma HIV-1 RNA levels at week 24 (<400 copies/mL: 58% [14/24] vs 57% [17/30], P = 0.899; <50 copies/mL (50% [12/24] vs 47% [14/30], P = 0.780). Median change from baseline in CD4+ cell count in the non-HU and HU arms at week 48 was +114 cells/mm3 and -63 cells/mm3 (P = 0.007), respectively. Both regimens were generally well tolerated, although more subjects in the HU arm withdrew prematurely from the study due to adverse events (23% vs 4%). Four cases of possible ABC-related hypersensitivity were observed.

Conclusion

ABC/EFV/ddI was an effective and well-tolerated second-line regimen for nucleoside/PI-experienced HIV-infected subjects. The addition of HU blunted the CD4+ cell response, did not appear to enhance antiviral activity, and resulted in more treatment-limiting adverse events.

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Article
Outcome of infections due to pandrug-resistant (PDR) Gram-negative bacteria

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Abstract

Abstract

Background

The increasing problem of infections due to multidrug-resistant Gram-negative bacteria has led to re-use of polymyxins in several countries. However, there are already clinical isolates of Gram-negative bacteria that are resistant to all available antibiotics, including polymyxins.

Methods

We present a case series of patients with infections due to pathogens resistant to all antimicrobial agents tested, including polymyxins. An isolate was defined as pandrug-resistant (PDR) if it exhibited resistance to all 7 anti-pseudomonal antimicrobial agents, i.e. antipseudomonal penicillins, cephalosporins, carbapenems, monobactams, quinolones, aminoglycosides, and polymyxins.

Results

Clinical cure of the infection due to pandrug-resistant (PDR) Gram-negative bacteria, namely Pseudomonas aeruginosa or Klebsiella pneumoniae was observed in 4 out of 6 patients with combination of colistin and beta lactam antibiotics.

Conclusion

Colistin, in combination with beta lactam antibiotics, may be a useful agent for the management of pandrug-resistant Gram-negative bacterial infections. The re-use of polymyxins, an old class of antibiotics, should be done with caution in an attempt to delay the rate of development of pandrug-resistant Gram-negative bacterial infections.

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Article
Effective antiprotease-antibiotic treatment of experimental anthrax

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Abstract

Abstract

Background

Inhalation anthrax is characterized by a systemic spread of the challenge agent, Bacillus anthracis. It causes severe damage, including multiple hemorrhagic lesions, to host tissues and organs. It is widely believed that anthrax lethal toxin secreted by proliferating bacteria is a major cause of death, however, the pathology of intoxication in experimental animals is drastically different from that found during the infectious process. In order to close a gap between our understanding of anthrax molecular pathology and the most prominent clinical features of the infectious process we undertook bioinformatic and experimental analyses of potential proteolytic virulence factors of B. anthracis distinct from lethal toxin.

Methods

Secreted proteins (other than lethal and edema toxins) produced by B. anthracis were tested for tissue-damaging activity and toxicity in mice. Chemical protease inhibitors and rabbit immune sera raised against B. anthracis proteases were used to treat mice challenged with B. anthracis (Sterne) spores.

Results

B. anthracis strain delta Ames (pXO1-, pXO2-) producing no lethal and edema toxins secrets a number of metalloprotease virulence factors upon cultivation under aerobic conditions, including those with hemorrhagic, caseinolytic and collagenolytic activities, belonging to M4 and M9 thermolysin and bacterial collagenase families, respectively.

These factors are directly toxic to DBA/2 mice upon intratracheal administration at 0.5 mg/kg and higher doses. Chemical protease inhibitors (phosphoramidon and 1, 10-phenanthroline), as well as immune sera against M4 and M9 proteases of B. anthracis, were used to treat mice challenged with B. anthracis (Sterne) spores. These substances demonstrate a substantial protective efficacy in combination with ciprofloxacin therapy initiated as late as 48 h post spore challenge, compared to the antibiotic alone.

Conclusion

Secreted proteolytic enzymes are important pathogenic factors of B. anthrasis, which can be considered as effective therapeutic targets in the development of anthrax treatment and prophylactic approaches complementing anti-lethal toxin therapy.

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Article
Absence of association between angiotensin converting enzyme polymorphism and development of adult respiratory distress syndrome in patients with severe acute respiratory syndrome: a case control study

Authors: Chan KC Allen --- Tang Nelson LS --- Hui David SC --- Chung Grace TY --- et al.
DOI: 10.1186/1471-2334-5-26
Pages: 26
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Abstract

Abstract

Background

It has been postulated that genetic predisposition may influence the susceptibility to SARS-coronavirus infection and disease outcomes. A recent study has suggested that the deletion allele (D allele) of the angiotensin converting enzyme (ACE) gene is associated with hypoxemia in SARS patients. Moreover, the ACE D allele has been shown to be more prevalent in patients suffering from adult respiratory distress syndrome (ARDS) in a previous study. Thus, we have investigated the association between ACE insertion/deletion (I/D) polymorphism and the progression to ARDS or requirement of intensive care in SARS patients.

Method

One hundred and forty genetically unrelated Chinese SARS patients and 326 healthy volunteers were recruited. The ACE I/D genotypes were determined by polymerase chain reaction and agarose gel electrophoresis.

Results

There is no significant difference in the genotypic distributions and the allelic frequencies of the ACE I/D polymorphism between the SARS patients and the healthy control subjects. Moreover, there is also no evidence that ACE I/D polymorphism is associated with the progression to ARDS or the requirement of intensive care in the SARS patients. In multivariate logistic analysis, age is the only factor associated with the development of ARDS while age and male sex are independent factors associated with the requirement of intensive care.

Conclusion

The ACE I/D polymorphism is not directly related to increased susceptibility to SARS-coronavirus infection and is not associated with poor outcomes after SARS-coronavirus infection.

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Article
High versus standard doses interferon-alpha in the treatment of naïve chronic hepatitis C patients in Taiwan: a 10-year cohort study

Authors: Yu Ming-Lung --- Dai Chia-Yen --- Chen Shinn-Cherng --- Lee Li-Po --- et al.
DOI: 10.1186/1471-2334-5-27
Pages: 27
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Abstract

Abstract

Background

Interferon-alpha monotherapy is effective in less than one-third patients with chronic hepatitis C. The dose-effect, tolerability and durability of interferon-alpha treatment and its long-term effect on the prevention of cirrhosis and hepatocellular carcinoma in naïve Taiwanese patients with chronic hepatitis C have not been well investigated. We conducted the present cohort study treated with high and standard interferon-alpha to illustrate the issues.

Methods

We performed a long-term virologic and histological follow-up of 214 chronic hepatitis C patients treated with interferon-alpha, 3 million units (3-MU, n = 80) or 6-MU (n = 134) thrice weekly for 24 weeks, in Taiwan between 1992 and 2001.

Results

There was no difference in the incidence of discontinuation between 3-MU and 6-MU groups (4/80, 5.0% versus 10/134. 7.5%). The 6-MU group had similar incidence of adverse events with the 3-MU group, except that 6-MU group had significantly higher incidence of psychological manifestations, mainly presented as irritability. The rates of sustained virological response (SVR) were significantly higher in 6-MU regimen (37.1%) than in 3-MU regimen (23.7%, p < 0.05) in per protocol analysis. Based on multivariate analysis, baseline viral load was strongly associated with SVR, followed by hepatitis C virus genotype, interferon-alpha regimen, and liver fibrosis. A histological improvement in necroinflammatory activity, but not in fibrosis was observed in the follow-up biopsy performed 0.5–5.5 years (mean: 1.9 years, n = 51) after end-of-treatment. Among patients without SVR, there was more activity improvement in 6-MU group. The durability of SVR was 100% (18/18) and 97.8% (45/46) for 3-MU and 6-MU group, respectively, in a mean follow-up period of 6.81 years (5.25–9.18 years). For 163 baseline non-cirrhotic patients, 9 of 84 (10.7%) non-responders and 3 of 79 (3.8%) sustained responders progressed to cirrhosis during a mean follow-up period of 5.52 and 5.74 years, respectively (p = 0.067, Kaplan-Meier survival analysis, log-rank test). For all 200 patients, hepatocellular carcinoma was detected in 12 of 113 (10.6%) non-responders and one of 87 (1.1%) sustained responders during a mean follow-up period of 5.67 and 5.73 years, respectively (p < 0.01, Kaplan-Meier survival analysis, log-rank test).

Conclusion

We confirm the dose effect of interferon-alpha in chronic hepatitis C. Six-MU regimen had better efficacy than 3-MU regimen in virologic and histological responses. Both regimens had good tolerability and durability in Taiwan. Sustained response could reduce the incidence of cirrhotic change and hepatocarcinogenesis.

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Article
Difficulties in assessing cytomegalovirus-associated gastric perforation in an HIV-infected patient

Authors: Mégarbane Bruno --- Résière Dabor --- Ferrand Jacqueline --- Raskine Laurent --- et al.
DOI: 10.1186/1471-2334-5-28
Pages: 28
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Abstract

Abstract

Background

Active Cytomegalovirus (CMV) infection is a common complication in advanced symptomatic Human Immunodeficiency Virus (HIV) infection. CMV-induced intestinal perforations are hard to diagnose and may be observed throughout the gastrointestinal tract. Isolated stomach perforation is exceptional.

Case presentation

A 47-year-old man was admitted to our intensive care unit with multiorgan failure. Gastrointestinal endoscopic examination showed erythematous gastritis but normal duodenum and colon. CMV blood culture was positive. Histologic examination of a gastric biopsy showed inflammatory infiltrate and immunostaining typical intranuclear CMV inclusion bodies. Concomitant abdominal CT scan disclosed large peripancreatic hypodensities without pneumoperitoneum. The patient died despite supportive therapies and ganciclovir infusion. Postmortem examination showed a 4-cm gastric perforation adhering to the transverse colon and liver, with a thick necrotic inflammatory coating around the pancreas. The whole GI tract, except the stomach, was normal. As other causes, especially Helicobacter pylori infection could be ruled out, a causal relationship between CMV and gastric disease was assumed.

Conclusion

CMV may be responsible for gastric perforations, with difficulties in assessing the diagnosis. Early diagnosis based on cautious endoscopy and histopathologic examination is needed to make a favorable outcome possible.

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Article
Tuberculous dilated cardiomyopathy: an under-recognized entity?

Authors: Agarwal Ritesh --- Malhotra Puneet --- Awasthi Anshu --- Kakkar Nandita --- et al.
DOI: 10.1186/1471-2334-5-29
Pages: 29
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Abstract

Abstract

Background

Tuberculosis (TB) is a common public health problem in many parts of the world. TB is generally believed to spare these four organs-heart, skeletal muscle, thyroid and pancreas. We describe a rare case of myocardial TB diagnosed on a post-mortem cardiac biopsy.

Case presentation

Patient presented with history suggestive of congestive heart failure. We describe the clinical presentation, investigations and outcome of this case, and review the literature on the involvement of myocardium by TB.

Conclusion

Involvement of myocardium by TB is rare. However it should be suspected as a cause of congestive heart failure in any patient with features suggestive of TB. Increasing recognition of the entity and the use of endomyocardial biopsy may help us detect more cases of this "curable" form of cardiomyopathy.

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Article
Paradise – not without its plagues: Overwhelming Blastomycosis pneumonia after visit to lakeside cottages in Northeastern Ontario

Authors: Parmar Malvinder S
DOI: 10.1186/1471-2334-5-30
Pages: 30
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Abstract

Abstract

Background

Visiting lakes and cottages is a common leisure activity during summer among most Canadians and paradise for some. Various leisure activities are involved during these visits, including cleaning and 'airing' the cottage after long-winters, activities at the lakes and dock building etc, exposing the Canadians to moist soil and decaying woods – a source of white or tan mould – Blastomyces dermatitidis that may cause a flu-like illness to severe pneumonia that often remains a diagnostic challenge and results in delay in diagnosis and appropriate treatment thereby increasing associated morbidity and mortality.

Case Presentations

Five cases of overwhelming acute blastomycosis pneumonia are presented. Four of the five patients presented within few weeks of their visit to the cottages and surrounding lakes and all were initially treated as "community acquired pneumonia" that resulted in delay in diagnosis and poor outcome in the first patient. The first case, however, taught an important lesson that led to high-index of suspicion in the others with early diagnosis and improved outcomes. Interestingly, all patients were obese and had a shorter incubation period and severe clinical course. The possible mechanism for early and severe disease in association with obesity is speculated and literature is reviewed.

Conclusion

High-index of suspicion is important in the early diagnosis and appropriate management acute blastomycosis pneumonia to improve associated morbidity and mortality.

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Article
Investigation of Staphylococcus strains with heterogeneous resistance to glycopeptides in a Turkish university hospital

Authors: Nakipoglu Yasar --- Derbentli Sengul --- Cagatay Atahan A --- Katranci Handan
DOI: 10.1186/1471-2334-5-31
Pages: 31
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Abstract

Abstract

Background

The hetero-glycopeptide intermediate staphylococci is considered to be the precursor of glycopeptide intermediate staphylococci especially vancomycin intermediate Staphylococcus aureus (VISA). For this purpose, we aimed to investigate the heterogeneous resistance to glycopeptide and their frequencies in 135 Staphylococcus strains.

Methods

Heterogeneous resistance of Staphylococcus strains was detected by inoculating the strains onto Brain Heart Infusion agar supplemented with 4 mg/L of vancomycin (BHA-V4). Agar dilution method was used for determining MICs of glycopeptides and population analysis profile was performed for detecting frequency of heterogeneous resistance for the parents of selected strains on BHA-4.

Results

Eight (6%) out of 135 Staphylococcus strains were exhibited heterogeneous resistance to at least one glycopeptide. One (1.2%) out of 81 S. aureus was found intermediate resistance to teicoplanin (MIC 16 mg/L). Other seven strains were Staphylococcus haemolyticus (13%) out of 54 coagulase negative staphylococci (CoNS). Six of the seven strains were detected heterogeneously reducing susceptibility to vancomycin (MICs ranged between 5–8 mg/L) and teicoplanin (MICs ranged between 32–64 mg/L), and one S. haemolyticus was found heterogeneous resistance to teicoplanin (MIC 32 mg/L). Frequencies of heterogeneous resistance were measured being one in 106 – 107 cfu/ml. MICs of vancomycin and teicoplanin for hetero-staphylococci were determined as 2–6 folds and 3–16 folds higher than their parents, respectively. These strains were isolated from six patients (7%) and two (4%) of health care wokers hands. Hetero-VISA strain was not detected.

Conclusion

Heterogeneous resistance to glycopeptide in CoNS strains was observed to be significantly more emergent than those of S. aureus strains (vancomycin P 0.001, teicoplanin, P 0.007). The increase MICs of glycopeptide resistance for subpopulations of staphylococci comparing with their parents could be an important clue for recognizing the early steps in the appearance of VISA strains. We suggested to screen clinical S. aureus and CoNS strains, systematically, for the presence of heterogeneously resistance to glycopeptide.

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Article
Prevalence of oropharyngeal beta-lactamase-producing Capnocytophaga spp. in pediatric oncology patients over a ten-year period

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Abstract

Abstract

Background

The aim of this study was to evaluate the prevalence of beta-lactamase-producing Capnocytophaga isolates in young children hospitalized in the Pediatric Oncology Department of Hôpital Sud (Rennes, France) over a ten-year period (1993–2002).

Methods

In neutropenic children, a periodic survey of the oral cavity allows a predictive evaluation of the risk of systemic infections by Capnocytophaga spp. In 449 children with cancer, 3,053 samples were collected by oral swabbing and plated on TBBP agar. The susceptibility of Capnocytophaga isolates to five beta-lactams was determined.

Results

A total of 440 strains of Capnocytophaga spp. were isolated, 309 (70%) of which were beta-lactamase producers. The beta-lactamase-producing strains were all resistant to cefazolin, 86% to amoxicillin, and 63% to ceftazidime. The proportion of strains resistant to third-generation cephalosporins remained high throughout the ten-year study, while susceptibility to imipenem and amoxicillin combined with clavulanic acid was always conserved.

Conclusion

These results highlight the risk of antibiotic failure in Capnocytophaga infections and the importance of monitoring immunosuppressed patients and testing for antibiotic susceptibility and beta-lactamase production.

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Article
Prevalence and risk factors of syphilis infection among drug addicts

Authors: Scherbaum Norbert --- Baune Bernhard T --- Mikolajczyk Rafael --- Kuhlmann Thomas --- et al.
DOI: 10.1186/1471-2334-5-33
Pages: 33
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Abstract

Abstract

Background

Recent epidemiological data show an increased trend of official estimates for syphilis infection in the general population. Many of the infected cases remain undetected leaving an underestimation of the true prevalence of syphilis in the general population, but also among subpopulations such as illicit drug users. There is limited epidemiological data published on the proportion and risk factors of syphilis infections associated with illicit drug abuse.

Methods

Illicit drug addicts (n = 1223) in inpatients units in Germany were screened (2000–01) for syphilis and interviewed regarding patterns of drug use and sexual behaviour. TPHA-test for initial screening and FTA-ABS-IgM test in TPHA-positive patients were used.

Results

In total, TPHA-tests were positive in 39 (3.3%) and 7 patients (0.6%) were IgM positive. The prevalence rate for syphilis in males was 1.9% and for women it was 8.5%. Female patients were 4.56 (CI 95% 2.37–8.78) times more likely to have a positive TPHA test than males. Sexual behaviours such as high number of sexual partners, sex for drugs/money, sex on the first day were associated with syphilis infection only in women. Females with frequent sex for drugs or money had 4.31 (CI 95% 2.32–8.52) times more likely a reactive TPHA test than remaining patients. Neither the sociodemographic factors nor sexual behaviour were statistically significant associated with syphilis infection among men at all.

Conclusion

Our data suggest the need for screening for syphilis among these illicit drug users in inpatient settings, in particular among sexual active women. This conclusion is corroborated by the finding of increasing numbers of syphilis infections in the general population. The identification of syphilis cases among drug addicts would give treatment options to these individuals and would help to reduce the spread of infection in this population, but also a spread into heterosexual populations related to prostitution.

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Article
Echinococcal disease in Alberta, Canada: more than a calcified opacity

Authors: Somily Ali --- Robinson Joan L --- Miedzinski Lilly J --- Bhargava Ravi --- et al.
DOI: 10.1186/1471-2334-5-34
Pages: 34
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Abstract

Abstract

Background

Most cases of echinococcal disease (ED) acquired in Canada are thought to be due to the sylvatic form of Echinococcus granulosus, which may be more benign than ED due to either Echinococcus multilocularis or the pastoral form of E. granulosus. There are limited descriptions of the clinical course and outcome of Canadian patients with ED in the modern era.

Methods

A retrospective chart review was performed of patients hospitalized with echinococcal disease (ED) from 1991 to 2001 in Edmonton, Alberta.

Results

Forty-two cases of ED were identified of which 19 were definite, 3 probable, and 20 possible. Further analysis was limited to the 22 definite and probable cases, of which 77% were female and 41% aboriginal, with an age range of 5 to 87 years. Nine patients (40%) had pulmonary involvement and 11 (50%) hepatic involvement. One patient had an intracardiac mass presenting as a cerebrovascular event and one had a splenic cyst. Seven of the 22 patients had combined surgical resection and medical treatment, six had surgical resection of the cyst alone, four had cyst aspiration, one had medical treatment alone and four had no specific treatment. There was no mortality attributable to ED but three patients died of unrelated illnesses.

Conclusion

Echinococcal disease in northern Alberta has a marked diversity of clinical presentations, and generally has a good prognosis despite a wide variety of therapeutic interventions.

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Article
Blood cultures in ambulatory outpatients

Authors: Laupland Kevin B --- Church Deirdre L --- Gregson Daniel B
DOI: 10.1186/1471-2334-5-35
Pages: 35
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Abstract

Abstract

Background

Blood cultures are a gold standard specific test for diagnosing many infections. However, the low yield may limit their usefulness, particularly in low-risk populations. This study was conducted to assess the utility of blood cultures drawn from ambulatory outpatients.

Methods

Blood cultures drawn at community-based collection sites in the Calgary Health Region (population 1 million) in 2001 and 2002 were included in this study. These patients were analyzed by linkages to acute care health care databases for utilization of acute care facilities within 2 weeks of blood culture draw.

Results

3102 sets of cultures were drawn from 1732 ambulatory outpatients (annual rate = 89.4 per 100,000 population). Significant isolates were identified from 73 (2.4%) sets of cultures from 51 patients, including Escherichia coli in 18 (35%) and seven (14%) each of Staphylococcus aureus and Streptococcus pneumoniae. Compared to patients with negative cultures, those with positive cultures were older (mean 49.6 vs. 40.1 years, p < 0.01), and more likely to subsequently receive care at a regional emergency department, outpatient antibiotic clinic, or hospital (35/51 vs. 296/1681, p < 0.0001). Of the 331 (19%) patients who received acute care treatment, those with positive cultures presented sooner after community culture draw (median 2 vs. 3 days, p < 0.01) and had longer median treatment duration (6 vs. 2 days, p < 0.01).

Conclusion

Blood cultures drawn in outpatient settings are uncommonly positive, but may define patients for increased intensity of therapy. Strategies to reduce utilization without excluding patients with positive cultures need to be developed for this patient population.

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Article
Hepatitis E virus infection in hemodialysis patients: A seroepidemiological survey in Iran

Authors: Taremi Mahnaz --- Khoshbaten Manouchehr --- Gachkar Latif --- EhsaniArdakani MohammadJavad --- et al.
DOI: 10.1186/1471-2334-5-36
Pages: 36
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Abstract

Abstract

Background

The hepatitis E virus (HEV) has a global distribution and is known to have caused large waterborne epidemics of icteric hepatitis. Transmission is generally via the fecal-oral route. Some reports have suggested parenteral transmission of HEV. Anti-HEV prevalence data among chronic hemodialysis (HD) patients are few and give conflicting results.

Methods

This cross-sectional study was conducted in August of 2004. We tested 324 chronic HD patients attending three different units in the city of Tabriz, northwestern part of Iran, for anti-HEV antibody. A specific solid- phase enzyme-linked immunoassay (Diapro, Italy) was used.

Results

The overall seroprevalence of hepatitis E was 7.4 %(95% CI: 4.6%–10.6%). The prevalence rate of HBV and HCV infection were 4.6% (95% CI: 2.3%–6.9%) and 20.4% (95% CI: 16%–24.8%), respectively. No significant association was found between anti-HEV positivity and age, sex, duration of hemodialysis, positivity for hepatitis B or C virus infection markers and history of transfusion.

Conclusion

We observed high anti-HEV antibody prevalence; there was no association between HEV and blood borne infections (HBV, HCV, and HIV) in our HD patients. This is the first report concerning seroepidemiology of HEV infection in a large group of chronic HD individuals in Iran.

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Article
Clinical outcomes in typhoid fever: adverse impact of infection with nalidixic acid-resistant Salmonella typhi

Authors: Kadhiravan Tamilarasu --- Wig Naveet --- Kapil Arti --- Kabra SK --- et al.
DOI: 10.1186/1471-2334-5-37
Pages: 37
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Abstract

Abstract

Background

Widespread use of fluoroquinolones has resulted in emergence of Salmonella typhi strains with decreased susceptibility to fluoroquinolones. These strains are identifiable by their nalidixic acid-resistance. We studied the impact of infection with nalidixic acid-resistant S. typhi (NARST) on clinical outcomes in patients with bacteriologically-confirmed typhoid fever.

Methods

Clinical and laboratory features, fever clearance time and complications were prospectively studied in patients with blood culture-proven typhoid fever, treated at a tertiary care hospital in north India, during the period from November 2001 to October 2003. Susceptibility to amoxycillin, co-trimoxazole, chloramphenicol, ciprofloxacin and ceftriaxone were tested by disc diffusion method. Minimum inhibitory concentrations (MIC) of ciprofloxacin and ceftriaxone were determined by E-test method.

Results

During a two-year period, 60 patients (age [mean ± SD]: 15 ± 9 years; males: 40 [67%]) were studied. All isolates were sensitive to ciprofloxacin and ceftriaxone by disc diffusion and MIC breakpoints. However, 11 patients had clinical failure of fluoroquinolone therapy. Infections with NARST isolates (47 [78%]) were significantly associated with longer duration of fever at presentation (median [IQR] 10 [7-15] vs. 4 [3-6] days; P = 0.000), higher frequency of hepatomegaly (57% vs. 15%; P = 0.021), higher levels of aspartate aminotransferase (121 [66–235] vs. 73 [44–119] IU/L; P = 0.033), and increased MIC of ciprofloxacin (0.37 ± 0.21 vs. 0.17 ± 0.14 μg/mL; P = 0.005), as compared to infections with nalidixic acid-susceptible isolates. All 11 patients with complications were infected with NARST isolates. Total duration of illness was significantly longer in patients who developed complications than in patients who did not (22 [14.8–32] vs. 12 [9.3–20.3] days; P = 0.011). Duration of prior antibiotic intake had a strong positive correlation with the duration of fever at presentation (r = 0.61; P = 0.000) as well as the total duration of illness (r = 0.53; P = 0.000).

Conclusion

Typhoid fever caused by NARST infection is associated with poor clinical outcomes, probably due to delay in initiating appropriate antibiotic therapy. Fluoroquinolone breakpoints for S. typhi need to be redefined and fluoroquinolones should no longer be used as first-line therapy, if the prevalence of NARST is high.

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Article
Fatal meningitis in a previously healthy young adult caused by Streptococcus pneumoniae serotype 38: an emerging serotype?

Authors: Baker Carolyn I --- Barrozo Christopher P --- Ryan Margaret AK --- Pearse Lisa A --- et al.
DOI: 10.1186/1471-2334-5-38
Pages: 38
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Abstract

Abstract

Background

In December 2001, a fatal case of pneumococcal meningitis in a Marine Corps recruit was identified. As pneumococcal vaccine usage in recruit populations is being considered, an investigation was initiated into the causative serotype.

Case presentation

Traditional and molecular methods were utilized to determine the serotype of the infecting pneumococcus. The pneumococcal isolate was identified as serotype 38 (PS38), a serotype not covered by current vaccine formulations. The global significance of this serotype was explored in the medical literature, and found to be a rare but recognized cause of carriage and invasive disease.

Conclusion

The potential of PS38 to cause severe disease is documented in this report. Current literature does not support the hypothesis that this serotype is increasing in incidence. However, as we monitor the changing epidemiology of pneumococcal illness in the US in this conjugate era, PS38 might find a more prominent and concerning niche as a replacement serotype.

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Article
A sensitive flow cytometric methodology for studying the binding of L. chagasi to canine peritoneal macrophages

Authors: Gonçalves Ricardo --- Vieira Etel R --- Melo Maria N --- Gollob Kenneth J --- et al.
DOI: 10.1186/1471-2334-5-39
Pages: 39
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Abstract

Abstract

Background

The Leishmania promastigote-macrophage interaction occurs through the association of multiple receptors on the biological membrane surfaces. The success of the parasite infection is dramatically dependent on this early interaction in the vertebrate host, which permits or not the development of the disease. In this study we propose a novel methodology using flow cytometry to study this interaction, and compare it with a previously described "in vitro" binding assay.

Methods

To study parasite-macrophage interaction, peritoneal macrophages were obtained from 4 dogs and adjusted to 3 × 106 cells/mL. Leishmania (Leishmania) chagasi parasites (stationary-phase) were adjusted to 5 × 107 cells/mL. The interaction between CFSE-stained Leishmania chagasi and canine peritoneal macrophages was performed in polypropylene tubes to avoid macrophage adhesion. We carried out assays in the presence or absence of normal serum or in the presence of a final concentration of 5% of C5 deficient (serum from AKR/J mice) mouse serum. Then, the number of infected macrophages was counted in an optical microscope, as well as by flow citometry. Macrophages obtained were stained with anti-CR3 (CD11b/CD18) antibodies and analyzed by flow citometry.

Results

Our results have shown that the interaction between Leishmania and macrophages can be measured by flow cytometry using the fluorescent dye CFSE to identify the Leishmania, and measuring simultaneously the expression of an important integrin involved in this interaction: the CD11b/CD18 (CR3 or Mac-1) β2 integrin.

Conclusion

Flow cytometry offers rapid, reliable and sensitive measurements of single cell interactions with Leishmania in unstained or phenotypically defined cell populations following staining with one or more fluorochromes.

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Article
Clinical presentation of pertussis in fully immunized children in Lithuania

Authors: Narkeviciute Irena --- Kavaliunaite Ema --- Bernatoniene Genovaite --- Eidukevicius Rimantas
DOI: 10.1186/1471-2334-5-40
Pages: 40
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Abstract

Abstract

Background

In Lithuania, the vaccination coverage against pertussis is high. Nevertheless, there is a significant increase in pertussis cases in fully immunized children. The aim of our study was to determine the frequency of classical symptoms of laboratory confirmed pertussis and describe its epidemiology in children fully vaccinated against pertussis.

Methods

From May to December 2001, 70 children aged 1 month to 15 years, suffering from prolonged cough were investigated in the Centre of Paediatrics, Vilnius University Children's Hospital. The collected information included personal data, vaccination history, clinical symptoms of the current illness, and treatment before hospitalization. At the admission to the hospital blood samples were taken from all studied children for Bordetella pertussis IgM and IgA.

Results

A total of 53 (75.7%) of the 70 recruited patients with prolonged cough showed laboratory evidence of pertussis. 32 of them were fully vaccinated with whole cell pertussis vaccine (DTP). The age of fully vaccinated patients varied from 4 to 15 years (average 10.9 ± 3.1; median 11). The time period between the last vaccination dose (fourth) and the clinical manifestation of pertussis was 2.6–13 years (average 8.9 ± 3.0; median 9). More than half of the children before the beginning of pertussis were in contact with persons suffering from long lasting cough illness in the family, school or day-care center. The mean duration from onset of pertussis symptoms until hospitalization was 61.4 ± 68.3 days (range, 7 to 270 days; median 30). For 11 patients who had had two episodes (waves) of coughing, the median duration of cough was 90 days, and for 21 with one episode 30 days (p < 0.0002). Most of the children (84.4%) had paroxysmal cough, 31.3% had post-tussive vomiting, 28.1% typical whoop, and 3.1% apnea. Only 15.6% children had atypical symptoms of pertussis.

Conclusion

Fully vaccinated children fell ill with pertussis at the median of 11 years old, 9 years following pertussis vaccination. More than half of the children could catch pertussis at home, at school or day-care center. Clinical picture of pertussis in previously immunized children is usually characterized by such classical symptoms as prolonged and paroxysmal cough, rarely by whopping and post-tussive vomiting, and very rarely by apnea.

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Article
Salivary antibodies induced by the seven-valent PncOMPC conjugate vaccine in the Finnish Otitis Media Vaccine Trial

Authors: Nurkka Anu --- Lahdenkari Mika --- Palmu Arto AI --- Käyhty Helena
DOI: 10.1186/1471-2334-5-41
Pages: 41
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Abstract

Abstract

Background

Mucosal antibodies have been suggested to have a role in defence against pneumococcal infections. We investigated here the ability of a seven-valent pneumococcal conjugate vaccine, PncOMPC, to induce mucosal immune response.

Methods

Healthy Finnish children (n = 111), a subcohort of the Finnish Otitis Media Vaccine Trial, were recruited and 56 of them were immunised with the PncOMPC at the age of 2, 4, and 6 months. At 12 months of age, 49 of them received the PncOMPC and 7 were vaccinated with the pneumococcal polysaccharide vaccine (PncPS) as a booster. The control group of 55 children received a hepatitis B vaccine at the same ages. Salivary anti-Pnc IgG, IgA, IgA1, and IgA2 antibodies to serotypes 6B, 14, 19F, and 23F were measured in both groups at the age of 7 and 13 months.

Results

Salivary anti-Pnc IgG and IgA were detected more often in the PncOMPC than in the control group. However, the difference between groups was significant only for 19F and 23F IgA concentrations at the age of 7 months. At the age of 13 months, antibody concentrations did not differ between PncOMPC and control groups. The rises in IgA concentrations between 7 and 13 months of age were mainly of subclass IgA1. Further, there is a clear trend that PncPS booster induces higher salivary anti-Pnc PS antibody concentrations than the PncOMPC.

Conclusion

We found that PncOMPC can induce a mucosal IgA response. However, the actual impact of mucosal antibodies in protection against pneumococcal infections is not clear.

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Article
Embolic stroke complicating Staphylococcus aureus endocarditis circumstantially linked to rectal trauma from foreign body: a first case report

Authors: Pandey Braj B --- Dang Tuan C --- Healy John F
DOI: 10.1186/1471-2334-5-42
Pages: 42
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Abstract

Abstract

Background

Diagnostic and therapeutic instrumentation of the lower gastrointestinal tract has been reported to result in bacteremia and endocarditis. No such case has been reported in persons with a history of rectal foreign body insertion despite its potential for greater trauma.

Case presentation

A 58-year-old male was admitted with confusion and inability to speak. His past history was notable for hospitalization to extract a retained plastic soda bottle from the rectosigmoid two years prior. On examination, he was febrile, tachycardic and hypotensive. There was an apical pansystolic murmur on cardiac examination. He had a mixed receptive and expressive aphasia, and a right hemiparesis. On rectal examination he had perianal erythema and diminished sphincter tone. Magnetic resonance imaging of the brain showed infarction of the occipital and frontal lobes. Transesophageal Echocardiography of the heart revealed vegetations on the mitral valve. All of his blood culture bottles grew methicillin sensitive Staphylococcus aureus. He was successfully treated for bacterial endocarditis with intravenous nafcillin and gentamicin. The rectum is frequently colonized by Staphylococcus aureus and trauma to its mucosa can lead to bacteremia and endocarditis with this organism.

In the absence of corroborative evidence such as presented here, it is difficult to make a correlation between staphylococcal endocarditis and anorectal foreign body insertion due to patients being less than forthcoming

Conclusion

There is a potential risk of staphylococcal bacteremia and endocarditis with rectal foreign body insertion. Further studies are needed to explore this finding. Detailed sexual history and patient counseling should be made a part of routine primary care.

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Article
Efficacy and safety of telithromycin 800 mg once daily for 7 days in community-acquired pneumonia: an open-label, multicenter study

Authors: Fogarty Charles M --- Patel Tushar C --- Dunbar Lala M --- Leroy Bruno P
DOI: 10.1186/1471-2334-5-43
Pages: 43
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Abstract

Abstract

Background

Community-acquired pneumonia (CAP) remains a major cause of morbidity and mortality throughout the world. Telithromycin (a new ketolide) has shown good in vitro activity against the key causative pathogens of CAP, including S pneumoniae resistant to penicillin and/or macrolides.

Methods

The efficacy and safety of telithromycin 800 mg orally once daily for 7 days in the treatment of CAP were assessed in an open-label, multicenter study of 442 adults.

Results

Of 149 microbiologically evaluable patients, 57 (9 bacteremic) had Streptococcus pneumoniae. Of the 57 S pneumoniae pathogens isolated in these patients, 9 (2 bacteremic) were penicillin- or erythromycin-resistant; all 57 were susceptible to telithromycin and were eradicated. Other pathogens and their eradication rates were: Haemophilus influenzae (96%), Moraxella catarrhalis (100%), Staphylococcus aureus (80%), and Legionella spp. (100%). The overall bacteriologic eradication rate was 91.9%. Of the 357 clinically evaluable patients, clinical cure was achieved in 332 (93%). In the 430 patients evaluable for safety, the most common drug-related adverse events were diarrhea (8.1%) and nausea (5.8%).

Conclusion

Telithromycin 800 mg once daily for 7 days is an effective and well-tolerated oral monotherapy and offers a new treatment option for CAP patients, including those with resistant S pneumoniae.

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Article
Congenital rubella syndrome in Iran

Authors: Sadighi Jila --- Eftekhar Hasan --- Mohammad Kazem
DOI: 10.1186/1471-2334-5-44
Pages: 44
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Abstract

Abstract

Background

Congenital rubella syndrome (CRS) can be prevented with appropriate vaccination programs. The prevalence rates of rubella and CRS in Iran are unknown; therefore, the risk of exposure in pregnant women is not clear. The prevalence of CRS in the pre-vaccine period can be estimated by evaluating the proportion of children in the population with sensorineural hearing loss attributable to rubella.

Methods

This was a case-control study to estimate prevalence of CRS in Tehran (Iran) by evaluating the proportion of children with sensorineural hearing loss attributable to rubella. The study used rubella antibody titer as an indicator, and compared the prevalence of rubella antibody between children with and without sensorineural hearing loss. Using these findings, the proportion of cases of sensorineural hearing loss attributable to rubella was estimated.

Results

A total of 225 children aged 1 to 4 years were entered into the study (113 cases and 112 controls). There was a significant difference between cases and controls with regard to rubella antibody seropositivity (19.5% vs. 8.9%, respectively, odds ratio = 2.47, 95% CI = 1.04–5.97). The proportion of sensorineural hearing loss cases attributable to rubella was found to be 12%, corresponding to a CRS prevalence of 0.2/1000.

Conclusion

The prevalence of CRS was approximately 0.2/1000 before rubella vaccination in Iran, Moreover; the results suggest that implementation of appropriate rubella vaccination programs could potentially prevent about 12% of cases of sensorineural hearing loss in Iranian children. This data could potentially be used as baseline data, which in conjunction with an appropriate method, to establish a surveillance system for rubella vaccination in Iran. An appropriate surveillance system is needed, because the introduction of a rubella vaccine without epidemiological data and an adequate monitoring program could result in the shifting of rubella cases to higher ages, and increasing the incidence of CRS.

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Article
The therapeutic effect of the neuropeptide hormone somatostatin on Schistosoma mansoni caused liver fibrosis

Authors: Chatterjee Shyama --- Vrolix Gunther --- Depoortere Inge --- Peeters Theo --- et al.
DOI: 10.1186/1471-2334-5-45
Pages: 45
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Abstract

Abstract

Background

The neuropeptide somatostatin is one of the major regulatory peptides in the central nervous system and the digestive tract. Our recent work has delineated an association between fibrosis and low levels of endogenous somatostatin plasma levels in Schistosoma mansoni infected subjects. Based on these results this paper explores the therapeutic potential of somatostatin in a mouse model of hepatic fibrosis associated with S. mansoni infections.

Methods

Groups of outbred Swiss mice were infected with 100 S. mansoni cercariae, infection maintained till weeks 10 or 14, and then somatostatin therapy delivered in two regimens – Either a one or a two-day treatment. All animals were sacrificed one week after therapy and controlled for liver, spleen and total body weight. Circulating somatostatin levels in mice plasma were measured at the time of sacrifice by means of a radio-immuno assay. GraphPad Prism® was used for statistical calculations.

Results

Somatostatin administration showed little toxicity, probably due to its short half-life. Total liver and spleen weights of S. mansoni infected animals increased over time, with no changes observed due to somatostatin therapy. Total body weights were decreased after infection but were not affected by somatostatin therapy. Snap frozen liver sections were stained with haematoxylin-eosin or Masson's trichrome to study parasite count, hepatocyte status, granuloma size and cellularity. After somatostatin treatment mean egg counts per liver section (43.76 ± 3.56) were significantly reduced as compared to the egg counts in untreated mice after 10 weeks of infection (56.01 ± 3.34) (P = 0.03). Similar significant reduction in parasite egg counts were also observed after somatostatin treatment at 14 weeks of infection (56.62 ± 3.02) as compared to untreated animals (69.82 ± 2.77)(P = 0.006). Fibrosis was assessed from the spectrophotometric determination of tissue hydroxyproline. Infection with S. mansoni caused increased hydroxyproline levels (9.37 ± 0.63 μmol at wk10; 9.65 ± 0.96 μmol at wk14) as compared to uninfected animals (1.06 ± 0.10 μmol). This significant increase in collagen content (P = 0.01; 0.007 respectively) marks the fibrosis observed at these time points. Treatment with somatostatin resulted in a significant decrease in hydroxyproline levels both at wk10 (4.76 ± 0.58 μmol) and at wk14 (5.8 ± 1.13 μmol) (P = 0.01; 0.03 respectively). Endogenous somatostatin levels were increased at wk10 (297 ± 37.24 pg/ml) and wk14 (206 ± 13.30 pg/ml) of infection as compared to uninfected mice (119 ± 11.99 pg/ml) (P = 0.01; 0.008 respectively). Circulating somatostatin levels in infected animals were not significantly affected by somatostatin treatment. Hepatocyte status remained unaltered and granulomas were not remarkably changed in size or cellularity.

Conclusion

Our experiments reveal an antifibrotic effect of somatostatin in schistosomiasis. We have previously shown that the somatostatin receptors SSTR2 and SSTR3 are present on the parasite egg and worms. We therefore hypothesize that somatostatin reduces either the number of parasite eggs or the secretion of fibrosis inducing-mediators. Our data suggest somatostatin may have therapeutic potential in S. mansoni mediated liver pathology.

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Article
Evaluation of amplified rDNA restriction analysis (ARDRA) for the identification of Mycoplasma species

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Abstract

Abstract

Background

Mycoplasmas are present worldwide in a large number of animal hosts. Due to their small genome and parasitic lifestyle, Mycoplasma spp. require complex isolation media. Nevertheless, already over 100 different species have been identified and characterized and their number increases as more hosts are sampled. We studied the applicability of amplified rDNA restriction analysis (ARDRA) for the identification of all 116 acknowledged Mycoplasma species and subspecies.

Methods

Based upon available 16S rDNA sequences, we calculated and compared theoretical ARDRA profiles. To check the validity of these theoretically calculated profiles, we performed ARDRA on 60 strains of 27 different species and subspecies of the genus Mycoplasma.

Results

In silico digestion with the restriction endonuclease AluI (AG^CT) was found to be most discriminative and generated from 3 to 13 fragments depending on the Mycoplasma species. Although 73 Mycoplasma species could be differentiated using AluI, other species gave undistinguishable patterns. For these, an additional restriction digestion, typically with BfaI (C^TAG) or HpyF10VI (GCNNNNN^NNGC), was needed for a final identification. All in vitro obtained restriction profiles were in accordance with the calculated fragments based on only one 16S rDNA sequence, except for two isolates of M. columbinum and two isolates of the M. mycoides cluster, for which correct ARDRA profiles were only obtained if the sequences of both rrn operons were taken into account.

Conclusion

Theoretically, restriction digestion of the amplified rDNA was found to enable differentiation of all described Mycoplasma species and this could be confirmed by application of ARDRA on a total of 27 species and subspecies.

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Article
High frequency of Fredrickson's phenotypes IV and IIb in Brazilians infected by human immunodeficiency virus

Authors: Albuquerque Edilma MV --- de Faria Eliana C --- Oliveira Helena CF --- Magro Daniela O --- et al.
DOI: 10.1186/1471-2334-5-47
Pages: 47
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Abstract

Abstract

Background

Human immunodeficiency virus (HIV) infection is very prevalent in Brazil. HIV therapy has been recently associated with coronary heart disease (CHD). Dyslipidemia is a major risk factor for CHD that is frequently described in HIV positive patients, but very few studies have been conducted in Brazilian patients evaluating their lipid profiles.

Methods

In the present work, we evaluated the frequency and severity of dyslipidemia in 257 Brazilian HIV positive patients. Two hundred and thirty-eight (93%) were submitted to antiretroviral therapy (224 treated with protease inhibitors plus nucleoside reverse transcriptase inhibitors, 14 treated only with the latter, 12 naive and 7 had no records of treatment).

The average time on drug treatment with antiretroviral therapy was 20 months. None of the patients was under lipid lowering drugs. Cholesterol, triglyceride, phospholipid and free fatty acids were determined by enzymatic colorimetric methods. Lipoprotein profile was estimated by the Friedewald formula and Fredrickson's phenotyping was obtained by serum electrophoresis on agarose. Apolipoprotein B and AI and lipoprotein "a" were measured by nephelometry.

Results

The Fredrickson phenotypes were: type IIb (51%), IV (41%), IIa (7%). In addition one patient was type III and another type V. Thirty-three percent of all HIV+ patients presented serum cholesterol levels ≥ 200 mg/dL, 61% LDL-cholesterol ≥ 100 mg/dL, 65% HDL-cholesterol below 40 mg/dL, 46% triglycerides ≥ 150 mg/dL and 10% have all these parameters above the limits. Eighty-six percent of patients had cholesterol/HDL-cholesterol ratio ≥ 3.5, 22% increased lipoprotein "a", 79% increased free fatty acids and 9% increased phospholipids. The treatment with protease inhibitors plus nucleoside reverse transcriptase inhibitors increased the levels of cholesterol and triglycerides in these patients when compared with naïve patients. The HDL-cholesterol (p = 0.01) and apolipoprotein A1 (p = 0.02) levels were inversely correlated with the time of protease inhibitor therapy while total cholesterol levels had a trend to correlate with antiretroviral therapy (p = 0.09).

Conclusion

The highly varied and prevalent types of dyslipidemia found in Brazilian HIV positive patients on antiretroviral therapies indicate the urgent need for their early diagnosis, the identification of the risk factors for CHD and, when needed, the prompt intervention on their lifestyle and/or with drug treatment.

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Article
Insufficient neutralization in testing a chlorhexidine-containing ethanol-based hand rub can result in a false positive efficacy assessment

Authors: Kampf Günter --- Shaffer Marc --- Hunte Corrine
DOI: 10.1186/1471-2334-5-48
Pages: 48
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Abstract

Abstract

Background

Effective neutralization in testing hand hygiene preparations is considered to be a crucial element to ensure validity of the test results, especially with the difficulty to neutralize chlorhexidine gluconate. Aim of the study was to measure the effect of chemical neutralization under practical test conditions according to EN 1500.

Methods

We have investigated two ethanol-based hand rubs (product A, based on 61% ethanol and 1% chlorhexidine gluconate; product B, based on 85% ethanol). The efficacy of products (application of 3 ml for 30 s) was compared to 2-propanol 60% (v/v) (two 3 ml rubs of 30 s each) on hands artificially contaminated with Escherichia coli using a cross-over design with 15 volunteers. Pre-values were obtained by rubbing fingertips for 1 minute in liquid broth. Post-values were determined by sampling immediately after disinfection in liquid broth with and without neutralizers (0.5% lecithin, 4% polysorbate 20).

Results

The neutralizers were found to be effective and non-toxic. Without neutralization in the sampling fluid, the reference disinfection reduced the test bacteria by 3.7 log10, product B by 3.3 log10 and product A by 4.8 log10 (P = 0.001; ANOVA). With neutralization the reference disinfection reduced the test bacteria by 3.5 log10, product B by 3.3 log10 and product A by 2.7 log10 (P = 0.011; ANOVA). In comparison to the reference treatment Product B lead to a lower mean reduction than the reference disinfection but the difference was not significant (P > 0.1; Wilcoxon-Wilcox test). Without neutralizing agents in the sampling fluid, product A yielded a significantly higher reduction of test bacteria (4.8; P = 0.02) as compared to the situation with neutralizing agents (2.7; P = 0.033).

Conclusion

The crucial step of neutralization lies in the sampling fluid itself in order to stop any residual bacteriostatic or bactericidal activity immediately after the application of the preparation, especially with chlorhexidine gluconate-containing preparations. This is particularly important at short application times such as the 30 s.

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Article
Treatment failure in a typhoid patient infected with nalidixic acid resistant S. enterica serovar Typhi with reduced susceptibility to Ciprofloxacin: a case report from Cameroon

Authors: Nkemngu Njinkeng J --- Asonganyi Etienne DN --- Njunda Anna L
DOI: 10.1186/1471-2334-5-49
Pages: 49
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Abstract

Abstract

Background

Fluoroquinolones or third generation cephalosporins are the drugs of choice for the treatment of typhoid fever. Treatment failure with fluoroquinolones has been reported in Asia and Europe. We report a case of ciprofloxacin treatment failure in typhoid fever in Cameroon.

Case presentation

A 29-year-old female patient with suspected typhoid fever from Kumba, Cameroon, yielded growth of Salmonella enterica serovar Typhi in blood culture. The isolate was resistant to nalidixic acid but sensitive to ciprofloxacin by disc diffusion test. However, the patient did not respond to treatment with ciprofloxacin, although the isolate was apparently susceptible to ciprofloxacin.

Conclusion

Treatment failure with ciprofloxacin in our case indicates the presence of nalidixic acid resistant S. enterica serovar Typhi (NARST) with reduced susceptibility to ciprofloxacin in Cameroon (Central Africa).

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Article
Diagnostic and prognostic utility of an inexpensive rapid on site malaria diagnostic test (ParaHIT f) among ethnic tribal population in areas of high, low and no transmission in central India

Authors: Singh Neeru --- Mishra AK --- Shukla MM --- Chand SK --- et al.
DOI: 10.1186/1471-2334-5-50
Pages: 50
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Abstract

Abstract

Background

Malaria presents a diagnostic challenge in most tropical countries. Rapid detection of the malaria parasite and early treatment of infection still remain the most important goals of disease management. Therefore, performance characteristics of the new indigenous ParaHIT f test (Span diagnostic Ltd, Surat, India) was determined among ethnic tribal population in four districts of different transmission potential in central India to assess whether this rapid diagnostic test (RDT) could be widely applied as a diagnostic tool to control malaria. Beyond diagnosis, the logical utilization of RDTs is to monitor treatment outcome.

Methods

A finger prick blood sample was collected from each clinically suspected case of malaria to prepare blood smear and for testing with the RDT after taking informed consent. The blood smears were read by an experienced technician blinded to the RDT results and clinical status of the subjects. The figures for specificity, sensitivity, accuracy and predictive values were calculated using microscopy as gold standard.

Results

The prevalence of malaria infection estimated by RDT in parallel with microscopy provide evidence of the type of high, low or no transmission in the study area. Analysis revealed (pooled data of all four epidemiological settings) that overall sensitivity, specificity and accuracy of the RDT were >90% in areas of different endemicity. While, RDT is useful to confirm the diagnosis of new symptomatic cases of suspected P. falciparum infection, the persistence of parasite antigen leading to false positives even after clearance of asexual parasitaemia has limited its utility as a prognostic tool.

Conclusion

The study showed that the ParaHIT f test was easy to use, reliable and cheap. Thus this RDT is an appropriate test for the use in the field by paramedical staff when laboratory facilities are not available and thus likely to contribute greatly to an effective control of malaria in resource poor countries.

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Article
Immunomodulatory intervention in sepsis by multidrug-resistant Pseudomonas aeruginosa with thalidomide: an experimental study

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Abstract

Abstract

Background

Thalidomide is an inhibitor of tumour necrosis factor-alpha (TNFα) that has been proven effective for the treatment of experimental sepsis by Escherichia coli. It was tested whether it might behave as an effective immunomodulator in experimental sepsis by multidrug-resistant (MDR) Pseudomonas aeruginosa.

Methods

Sepsis was induced by the intraperitoneal injection of 1 × 108 cfu/kg inoculum of the test isolate in a total of 109 Wistar rats divided in three groups as follows: group A controls; group B administered seed oil 30 minutes before bacterial challenge; and group C administered 50 mg/kg of thalidomide diluted in seed oil 30 minutes before bacterial challenge. Blood was sampled for estimation of endotoxins (LPS), TNFα, interferon-gamma (IFNγ), nitric oxide (NO) and malondialdehyde (MDA). LPS was measured by the QCL-1000 LAL assay, TNFα and IFNγ by ELISA, NO by a colorimetric assay and MDA by the thiobarbiturate assay.

Results

Mean (± SE) survival of groups A, B and C were 18.60 ± 1.84, 12.60 ± 0.60 and 30.50 ± 6.62 hours (p of comparisons A to C equal to 0.043 and B to C equal to 0.002). Decreased TNFα and NO levels were found in sera of animals of group C compared to group A. Plasma levels of LPS, MDA and IFNγ did not differ between groups.

Conclusion

Intake of thalidomide considerably prolonged survival in experimental sepsis by MDR P.aeruginosa an effect probably attributed to decrease of serum TNFα.

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Article
Transmission dynamics of rabies virus in Thailand: Implications for disease control

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Abstract

Abstract

Background

In Thailand, rabies remains a neglected disease with authorities continuing to rely on human death statistics while ignoring the financial burden resulting from an enormous increase in post-exposure prophylaxis. Past attempts to conduct a mass dog vaccination and sterilization program have been limited to Bangkok city and have not been successful. We have used molecular epidemiology to define geographic localization of rabies virus phylogroups and their pattern of spread in Thailand.

Methods

We analyzed 239 nucleoprotein gene sequences from animal and human brain samples collected from all over Thailand between 1998 and 2002. We then reconstructed a phylogenetic tree correlating these data with geographical information.

Results

All sequences formed a monophyletic tree of 2 distinct phylogroups, TH1 and TH2. Three subgroups were identified in the TH1 subgroup and were distributed in the middle region of the country. Eight subgroups of TH2 viruses were identified widely distributed throughout the country overlapping the TH1 territory. There was a correlation between human-dependent transportation routes and the distribution of virus.

Conclusion

Inter-regional migration paths of the viruses might be correlated with translocation of dogs associated with humans. Interconnecting factors between human socioeconomic and population density might determine the transmission dynamics of virus in a rural-to-urban polarity. The presence of 2 or more rabies virus groups in a location might be indicative of a gene flow, reflecting a translocation of dogs within such region and adjacent areas. Different approaches may be required for rabies control based on the homo- or heterogeneity of the virus. Areas containing homogeneous virus populations should be targeted first. Control of dog movement associated with humans is essential.

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Article
Rapid and simultaneous detection of human hepatitis B virus and hepatitis C virus antibodies based on a protein chip assay using nano-gold immunological amplification and silver staining method

Authors: Duan Lianlian --- Wang Yefu --- Li Shawn --- Wan Zhixiang --- et al.
DOI: 10.1186/1471-2334-5-53
Pages: 53
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Abstract

Abstract

Background

Viral hepatitis due to hepatitis B virus and hepatitis C virus are major public health problems all over the world. Traditional detection methods including polymerase chain reaction (PCR)-based assays and enzyme-linked immunosorbent assays (ELISA) are expensive and time-consuming. In our assay, a protein chip assay using Nano-gold Immunological Amplification and Silver Staining (NIASS) method was applied to detect HBV and HCV antibodies rapidly and simultaneously.

Methods

Chemically modified glass slides were used as solid supports (named chip), on which several antigens, including HBsAg, HBeAg, HBcAg and HCVAg (a mixture of NS3, NS5 and core antigens) were immobilized respectively. Colloidal nano-gold labelled staphylococcal protein A (SPA) was used as an indicator and immunogold silver staining enhancement technique was applied to amplify the detection signals, producing black image on array spots, which were visible with naked eyes. To determine the detection limit of the protein chip assay, a set of model arrays in which human IgG was spotted were structured and the model arrays were incubated with different concentrations of anti-IgG. A total of 305 serum samples previously characterized with commercial ELISA were divided into 4 groups and tested in this assay.

Results

We prepared mono-dispersed, spherical nano-gold particles with an average diameter of 15 ± 2 nm. Colloidal nano-gold-SPA particles observed by TEM were well-distributed, maintaining uniform and stable. The optimum silver enhancement time ranged from 8 to 12 minutes. In our assay, the protein chips could detect serum antibodies against HBsAg, HBeAg, HBcAg and HCVAg with the absence of the cross reaction. In the model arrays, the anti-IgG as low as 3 ng/ml could be detected. The data for comparing the protein chip assay with ELISA indicated that no distinct difference (P > 0.05) existed between the results determined by our assay and ELISA respectively.

Conclusion

Results showed that our assay can be applied with serology for the detection of HBV and HCV antibodies rapidly and simultaneously in clinical detection.

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Article
Probable neuroimmunological link between Toxoplasma and cytomegalovirus infections and personality changes in the human host

Authors: Novotná Martina --- Hanusova Jitka --- Klose Jiří --- Preiss Marek --- et al.
DOI: 10.1186/1471-2334-5-54
Pages: 54
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Abstract

Abstract

Background

Recently, a negative association between Toxoplasma-infection and novelty seeking was reported. The authors suggested that changes of personality trait were caused by manipulation activity of the parasite, aimed at increasing the probability of transmission of the parasite from an intermediate to a definitive host. They also suggested that low novelty seeking indicated an increased level of the neurotransmitter dopamine in the brain of infected subjects, a phenomenon already observed in experimentally infected rodents. However, the changes in personality can also be just a byproduct of any neurotropic infection. Moreover, the association between a personality trait and the toxoplasmosis can even be caused by an independent correlation of both the probability of Toxoplasma-infection and the personality trait with the third factor, namely with the size of living place of a subject. To test these two alternative hypotheses, we studied the influence of another neurotropic pathogen, the cytomegalovirus, on the personality of infected subjects, and reanalyzed the original data after the effect of the potential confounder, the size of living place, was controlled.

Methods

In the case-control study, 533 conscripts were tested for toxoplasmosis and presence of anti-cytomegalovirus antibodies and their novelty seeking was examined with Cloninger's TCI questionnaire. Possible association between the two infections and TCI dimensions was analyzed.

Results

The decrease of novelty seeking is associated also with cytomegalovirus infection. After the size of living place was controlled, the effect of toxoplasmosis on novelty seeking increased. Significant difference in novelty seeking was observed only in the largest city, Prague.

Conclusion

Toxoplasma and cytomegalovirus probably induce a decrease of novelty seeking. As the cytomegalovirus spreads in population by direct contact (not by predation as with Toxoplasma), the observed changes are the byproduct of brain infections rather than the result of manipulation activity of a parasite. Four independent lines of indirect evidence, namely direct measurement of neurotransmitter concentration in mice, the nature of behavioral changes in rodents, the nature of personality changes in humans, and the observed association between schizophrenia and toxoplasmosis, suggest that the changes of dopamine concentration in brain could play a role in behavioral changes of infected hosts.

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Article
Subclinical iron deficiency is a strong predictor of bacterial vaginosis in early pregnancy

Authors: Verstraelen Hans --- Delanghe Joris --- Roelens Kristien --- Blot Stijn --- et al.
DOI: 10.1186/1471-2334-5-55
Pages: 55
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Abstract

Abstract

Background

Bacterial vaginosis (BV) is the single most common vaginal infection in women of childbearing age and associated with a sizeable infectious disease burden among both non-pregnant and pregnant women, including a significantly elevated risk of adverse pregnancy outcome. Overall, little progress has been made in identifying causal factors involved in BV acquisition and persistence. We sought to evaluate maternal iron status in early pregnancy as a putative risk factor for BV, considering that micronutrients, and iron deficiency in particular, affect the host response against bacterial colonization, even in the setting of mild micronutrient deficiencies.

Methods

In a nested case-control study, we compared maternal iron status at entry to prenatal care (mean gestational age 9.2 ± 2.6 weeks) between eighty women with healthy vaginal microflora and eighteen women with vaginosis-like microflora. Vaginal microflora status was assessed by assigning a modified Nugent score to a Gram-stained vaginal smear. Maternal iron status was assayed by an array of conventional erythrocyte and serum indicators for iron status assessment, but also by more sensitive and more specific indicators of iron deficiency, including soluble transferrin receptors (sTfR) as an accurate measure of cellular and tissue iron deficiency and the iron deficiency log10[sTfR/ferritin] index as the presently most accurate measure of body storage iron available.

Results

We found no statistically significant correlation between vaginal microflora status and routinely assessed iron parameters. In contrast, a highly significant difference between the healthy and vaginosis-like microflora groups of women was shown in mean values of sTfR concentrations (1.15 ± 0.30 mg/L versus 1.37 ± 0.38 mg/L, p = 0.008) and in mean iron deficiency log10[sTfR/ferritin] index values (1.57 ± 0.30 versus 1.08 ± 0.56, p = 0.003), indicating a strong association between iron deficiency and vaginosis-like microflora. An sTfR concentration >1.45 mg/L was associated with a 3-fold increased risk (95%CI: 1.4–6.7) of vaginosis-like microflora and after controlling for maternal age, gestational length, body mass, parity, and smoking habits with an adjusted odds ratio of 4.5 (95%CI: 1.4–14.2).

Conclusion

We conclude that subclinical iron deficiency, presumably resulting from inadequate preconceptional iron supplies, is strongly and independently associated with vaginosis-like microflora during early pregnancy.

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Article
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review

Authors: Pham Ba' --- Duval Bernard --- De Serres Gaston --- Gilca Vladimir --- et al.
DOI: 10.1186/1471-2334-5-56
Pages: 56
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Abstract

Abstract

Background

In Canada – a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, complex, and changing. This systematic review aimed to 1) estimate age-specific prevalence of HAV antibody in Canada and 2) evaluate infection-associated risk factors.

Methods

MEDLINE (1966–2005) and EMBASE (1980–2005) were searched to identify relevant studies for the systematic review. Archives for the Canada Diseases Weekly Report (1975–1991) and Canada Communicable Disease Report (1992–2005) were searched for relevant public health reports. Data were abstracted for study and participants' characteristics, age-specific prevalence, and risk factors.

Results

A total of 36 reports describing 34 unique studies were included.

The seroprevalence in Canadian-born children was approximately 1% in ages 8–13, 1–6% in 20–24, 10% in 25–29, 17% in 30–39, and increased subsequently. In age groups below 20 and 20–29, age-specific seroprevalence generally remained constant for studies conducted across geographic areas and over time.

Compared to Canadian-born individuals, subjects born outside Canada were approximately 6 times more likely to be seropositive (relative risk: 5.7 [95% CI 3.6, 9.0]). Travel to high risk areas in individuals aged 20–39 was associated with a significant increase in anti-HAV seropositivity (RR 2.8 [1.4, 5.5]). Compared to heterosexuals, men having sex with men were only at a marginally higher risk (adjusted odds ratio 2.4 [0.9, 6.1]). High risk for seropositivity was also observed for Canadian First Nations and Inuit populations.

Conclusion

Results from the current systematic review show that in this low endemicity country, disease acquisition occurs in adulthood rather than childhood. The burden of disease is high; approximately 1 in 10 Canadians had been infected by ages 24–29. The increase in prevalence in young adults coincides with disease importation and increasing frequency of risk factors, most likely behavioral-related ones.

Gaps in seroprevalence data were identified rendering the application of current immunization recommendations difficult. A nationwide prevalence survey for all Canadians is needed. This is essential to quantify the effectiveness of current recommendations and conduct cost-effectiveness evaluations of alternative immunization programs, if necessary.

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Article
Hospitalization for pertussis: profiles and case costs by age

Authors: O'Brien Judith A --- Caro J Jaime
DOI: 10.1186/1471-2334-5-57
Pages: 57
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Abstract

Abstract

Background

Pertussis, a highly contagious respiratory illness, affects people of all ages and can have serious clinical consequences. It has been reported that from 1997–2000, 20% of all pertussis cases required hospitalization in the US. This analysis examined demographics, case fatality rate, resource use and costs of hospital care related to pertussis by age.

Methods

ICD-9 codes (033.0, 033.9) were used to identify cases of pertussis in hospital discharge databases from roughly 1,000 US hospitals in 4 states (California, Florida, Maryland, Massachusetts). Data from 1996–1999 were examined by age group. Separate analyses were done for infants (<1 year) and children (1–11 years); however, adolescent and adult cases were combined into one group (12+ years), due to the small number of cases. Databases were used to determine demographics, health service utilization and care costs. Cost estimates include accommodations, ancillary and physician services, reported in 2002 US$.

Results

Of the 2,518 cases identified, 90% were infants. The inpatient case fatality rate was <1%. Of survivors, 99% were discharged home (6% with home health care); 1% required further sub-acute inpatient care. For the 2,266 infants, the mean LOS was 6 days at a cost of $9,586 per stay. Children (n = 191) had a mean LOS of 3.7 and cost of $4,729; adolescents/adults (n = 61, mean age 40 years) stayed on average 3.4 days with a cost of $5,683 per hospitalization.

Conclusion

Infants are responsible for the bulk of hospitalizations and generate higher inpatient costs. Costly hospital care occurs, however, in patients with pertussis at all ages.

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Article
Incidence and risk factors for liver enzyme elevation during highly active antiretroviral therapy in HIV-HCV co-infected patients: results from the Italian EPOKA-MASTER Cohort

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Abstract

Abstract

Background

The risk of hepatotoxicity associated with different highly active antiretroviral therapy (HAART) regimens (containing multiple-protease inhibitors, single-protease inhibitors or non nucleoside reverse transcriptase inhibitors) in HIV-HCV co-infected patients has not been fully assessed.

Methods

Retrospective analysis of a prospective cohort of 1,038 HIV-HCV co-infected patients who commenced a new HAART in the Italian MASTER database. Patients were stratified into naïve and experienced to antiretroviral therapy before starting the study regimens. Time to grade ≥III hepatotoxicity (as by ACTG classification) was the primary outcome. Secondary outcome was time to grade IV hepatotoxicity.

Results

Incidence of grade ≥III hepatotoxicity was 17.71 per 100 patient-years (p-yr) of follow up in naïve patient group and 8.22 per 100 p-yrs in experienced group (grade IV: 4.13 per 100 p-yrs and 1.08 per 100 p-yrs, respectively). In the latter group, the only independent factors associated with shorter time to the event at proportional hazards regression model were: previous liver transaminase elevations to grade ≥III, higher baseline alanine amino-transferase values, and use of a non nucleoside reverse transcriptase inhibitor based regimen. In the naive group, baseline aspartate transaminase level was associated with the primary outcome.

Conclusion

Use of a single or multiple protease inhibitor based regimen was not associated with risk of hepatotoxicity in either naïve or experienced patient groups to a statistically significant extent. A cautious approach with strict monitoring should be applied in HIV-HCV co-infected experienced patients with previous liver transaminase elevations, higher baseline alanine amino-transferase values and who receive regimens containing non nucleoside reverse transcriptase inhibitors.

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Article
Bacteriophage- based tests for the detection of Mycobacterium tuberculosis in clinical specimens: a systematic review and meta- analysis

Authors: Kalantri Shriprakash --- Pai Madhukar --- Pascopella Lisa --- Riley Lee --- et al.
DOI: 10.1186/1471-2334-5-59
Pages: 59
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Abstract

Abstract

Background

Sputum microscopy, the most important conventional test for tuberculosis, is specific in settings with high burden of tuberculosis and low prevalence of non tuberculous mycobacteria. However, the test lacks sensitivity. Although bacteriophage-based tests for tuberculosis have shown promising results, their overall accuracy has not been systematically evaluated.

Methods

We did a systematic review and meta-analysis of published studies to evaluate the accuracy of phage-based tests for the direct detection of M. tuberculosis in clinical specimens. To identify studies, we searched Medline, EMBASE, Web of science and BIOSIS, and contacted authors, experts and test manufacturers. Thirteen studies, all based on phage amplification method, met our inclusion criteria. Overall accuracy was evaluated using forest plots, summary receiver operating (SROC) curves, and subgroup analyses.

Results

The data suggest that phage-based assays have high specificity (range 0.83 to 1.00), but modest and variable sensitivity (range 0.21 to 0.88). The sensitivity ranged between 0.29 and 0.87 among smear-positive, and 0.13 to 0.78 among smear-negative specimens. The specificity ranged between 0.60 and 0.88 among smear-positive and 0.89 to 0.99 among smear-negative specimens. SROC analyses suggest that overall accuracy of phage-based assays is slightly higher than smear microscopy in direct head-to-head comparisons.

Conclusion

Phage-based assays have high specificity but lower and variable sensitivity. Their performance characteristics are similar to sputum microscopy. Phage assays cannot replace conventional diagnostic tests such as microscopy and culture at this time. Further research is required to identify methods that can enhance the sensitivity of phage-based assays without compromising the high specificity.

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Article
Kocuria kristinae infection associated with acute cholecystitis

Authors: Ma Edmond SK --- Wong Chris LP --- Lai Kristi TW --- Chan Edmond CH --- et al.
DOI: 10.1186/1471-2334-5-60
Pages: 60
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Abstract

Abstract

Background

Kocuria, previously classified into the genus of Micrococcus, is commonly found on human skin. Two species, K. rosea and K. kristinae, are etiologically associated with catheter-related bacteremia.

Case presentation

We describe the first case of K. kristinae infection associated with acute cholecystitis. The microorganism was isolated from the bile of a 56-year old Chinese man who underwent laparoscopic cholecystectomy. He developed post-operative fever that resolved readily after levofloxacin treatment.

Conclusion

Our report of K. kristinae infection associated with acute cholecystitis expands the clinical spectrum of infections caused by this group of bacteria. With increasing number of recent reports describing the association between Kocuria spp. and infectious diseases, the significance of their isolation from clinical specimens cannot be underestimated. A complete picture of infections related to Kocuria spp. will have to await the documentation of more clinical cases.

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Article
Lack of association between serological evidence of past Coxiella burnetii infection and incident ischaemic heart disease: nested case-control study

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Abstract

Background

Coxiella burnetii causes the common worldwide zoonotic infection, Q fever. It has been previously suggested that patients who had recovered from acute Q fever (whether symptomatic or otherwise) may be at increased risk of ischaemic heart disease. We undertook this study to determine if past infection with Coxiella burnetii, the aetiological agent of Q fever, is a risk factor for the subsequent development of ischaemic heart disease.

Methods

A nested case-control study within the Prospective Epidemiological Study of Myocardial Infarction (PRIME). The PRIME study is a cohort study of 10,593 middle-aged men undertaken in France and Northern Ireland in the 1990s. A total of 335 incident cases of ischaemic heart disease (IHD) were identified and each case was matched to 2 IHD free controls. Q fever seropositivity was determined using a commercial IgG ELISA method.

Results

Seroprevalence of Q fever in the controls from Northern Ireland and France were 7.8% and 9.0% respectively. No association was seen between seropositivity and age, smoking, lipid levels, or inflammatory markers. The unadjusted odds ratio (95% CI) for Q fever seropositivity in cases compared to controls was 0.95 (0.59, 1.57). The relationship was substantially unaltered following adjustment for cardiovascular risk factors and potential confounders.

Conclusion

Serological evidence of past infection with C. burnetii was not found to be associated with an increased risk of IHD.

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Article
A commercial line probe assay for the rapid detection of rifampicin resistance in Mycobacterium tuberculosis: a systematic review and meta-analysis

Authors: Morgan Maureen --- Kalantri Shriprakash --- Flores Laura --- Pai Madhukar
DOI: 10.1186/1471-2334-5-62
Pages: 62
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Abstract

Abstract

Background

Mycobacterium tuberculosis is a leading cause of death worldwide. In multi-drug resistant tuberculosis (MDR-TB) infectiousness is frequently prolonged, jeopardizing efforts to control TB. The conventional tuberculosis drug susceptibility tests are sensitive and specific, but they are not rapid. The INNO-LiPA Rif. TB ® (LiPA) is a commercial line probe assay designed to rapidly detect rifampicin resistance, a marker of MDR-TB. Although LiPA has shown promising results, its overall accuracy has not been systematically evaluated.

Methods

We did a systematic review and meta-analysis to evaluate the accuracy of LiPA for the detection of rifampicin-resistant tuberculosis among culture isolates and clinical specimens. We searched Medline, Embase, Web of Science, BIOSIS, and Google Scholar, and contacted authors, experts and the manufacturer. Fifteen studies met our inclusion criteria. Of these, 11 studies used culture isolates, one used clinical specimens, and three used both. We used a summary receiver operating characteristic (SROC) curve and Q* index to perform meta-analysis and summarize diagnostic accuracy.

Results

Twelve of 14 studies that applied LiPA to isolates had sensitivity greater than 95%, and 12 of 14 had specificity of 100%. The four studies that applied LiPA directly to clinical specimens had 100% specificity, and sensitivity that ranged between 80% and 100%. The SROC curve had an area of 0.99 and Q* of 0.97.

Conclusion

LiPA is a highly sensitive and specific test for the detection of rifampicin resistance in culture isolates. The test appears to have relatively lower sensitivity when used directly on clinical specimens. More evidence is needed before LiPA can be used to detect MDR-TB among populations at risk in clinical practice.

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Article
A nested-PCR with an Internal Amplification Control for the detection and differentiation of Bartonella henselae and B. clarridgeiae: An examination of cats in Trinidad

Authors: Rampersad Joanne N --- Watkins John D --- Samlal Michael S --- Deonanan Raymond --- et al.
DOI: 10.1186/1471-2334-5-63
Pages: 63
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Abstract

Abstract

Background

Bartonella species are bacterial blood parasites of animals capable of causing disease in both animals and man. Cat-Scratch Disease (CSD) in humans is caused mainly by Bartonella henselae and is acquired from the cat, which serves as a reservoir for the bacteria. A second species, B. clarridgeiae is also implicated in the disease. Diagnosis of Bartonellosis by culture requires a week or more of incubation on enriched media containing blood, and recovery is often complicated by faster growing contaminating bacteria and fungi. PCR has been explored as an alternative to culture for both the detection and species identification of Bartonella, however sensitivity problems have been reported and false negative reactions due to blood inhibitors have not generally been addressed in test design.

Methods

A novel, nested-PCR was designed for the detection of Bartonella henselae and B. clarridgeiae based on the strategy of targeting species-specific size differences in the 16S-23S rDNA intergenic regions. An Internal Amplification Control was used for detecting PCR inhibition. The nested-PCR was utilized in a study on 103 blood samples from pet and stray cats in Trinidad.

Results

None of the samples were positive by primary PCR, but the Nested-PCR detected Bartonella in 32/103 (31%) cats where 16 were infected with only B. henselae, 13 with only B. clarridgeiae and 3 with both species. Of 22 stray cats housed at an animal shelter, 13 (59%) were positive for either or both species, supporting the reported increased incidence of Bartonella among feral cats.

Conclusion

The usefulness of a single PCR for the detection of Bartonella henselae and B. clarridgeiae in the blood of cats is questionable. A nested-PCR offers increased sensitivity over a primary PCR and should be evaluated with currently used methods for the routine detection and speciation of Bartonella henselae and B. clarridgeiae. In Trinidad, B. henselae and B. clarridgeiae are the predominant species in cats and infection appears highest with stray cats, however B. clarridgeiae may be present at levels similar to that of B. henselae in the pet population.

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Article
Inducible nitric oxide synthase (iNOS) expression in monocytes during acute Dengue Fever in patients and during in vitro infection

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Abstract

Abstract

Mononuclear phagocytes are considered to be main targets for Dengue Virus (DENV) replication. These cells are activated after infection, producing proinflammatory mediators, including tumour-necrosis factor-α, which has also been detected in vivo. Nitric oxide (NO), usually produced by activated mononuclear phagocytes, has antimicrobial and antiviral activities.

Methods

The expression of DENV antigens and inducible nitric oxide synthase (iNOS) in human blood isolated monocytes were analysed by flow cytometry using cells either from patients with acute Dengue Fever or after DENV-1 in vitro infection. DENV-1 susceptibility to iNOS inhibition and NO production was investigated using NG-methyl L-Arginine (NGMLA) as an iNOS inhibitor, which was added to DENV-1 infected human monocytes, and sodium nitroprussiate (SNP), a NO donor, added to infected C6/36 mosquito cell clone. Viral antigens after treatments were detected by flow cytometry analysis.

Results

INOS expression in activated monocytes was observed in 10 out of 21 patients with Dengue Fever and was absent in cells from ten healthy individuals. DENV antigens detected in 25 out of 35 patients, were observed early during in vitro infection (3 days), significantly diminished with time, indicating that virus replicated, however monocytes controlled the infection. On the other hand, the iNOS expression was detected at increasing frequency in in vitro infected monocytes from three to six days, exhibiting an inverse relationship to DENV antigen expression. We demonstrated that the detection of the DENV-1 antigen was enhanced during monocyte treatment with NGMLA. In the mosquito cell line C6/36, virus detection was significantly reduced in the presence of SNP, when compared to that of untreated cells.

Conclusion

This study is the first to reveal the activation of DENV infected monocytes based on induction of iNOS both in vivo and in vitro, as well as the susceptibility of DENV-1 to a NO production.

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Article
Correction: Investigation of Staphylococcus strains with heterogeneous resistance to glycopeptides in a Turkish university hospital

Authors: Nakipoglu Yasar --- Derbentli Sengul --- Cagatay Atahan A --- Katranci Handan
DOI: 10.1186/1471-2334-5-65
Pages: 65
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Article
Does age acquired immunity confer selective protection to common serotypes of Campylobacter jejuni?

Authors: Miller Gordon --- Dunn Geoff M --- Reid Thomas MS --- Ogden Iain D --- et al.
DOI: 10.1186/1471-2334-5-66
Pages: 66
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Abstract

Abstract

Background

Campylobacter infection is a major cause of bacterial gastrointestinal disease. Exposure to Campylobacter is known to produce an immune response in humans that can prevent future symptomatic infections. Further, studies of the general population have shown that seroprevalence to Campylobacter increases with age.

Methods

A large collection of serotyped Campylobacter isolates, obtained from human clinical faecal samples, were analysed by comparing the ratio of uncommon to common serotypes by different age groups, using χ2 tests.

Results

We have identified that older age groups, as well as having generally lower incidence, are significantly less likely to be infected by the more common serotypes.

Conclusion

These results are indicative of acquired immunity, however, further studies are needed to rule out the confounding effects of the variations in exposure pathways experienced by different age groups.

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Article
Safety and tolerability of nevirapine-based antiretroviral therapy in HIV-infected patients receiving fluconazole for cryptococcal prophylaxis: a retrospective cohort study

Authors: Manosuthi Weerawat --- Chumpathat Nopphanath --- Chaovavanich Achara --- Sungkanuparph Somnuek
DOI: 10.1186/1471-2334-5-67
Pages: 67
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Abstract

Abstract

Background

To compare the adverse events after initiation of nevirapine-based ART among HIV-infected patients who did not receive fluconazole (group A), received fluconazole 400 mg/week (group B), and received fluconazole 200 mg/day (group C).

Methods

A retrospective cohort study was conducted among HIV-infected patients who began NVP-based ART between December 2003 and September 2004. Patients were followed up for 6 months. Clinical hepatitis, elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (> 3 times from baseline), and skin rashes were studied.

Results

There were 686 patients; 225, 392, and 69 patients in group A, B, and C, respectively. Baseline characteristics including age, previous opportunistic infections, use of antituberculous drugs, and baseline aminotransferase levels among the three groups were similar. Group C had a higher proportion of men (p = 0.016). Baseline median (IQR) CD4 cell counts were 85 (21–159), 18 (7–48), and 16 (5–35) cell/mm3 in group A, B, and C, respectively (p < 0.001). Of 2/225 (0.9%), 4/392 (1.0%), and 0/69 (0%) patients in group A, B, and C developed clinical hepatitis (p = 0.705). There were no significant difference of elevated AST or ALT among the three groups (p > 0.05). By logistic regression, receiving fluconazole was not predictive of clinical hepatitis, elevated aminotransferase, or skin rashes. At 6 months after initiating NVP, 174 (77.3%) patients in group A, 309 (78.8%) patients in group B, and 58 (84.1%) patients in group C remained on NVP.

Conclusion

Initiation of NVP-based ART among Thais with advance HIV disease receiving fluconazole is safe and well-tolerated. nevirapine should not be contraindicated for patients receiving fluconazole for treatment or prophylaxis of cryptococcosis.

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Article
Arcanobacterium haemolyticum associated with pyothorax: case report

Authors: Parija Subhash --- Kaliaperumal Venkatesh --- Kumar Saka --- Sujatha Sistla --- et al.
DOI: 10.1186/1471-2334-5-68
Pages: 68
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Abstract

Arcanobacterium haemolyticum has an established role in the etiology of human pharyngitis. There are increasing reports of systemic infections caused by this organism. From India, we report the first case of Arcanobacterium haemolyticum causing pyothorax in an immunocompetent adolescent male patient. The probable mode of infection is also discussed. The role of A. hemolyticum as an animal pathogen needs further study.

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Article
Different patterns of HIV-1 DNA after therapy discontinuation

Authors: Re Maria Carla --- Vitone Francesca --- Sighinolfi Laura --- Schiavone Pasqua --- et al.
DOI: 10.1186/1471-2334-5-69
Pages: 69
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Abstract

Abstract

Background

By persisting in infected cells for a long period of time, proviral HIV-1 DNA can represent an alternative viral marker to RNA viral load during the follow-up of HIV-1 infected individuals. In the present study sequential blood samples of 10 patients under antiretroviral treatment from 1997 with two NRTIs, who refused to continue any antiviral regimen, were analyzed for 16 – 24 weeks to study the possible relationship between DNA and RNA viral load.

Methods

The amount of proviral DNA was quantified by SYBR green real-time PCR in peripheral blood mononuclear cells from a selected group of ten patients with different levels of plasmatic viremia (RNA viral load).

Results

Variable levels of proviral DNA were found without any significant correlation between proviral load and plasma HIV-1 RNA levels. Results obtained showed an increase or a rebound in viral DNA in most patients, suggesting that the absence of therapy reflects an increase and/or a persistence of cells containing viral DNA.

Conclusion

Even though plasma HIV RNA levels remain the basic parameter to monitor the intensity of viral replication, the results obtained seem to indicate that DNA levels could represent an adjunct prognostic marker in monitoring HIV-1 infected subjects.

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Article
Mortality following Campylobacter infection: a registry-based linkage study

Authors: Ternhag Anders --- Törner Anna --- Svensson Åke --- Giesecke Johan --- et al.
DOI: 10.1186/1471-2334-5-70
Pages: 70
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Abstract

Abstract

Background

Campylobacteriosis is one of the most commonly identified causes of bacterial diarrheal disease and a common cause of gastroenteritis in travellers from developed nations. Despite the widespread occurrence, there is little information on Campylobacter mortality.

Methods

Mortality among a cohort of Campylobacter cases were compared with the general population 0–1, 1–3, 3–12 and more than 12 month after the onset of the illness. The cases were sub-grouped according to if they had been infected domestically or abroad.

Results

The standardized mortality ratio for cases infected domestically was 2.9 (95% CI: 1.9–4.0) within the first month following the illness. The risk then gradually diminished and approached 1.0 after one year or more have passed since the illness. This initial excess risk was not attributable to any particular age group (such as the oldest).

In contrast, for those infected abroad, a lower standardized mortality ratio 0.3 (95% CI: 0.04–0.8) was shown for the first month after diagnosis compared to what would be expected in the general population.

Conclusion

Infection with Campylobacter is associated with an increased short-term risk of death among those who were infected domestically. On the contrary, for those infected abroad a lower than expected risk of death was evident. We suggest that the explanation behind this is a "healthy traveler effect" among imported cases, and effects of a more frail than average population among domestic cases.

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Article
Effects of type and level of training on variation in physician knowledge in the use and acquisition of blood cultures: a cross sectional survey

Authors: Parada Jorge P --- Schwartz David N --- Schiff Gordon D --- Weiss Kevin B
DOI: 10.1186/1471-2334-5-71
Pages: 71
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Abstract

Abstract

Background

Blood culture (BCX) use is often sub-optimal, and is a user-dependent diagnostic test. Little is known about physician training and BCX-related knowledge. We sought to assess variations in caregiver BCX-related knowledge, and their relation to medical training.

Methods

We developed and piloted a self-administered BCX-related knowledge survey instrument. Expert opinion, literature review, focus groups, and mini-pilots reduced > 100 questions in multiple formats to a final questionnaire with 15 scored content items and 4 covariate identifiers. This questionnaire was used in a cross-sectional survey of physicians, fellows, residents and medical students at a large urban public teaching hospital. The responses were stratified by years/level of training, type of specialty training, self-reported practical and theoretical BCX-related instruction. Summary scores were derived from participant responses compared to a 95% consensus opinion of infectious diseases specialists that matched an evidence based reference standard.

Results

There were 291 respondents (Attendings = 72, Post-Graduate Year (PGY) = 3 = 84, PGY2 = 42, PGY1 = 41, medical students = 52). Mean scores differed by training level (Attending = 85.0, PGY3 = 81.1, PGY2 = 78.4, PGY1 = 75.4, students = 67.7) [p ≤ 0.001], and training type (Infectious Diseases = 96.1, Medicine = 81.7, Emergency Medicine = 79.6, Surgery = 78.5, Family Practice = 76.5, Obstetrics-Gynecology = 74.4, Pediatrics = 74.0) [p ≤ 0.001]. Higher summary scores were associated with self-reported theoretical [p ≤ 0.001] and practical [p = 0.001] BCX-related training. Linear regression showed level and type of training accounted for most of the score variation.

Conclusion

Higher mean scores were associated with advancing level of training and greater subject-related training. Notably, house staff and medical students, who are most likely to order and/or obtain BCXs, lack key BCX-related knowledge. Targeted education may improve utilization of this important diagnostic tool.

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Article
Population-based laboratory surveillance for Giardia sp. and Cryptosporidium sp. infections in a large Canadian health region

Authors: Laupland Kevin B --- Church Deirdre L
DOI: 10.1186/1471-2334-5-72
Pages: 72
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Abstract

Abstract

Background

Giardia lamblia (intestinalis) and Cryptosporidium parvum are the two most important intestinal parasites infecting North Americans but there is a paucity of active population-based surveillance data from Canada. This study determined the incidence of and demographic risk factors for developing Giardia sp. and Cryptosporidium sp. infections in a general Canadian population.

Methods

Population-based laboratory surveillance was conducted among all residents of the Calgary Health Region (CHR; population ≅ 1 million) during May 1, 1999 and April 30, 2002.

Results

Giardia sp. infection occurred at a rate of 19.6 per 100,000 populations per year. Although the yearly incidence was stable, a significant seasonal variation was observed with a peak in late summer to early fall. Males were at higher risk for development of this infection as compared to females (21.2 vs. 17.9 per 100,000/yr; relative risk (RR) 1.19; 95% confidence interval (CI), 1.00–1.40, p = 0.047), and there was a significant decrease in risk associated with an increasing age. Cryptosporidium sp. infection occurred at an overall rate of 6.0 per 100,000 populations per year although a large outbreak of Cryptosporidium sp. infections occurred in the second half of the summer of 2001. During August and September of 2001, the incidence of cryptosporidiosis was 55.1 per 100,000 per year as compared to 3.1 per 100,000 per year for the remainder of the surveillance period (p < 0.0001). Cryptosporidiosis was largely a disease of children with an incidence of 17.8 per 100,000 per year occurring among those aged < 20 years of age compared to 1.25 per 100,000 per year for adults ≥ 20 years of age (RR 14.19; 95% CI, 9.77–21.11; p < 0.0001).

Conclusion

This study provides important information on the occurrence and demographic risk groups for acquisition of giardiasis and cryptosporidiosis in a non-selected Canadian population.

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Article
Generation of human antibody fragments recognizing distinct epitopes of the nucleocapsid (N) SARS-CoV protein using a phage display approach

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Abstract

Abstract

Background

Severe acute respiratory syndrome (SARS)-CoV is a newly emerging virus that causes SARS with high mortality rate in infected people. Successful control of the global SARS epidemic will require rapid and sensitive diagnostic tests to monitor its spread, as well as, the development of vaccines and new antiviral compounds including neutralizing antibodies that effectively prevent or treat this disease.

Methods

The human synthetic single-chain fragment variable (scFv) ETH-2 phage antibody library was used for the isolation of scFvs against the nucleocapsid (N) protein of SARS-CoV using a bio panning-based strategy. The selected scFvs were characterized under genetics-molecular aspects and for SARS-CoV N protein detection in ELISA, western blotting and immunocytochemistry.

Results

Human scFv antibodies to N protein of SARS-CoV can be easily isolated by selecting the ETH-2 phage library on immunotubes coated with antigen. These in vitro selected human scFvs specifically recognize in ELISA and western blotting studies distinct epitopes in N protein domains and detect in immunohistochemistry investigations SARS-CoV particles in infected Vero cells.

Conclusion

The human scFv antibodies isolated and described in this study represent useful reagents for rapid detection of N SARS-CoV protein and SARS virus particles in infected target cells.

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Article
Leprosy & gangrene: A rare association; role of anti phospholipid antibodies

Authors: Akerkar Shashank M --- Bichile Lata S
DOI: 10.1186/1471-2334-5-74
Pages: 74
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Abstract

Abstract

Background

Leprosy still remains an important public health problem for many parts of the world. An association of gangrene with leprosy is a rare one & can have a number of causative mechanisms. We present a case with Leprosy & gangrene with positive anti phopholipid antibody titers.

Case presentation

A 50-year-old non-diabetic, non-hypertensive lady presented with 2 months history of progressive gangrene of bilateral toes. She was found to have madarosis & hypopigmented, hypoaesthetic macular lesions on the upper limb & thighs. Bilateral ulnar & popliteal nerves were thickened. A skin biopsy of the lesions revealed borderline tuberculoid leprosy, slit skin smears revealed a bacteriological index of 1+. She did not have any evidence of thromboembolic episode or atherosclerosis. ACLA was positive at presentation & also on another occasion 6 weeks later. ACLAs were of the IgM type on both occasions. Lupus Anticoagulant & β2 GPI antibody were negative. DOPPLER of the lower limb arteries did not reveal any abnormality. Patient was successfully treated with multi-drug antileprotics & anticoagulants.

Conclusion

Infectious APLAs should be recognized as a cause of thrombosis in Leprosy. Appropriate anticoagulation can salvage limb function.

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Article
Dog filariosis in the Lazio region (Central Italy): first report on the presence of Dirofilaria repens

Authors: Scaramozzino Paola --- Gabrielli Simona --- Di Paolo Michele --- Sala Marcello --- et al.
DOI: 10.1186/1471-2334-5-75
Pages: 75
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Abstract

Abstract

Background

Epidemiological investigations were carried out in the Lazio Region to assess the status of canine filariosis and to evaluate the actual risk for veterinary and medical public health.

Methods

Since August 2001 to June 2003, a total of 972 canine blood samples, collected in public kennels and from private owners animals of the 5 Provinces of the Region, were tested. The presence of filarial parasites was evaluated by microscopy and bio-molecular techniques; the species identification was performed by means of the same diagnostic tools.

Results

A total of 17/972 (1.75%; 95%CI 1.06%–2.85%) blood samples were parasitized by D. repens,13 out them drawn by dogs resident in the Province of Roma, and 4 in the other provinces. Multivariate analysis was performed in order to evaluate the association between filariosis and risk factors. The origin from coastal territories seems to be a significant risk factor to acquire the infection.

Conclusion

This is the first report of canine filariosis in the Lazio Region, where D. repens was before reported only in foxes. The risk of human zoonotic infection is stressed, and the absence of other filarial species is discussed

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Article
Use of a nested PCR-enzyme immunoassay with an internal control to detect Chlamydophila psittaci in turkeys

Authors: Van Loock Marnix --- Verminnen Kristel --- Messmer Trudy O --- Volckaert Guido --- et al.
DOI: 10.1186/1471-2334-5-76
Pages: 76
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Abstract

Abstract

Background

Laboratory diagnosis of Chlamydophila psittaci, an important turkey respiratory pathogen, is difficult. To facilitate the diagnosis, a nested PCR-enzyme immunoassay (PCR-EIA) was developed to detect the Cp. psittaci outer membrane protein A (ompA) gene in pharyngeal swabs.

Methods

The fluorescein-biotin labelled PCR products were immobilized on streptavidin-coated microtiter plates and detected with anti-fluorescein peroxidase conjugate and a colorimetric substrate. An internal inhibition control was included to rule out the presence of inhibitors of DNA amplification. The diagnostic value of the ompA nested PCR-EIA in comparison to cell culture and a 16S-rRNA based nested PCR was assessed in pharyngeal turkey swabs from 10 different farms experiencing respiratory disease.

Results

The sensitivity of the nested PCR-EIA was established at 0.1 infection forming units (IFU). Specificity was 100%. The ompA nested PCR-EIA was more sensitive than the 16S-rRNA based nested PCR and isolation, revealing 105 out of 200 (52.5%) positives against 13 and 74 for the latter two tests, respectively. Twenty-nine (23.8%) out of 122 ompA PCR-EIA negatives showed the presence of inhibitors of DNA amplification, although 27 of them became positive after diluting (1/10) the specimens in PCR buffer or after phenol-chloroform extraction and subsequent ethanol precipitation.

Conclusion

The present study stresses the need for an internal control to confirm PCR true-negatives and demonstrates the high prevalence of chlamydiosis in Belgian turkeys and its potential zoonotic risk. The ompA nested PCR-EIA described here is a rapid, highly sensitive and specific diagnostic assay and will help to facilitate the diagnosis of Cp. psittaci infections in both poultry and man.

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Article
Prevalence of human papillomavirus cervical infection in an Italian asymptomatic population

Authors: Centurioni Maria G --- Puppo Andrea --- Merlo Domenico F --- Pasciucco Gennaro --- et al.
DOI: 10.1186/1471-2334-5-77
Pages: 77
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Abstract

Abstract

Background

In the last decade many studies have definitely shown that human papillomaviruses (HPVs) are the major cause of cervical carcinogenesis and, in the last few years, HPV testing has been proposed as a new and more powerful tool for cervical cancer screening. This issue is now receiving considerable attention in scientific and non scientific press and HPV testing could be considered the most important change in this field since the introduction of cervical cytology. This paper reports our prevalence data of HPV infection collected in the '90s, while a follow up of these patients is ongoing.

Methods

For this study we used polymerase chain reaction (PCR) to search HPV DNA sequences in cervical cell scrapings obtained from 503 asymptomatic women attending regular cervical cancer screening program in the city of Genova, Italy. All patients were also submitted to a self-administered, standardized, questionnaire regarding their life style and sexual activity. On the basis of the presence of HPV DNA sequences women were separated into two groups: "infected" and "non infected" and a statistical analysis of the factors potentially associated with the infection group membership was carried out.

Results

The infection rate was 15.9% and the most frequent viral type was HPV 16.

Conclusion

Our HPV positivity rate (15.9%) was consistent to that reported by other studies on European populations.

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Article
GB virus-C – a virus without a disease: We cannot give it chronic fatigue syndrome

Authors: Jones James F --- Kulkarni Prasad S --- Butera Salvatore T --- Reeves William C
DOI: 10.1186/1471-2334-5-78
Pages: 78
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Abstract

Abstract

Background

Chronic fatigue syndrome (CFS) is an illness in search of an infectious etiology. GB virus-C (GBV-C) virus is a flavivirus with cell tropism and host defense induction qualities compatible with a role in producing the syndrome. The GBV-C genome is detectable in 4% of the population and 12% of the population is seropositive. The present study evaluated the association between infection with GBV and CFS.

Methods

We used a commercial EIA to detect antibodies against the GBV-C E2 protein and a quantitative real-time RT-PCR assay to detect active GBV-C infection. Sera were from a case control study of CFS in Atlanta, Georgia. The Fisher's exact two-tailed test was used for statistical analysis.

Results

Two of 12 CFS patients and one of 21 controls were seropositive for prior GBV-C infection and one control had viral RNA detected, indicating active infection. The results are not statistically different.

Conclusion

We found no evidence that active or past infection with GBV is associated with CFS.

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Article
Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model

Authors: Olmsted Stuart S --- Khanna Kristen V --- Ng Erina M --- Whitten Steven T --- et al.
DOI: 10.1186/1471-2334-5-79
Pages: 79
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Abstract

Abstract

Background

Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel®) to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model.

Methods

Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC) viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs.

Results

Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye). In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected) compared to saline (12 of 12 infected) and a control gel (5 of 7 infected).

Conclusion

These results suggest that physiologic or microbicide-induced acid immobilization and killing of infected white blood cells may be effective in preventing sexual transmission of cell-associated HIV.

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Article
Persistence of lipoatrophy after a four-year long interruption of antiretroviral therapy for HIV1 infection: case report

Authors: Parruti Giustino --- Toro Giuseppe
DOI: 10.1186/1471-2334-5-80
Pages: 80
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Abstract

Abstract

Background

HIV-infected patients on long-term highly active antiretroviral therapy often present peculiar patterns of fat redistribution, referred to as lipodystrophy. In spite of recent investigations, it is not known whether and to what extent the main features of lipodystrophy – that is lipoatrophy of peripheral fat at face, limbs and buttocks, as well as fat accumulation at breasts, abdomen and the dorso-cervical region – can be reversible once clinically manifest.

Case presentation

A 35 year old Caucasian HIV infected female developed severe diffuse lipodystrophy while on highly active antiretroviral therapy. A remarkable increase of breast size, fat accumulation at waist, and a fat pad on her lumbar spine were paralleled by progressive and disfiguring lipoatrophy of face, limbs and buttocks. The patient decided to interrupt her therapy after 20 months, with a stably suppressed viremia and a CD4 lymphocyte count >500/μL. She could carry on a safe treatment interruption for longer than 4 years. Most sites of fat accumulation switched to nearly normal appearance, whereas lipoatrophy was substantially unchanged at all affected sites.

Conclusion

our observation provides pictorial evidence that lipoatrophy may not be reversible even under ideal circumstances. Therefore, strategies to prevent lipoatrophy should be considered when defining therapeutic regimens for HIV infected patients, especially those at high risk.

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Article
Identification of moaA3 gene in patient isolates of Mycobacterium tuberculosis in Kerala, which is absent in M. tuberculosis H37Rv and H37Ra

Authors: Sarojini Suma --- Soman Smitha --- Radhakrishnan Indulakshmi --- Mundayoor Sathish
DOI: 10.1186/1471-2334-5-81
Pages: 81
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Abstract

Abstract

Background

Tuberculosis is endemic to developing countries like India. Though the whole genome sequences of the type strain M. tuberculosis H37Rv and the clinical strain M. tuberculosis CDC1551 are available, the clinical isolates from India have not been studied extensively at the genome level. This study was carried out in order to have a better understanding of isolates from Kerala, a state in southern India.

Results

A PCR based strategy was followed making use of the deletion region primers to understand the genome level differences between the type strain H37Rv and the clinical isolates of M. tuberculosis from Kerala. PCR analysis of patient isolates using RD1 region primers revealed the amplification of a 386 bp region, in addition to the expected 652 bp amplicon. Southern hybridization of genomic DNA with the 386 bp amplicon confirmed the presence of this new region in a majority of the patient isolates from Kerala. Sequence comparison of this amplicon showed close homology with the moaA3 gene of M. bovis. In M. bovis this gene is present in the RvD5 region, an IS6110 mediated deletion that is absent in M. tuberculosis H37Rv.

Conclusion

This study demonstrates the presence of moaA3 gene, that is absent in M. tuberculosis H37Rv and H37Ra, in a large number of local isolates. Whether the moaA3 gene provides any specific advantage to the field isolates of the pathogen is unclear. Field strains from Kerala have fewer IS6110 sequences and therefore are likely to have fewer IS6110 dependent rearrangements. But as deletions and insertions account for much of the genomic diversity of M. tuberculosis, the mechanisms of formation of sequence polymorphisms in the local isolates should be further examined. These results suggest that studies should focus on strains from endemic areas to understand the complexities of this pathogen.

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Article
Prosthetic valve endocarditis caused by Pseudomonas luteola

Authors: Casalta Jean-Paul --- Fournier Pierre-Edouard --- Habib Gilbert --- Riberi Alberto --- et al.
DOI: 10.1186/1471-2334-5-82
Pages: 82
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Abstract

Abstract

Background

Pseudomonas luteola has been recognized as an uncommon cause of bacteremia and of infections in patients with underlying medical disorders

Case presentation

We isolated P. luteola from blood cutures in a patient with prosthetic valve endocarditis developed 16 months after cardiac surgery.

Conclusion

P. luteola is a rare opportunistic agent, with a propensity of infecting valvular prostheses.

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Article
The 3' region of Human Papillomavirus type 16 early mRNAs decrease expression

Authors: Vinther Jeppe --- Rosenstierne Maiken W --- Kristiansen Karen --- Norrild Bodil
DOI: 10.1186/1471-2334-5-83
Pages: 83
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Abstract

Abstract

Background

High risk human papillomavirus (HR-HPV) infects mucosal surfaces and HR-HPV infection is required for development of cervical cancer. Accordingly, enforced expression of the early HR-HPV proteins can induce immortalisation of human cells. In most cervical cancers and cervical cancer cell lines the HR-HPV double stranded DNA genome has been integrated into the host cell genome.

Methods

We have used a retroviral GUS reporter system to generate pools of stably transfected HaCaT and SiHa cells. The HPV-16 early sequences that are deleted upon integration of the HPV-16 genome was inserted into the 3' UTR of the reporter mRNA. Pools containing thousands of independent integrations were tested for the steady state levels of the reporter mRNA by Real Time PCR and reporter protein by a GUS enzymatic activity assays. In addition, we tested the cellular distribution and half lives of the reporter mRNAs. The integrity of the reporter mRNAs were tested by northern blotting.

Results

We show that the 3' region of the HPV-16 early mRNAs (HPV-16 nucleotide (nt.) 2582–4214) act in cis to decrease both mRNA and protein levels. This region seems to affect transcription from the exogenous minimal CMV promoter or processing of the reporter mRNA. The observed repression was most pronounced at the protein level, suggesting that this sequence may also affect translation. For the HPV types: 2, 6, 11, 13, 18, 30, 31, and 35 we have investigated the regulatory effect of the regions corresponding to the HPV-16 nt. 3358–4214. For all types, except HPV-18, the region was found to repress expression by posttranscriptional mechanisms.

Conclusion

We find that the 3' region of HPV-16 early mRNAs interfere with gene expression. It is therefore possible that the deletion of the 3' part of early HPV-16 mRNAs occurring during cervical oncogenesis could contribute to transformation of cells through deregulation of the viral oncogene synthesis. Moreover, we find that the corresponding region from several other HPV types also repress expression, suggesting that the repression by this region may be a general feature of the HPV life cycle.

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Article
Use of "biokit HSV-2 Rapid Assay" to improve the positive predictive value of Focus HerpeSelect HSV-2 ELISA

Authors: Morrow Rhoda --- Friedrich David --- Meier Amalia --- Corey Lawrence
DOI: 10.1186/1471-2334-5-84
Pages: 84
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Abstract

Abstract

Background

Commercially available assays to detect antibodies to the herpes simplex virus type 2 (HSV-2)-specific glycoprotein gG-2 have markedly improved serologic diagnosis of HSV-2 infection. However, even tests with high specificity can have low positive predictive values in low prevalence populations. HSV-2 is a chronic, life-long viral infection that requires both medical attention and potential alterations in health care strategy. As such, the concern for false positive diagnoses is high confirmatory testing is routine for other viral serologies such as HIV and hepatitis C. We evaluated such a strategy for HSV-2 serology by using an easily performed commercial test, biokitHSV-2 rapid test ("Biokit"; Biokit USA, Lexington MA) as a confirmatory test for the widely used gG-2 specific serology ("Focus;" HerpeSelect HSV-2 ELISA; Focus Diagnostics, Cypress CA).

Methods

We tested 782 sera by Focus HSV-2 ELISA, Biokit, and the current gold standard test, Western blot (WB).

Results

The positive predictive value of the Focus HSV-2 ELISA increased from 80.5% to 95.6% when Biokit testing was performed on sera that were initially positive by Focus HSV-2 ELISA. Confirmatory testing increased the specificity markedly among sera with Focus EIA values between 1.1 and 3.5: only 35% of low positive (index values 1.1–3.5) Focus HSV-2 ELISA results confirmed as positive by Biokit and WB compared with 92% of those with index values >3.5. Mathematical modeling of the data resulted in expected positive predictive values over 98% for populations with antibody prevalences typical of clinical practices in the US and Europe.

Conclusion

Confirmatory Biokit testing of positive Focus HSV-2 ELISA results is fast, easy, and effective in reducing falsely positive HSV-2 antibody results. Patients, clinicians, and laboratories could benefit from the enhanced specificity of this simple HSV-2 serologic test combination.

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Article
Dementia-specific risks of scabies: Retrospective epidemiologic analysis of an unveiled nosocomial outbreak in Japan from 1989–90

Authors: Tsutsumi Masae --- Nishiura Hiroshi --- Kobayashi Toshio
DOI: 10.1186/1471-2334-5-85
Pages: 85
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Abstract

Abstract

Background

Although senile dementia patients in long-term care facilities are at leading risk of scabies, the epidemiologic characteristics of this disease have yet to be fully clarified. This study documents the findings of a ward-scale nosocomial outbreak in western Japan from 1989–90, for which permission to publish was only recently obtained.

Methods

A retrospective epidemiologic study was performed to identify specific risk factors of scabies among patients with dementia. Analyses were based on a review of medical and nursing records. All inpatients in the affected ward at the time of the outbreak were included in the study. Observational and analytical approaches were employed to assess the findings.

Results

Twenty of 65 inpatients in the ward met the case definition of scabies. The outbreak lasted for almost 10 months and as a result, the spatial distribution of infections showed no localized patterns in the latter phase of the outbreak. The duration of illness significantly decreased after initiation of control measures (P = 0.0067). Movement without assistance (Odds Ratio [OR] = 11.3; 95% Confidence Interval [CI]: 2.9, 44.8) and moving beyond the room (but within the ward) (OR = 4.1; 95% CI: 1.4, 12.5) were significantly associated with infection, while types of room (Western or Japanese) and sleeping arrangement (on beds or futons laid directly on the floor) appeared not to be risk factors.

Conclusion

Univariate analysis demonstrated the importance of patients' behaviours during daily activities in controlling scabies among senile dementia patients. The findings also support previous evidence that catching scabies from fomites is far less common. Moreover, since cognitive disorders make it difficult for individuals to communicate and understand the implications of risky contacts as well as treatment method, and given the non-specific nature of individual contacts that are often unpredictable, real-time observations might help improve control practices.

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Article
Extended Spectrum β-Lactamases among Gram-negative bacteria of nosocomial origin from an Intensive Care Unit of a tertiary health facility in Tanzania

Authors: Ndugulile Faustine --- Jureen Roland --- Harthug Stig --- Urassa Willy --- et al.
DOI: 10.1186/1471-2334-5-86
Pages: 86
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Abstract

Abstract

Background

Resistance to third generation cephalosporins due to acquisition and expression of extended spectrum β-lactamase (ESBL) enzymes among Gram-negative bacteria is on the increase. Presence of ESBL producing organisms has been reported to significantly affect the course and outcome of an infection. Therefore infections due to ESBL isolates continue to pose a challenge to infection management worldwide. The aim of this study was to determine the existence and to describe phenotypic and genotypic characteristics of ESBLs in an Intensive Care Unit (ICU) setting in Tanzania.

Methods

Between October 2002 and April 2003, clinical information and samples were collected from patients suspected to have nosocomial infections in an Intensive Care Unit of a tertiary hospital in Tanzania. The isolates were identified, tested for antimicrobial susceptibility and analysed for presence of ESBL genes.

Results

Thirty-nine Gram-negative bacteria were isolated from clinical samples of 39 patients. These isolates included 13 Escherichia coli, 12 Enterobacter spp, 5 Pseudomonas spp, 4 Proteus spp, 2 Klebsiella. pneumoniae, 2 Citrobacter freundii and 1 Chryseomonas luteola. Eleven (28.2%) of these isolates were ESBL producing. The ESBL genes characterised were SHV-12, SHV-28 and CTX-M-15. The ESBL producing isolates were more resistant to gentamicin and ciprofloxacin than non-ESBL producing isolates.

Conclusion

This study shows the presence of ESBL genes among Gram-negative bacteria in the ICU setting in Tanzania. There is a need to institute strict hospital infection control policy and a regular surveillance of resistance to antimicrobial agents.

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Article
A simple and rapid approach for screening of SARS-coronavirus genotypes: an evaluation study

Authors: Chung Grace TY --- Chiu Rossa WK --- Cheung Jo LK --- Jin Yongjie --- et al.
DOI: 10.1186/1471-2334-5-87
Pages: 87
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Abstract

Abstract

Background

The Severe Acute Respiratory Syndrome (SARS) was a newly emerged infectious disease which caused a global epidemic in 2002–2003. Sequence analysis of SARS-coronavirus isolates revealed that specific genotypes predominated at different periods of the epidemic. This information can be used as a footprint for tracing the epidemiology of infections and monitor viral evolution. However, direct sequencing analysis of a large number of clinical samples is cumbersome and time consuming. We present here a simple and rapid assay for the screening of SARS-coronavirus genotypes based on the use of fluorogenic oligonucleotide probes for allelic discrimination.

Methods

Thirty SARS patients were recruited. Allelic discrimination assays were developed based on the use of fluorogenic oligonucleotide probes (TaqMan). Genotyping of the SARS-coronavirus isolates obtained from these patients were carried out by the allelic discrimination assays and confirmed by direct sequencing.

Results

Genotyping based on the allelic discrimination assays were fully concordant with direct sequencing. All of the 30 SARS-coronavirus genotypes studied were characteristic of genotypes previously documented to be associated with the latter part of the epidemic. Seven of the isolates contained a previously reported major deletion but in patients not epidemiologically related to the previously studied cohort.

Conclusion

We have developed a simple and accurate method for the characterization and screening of SARS-coronavirus genotypes. It is a promising tool for the study of epidemiological relationships between documented cases during an outbreak.

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Article
A multicenter trial of the efficacy and safety of tigecycline versus imipenem/cilastatin in patients with complicated intra-abdominal infections [Study ID Numbers: 3074A1-301-WW; ClinicalTrials.gov Identifier: NCT00081744]

Authors: Oliva María E --- Rekha Arcot --- Yellin Albert --- Pasternak Jacyr --- et al.
DOI: 10.1186/1471-2334-5-88
Pages: 88
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Abstract

Abstract

Background

Complicated intra-abdominal infections (cIAI) remain challenging to treat because of their polymicrobial etiology including multi-drug resistant bacteria. The efficacy and safety of tigecycline, an expanded broad-spectrum glycylcycline antibiotic, was compared with imipenem/cilastatin (IMI/CIS) in patients with cIAI.

Methods

A prospective, double-blind, multinational trial was conducted in which patients with cIAI randomly received intravenous (IV) tigecycline (100 mg initial dose, then 50 mg every 12 hours [q12h]) or IV IMI/CIS (500/500 mg q6h or adjusted for renal dysfunction) for 5 to14 days. Clinical response at the test-of-cure (TOC) visit (14–35 days after therapy) for microbiologically evaluable (ME) and microbiological modified intent-to-treat (m-mITT) populations were the co-primary efficacy endpoint populations.

Results

A total of 825 patients received ≥ 1 dose of study drug. The primary diagnoses for the ME group were complicated appendicitis (59%), and intestinal (8.8%) and gastric/duodenal perforations (4.6%). For the ME group, clinical cure rates at TOC were 80.6% (199/247) for tigecycline versus 82.4% (210/255) for IMI/CIS (95% CI -8.4, 5.1 for non-inferiority tigecycline versus IMI/CIS). Corresponding clinical cure rates within the m-mITT population were 73.5% (227/309) for tigecycline versus 78.2% (244/312) for IMI/CIS (95% CI -11.0, 2.5). Nausea (31.0% tigecycline, 24.8% IMI/CIS [P = 0.052]), vomiting (25.7% tigecycline, 19.4% IMI/CIS [P = 0.037]), and diarrhea (21.3% tigecycline, 18.9% IMI/CIS [P = 0.435]) were the most frequently reported adverse events.

Conclusion

This study demonstrates that tigecycline is as efficacious as imipenem/cilastatin in the treatment of patients with cIAI.

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Article
The burden of diarrhoea, shigellosis, and cholera in North Jakarta, Indonesia: findings from 24 months surveillance

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Abstract

Abstract

Background

In preparation of vaccines trials to estimate protection against shigellosis and cholera we conducted a two-year community-based surveillance study in an impoverished area of North Jakarta which provided updated information on the disease burden in the area.

Methods

We conducted a two-year community-based surveillance study from August 2001 to July 2003 in an impoverished area of North Jakarta to assess the burden of diarrhoea, shigellosis, and cholera. At participating health care providers, a case report form was completed and stool sample collected from cases presenting with diarrhoea.

Results

Infants had the highest incidences of diarrhoea (759/1 000/year) and cholera (4/1 000/year). Diarrhea incidence was significantly higher in boys under 5 years (387/1 000/year) than girls under 5 years (309/1 000/year; p < 0.001). Children aged 1 to 2 years had the highest incidence of shigellosis (32/1 000/year). Shigella flexneri was the most common Shigella species isolated and 73% to 95% of these isolates were resistant to ampicillin, trimethoprim-sulfamethoxazole, chloramphenicol and tetracycline but remain susceptible to nalidixic acid, ciprofloxacin, and ceftriaxone. We found an overall incidence of cholera of 0.5/1 000/year. Cholera was most common in children, with the highest incidence at 4/1 000/year in those less than 1 year of age. Of the 154 V. cholerae O1 isolates, 89 (58%) were of the El Tor Ogawa serotype and 65 (42%) were El Tor Inaba. Thirty-four percent of patients with cholera were intravenously rehydrated and 22% required hospitalization. V. parahaemolyticus infections were detected sporadically but increased from July 2002 onwards.

Conclusion

Diarrhoea causes a heavy public health burden in Jakarta particularly in young children. The impact of shigellosis is exacerbated by the threat of antimicrobial resistance, whereas that of cholera is aggravated by its severe manifestations.

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Article
Cardiac involvement in a patient with clinical and serological evidence of African tick-bite fever

Authors: Bellini Cristina --- Monti Matteo --- Potin Mathieu --- Ave Anne --- et al.
DOI: 10.1186/1471-2334-5-90
Pages: 90
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Abstract

Abstract

Background

Myocarditis and pericarditis are rare complications of rickettsiosis, usually associated with Rickettsia rickettsii and R. conorii. African tick-bite fever (ATBF) is generally considered as a benign disease and no cases of myocardial involvement due to Rickettsia africae, the agent of ATBF, have yet been described.

Case presentation

The patient, that travelled in an endemic area, presented typical inoculation eschars, and a seroconversion against R. africae, was admitted for chest pains and increased cardiac enzymes in the context of an acute myocarditis.

Conclusion

Our findings suggest that ATBF, that usually presents a benign course, may be complicated by an acute myocarditis.

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Article
Systemic and local antibiotic prophylaxis in the prevention of Staphylococcus epidermidis graft infection

Authors: Turgut Huseyin --- Sacar Suzan --- Kaleli Ilknur --- Sacar Mustafa --- et al.
DOI: 10.1186/1471-2334-5-91
Pages: 91
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Abstract

Abstract

Background

The aim of the study was to investigate the in vivo efficacy of local and systemic antibiotic prophylaxis in the prevention of Staphylococcus (S.) epidermidis graft infection in a rat model and to evaluate the bacterial adherence to frequently used prosthetic graft materials.

Methods

Graft infections were established in the subcutaneous tissue of 120 male Wistar rats by implantation of Dacron/ePTFE grafts followed by topical inoculation with 2 × 107 CFUs of clinical isolate of methicillin-resistant S. epidermidis. Each of the graft series included a control group, one contaminated group that did not receive any antibiotic prophylaxis, two contaminated groups that received systemic prophylaxis with teicoplanin or levofloxacin and two contaminated groups that received teicoplanin-soaked or levofloxacin-soaked grafts. The grafts were removed 7 days after implantation and evaluated by quantitative culture.

Results

There was significant bacterial growth inhibition in the groups given systemic or local prophylaxis (P < 0.05). Methicillin-resistant S. epidermidis had greater affinity to Dacron graft when compared with ePTFE graft in the untreated contaminated groups (P < 0.05).

Conclusion

The study demonstrated that the usage of systemic or local prophylaxis and preference of ePTFE graft can be useful in reducing the risk of vascular graft infections caused by staphylococcal strains with high levels of resistance.

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Article
Pneumomediastinum as initial presentation of paralytic rabies: A case report

Authors: Kietdumrongwong Pongtorn --- Hemachudha Thiravat
DOI: 10.1186/1471-2334-5-92
Pages: 92
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Abstract

Abstract

Background

Rabies is readily diagnosed when it presents as the classic furious form. Paralytic and atypical forms can pose significant problems in diagnosis. Catastrophic incidents included 7 organ transplant recipients who died of rabies recently in United States and Germany. Although rabies remains top in the lists of differential diagnosis of encephalitis in rabies endemic area, its complication may divert physicians from making a relevant management. We encountered an unusual case of paralytic rabies who presented with spontaneous pneumomediastinum.

Case Presentation

A young male presented with fever and dysphagia. There was a history of fluctuating consciousness and aerophobia but they were absent or could not be demonstrated at the time of admission. He exhibited subcutaneous chest wall emphysema and was found to have pneumomediastinum which resulted in surgical intervention. He developed paralysis followed by seizures during postoperative period. Diagnosis was confirmed by demonstration of rabies RNA in saliva during the preterminal phase and by the autopsy. Over 200 hospital staff subsequently received rabies postexposure prophylaxis.

Conclusion

Spontaneous pneumomediastinum can be a rare complication of rabies. It may lead clinicians to perform inappropriate treatment, particularly when phobic spasms are not present and agitation is not prominent. High level of awareness of rabies in any patient with confusion albeit subtle or with any obscure neurological presentations such as difficulty swallowing with no identifiable causes must be borne in mind.

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Article
Clinical presentation and prognostic factors of Streptococcus pneumoniae meningitis according to the focus of infection

Authors: Østergaard Christian --- Konradsen Helle --- Samuelsson Susanne
DOI: 10.1186/1471-2334-5-93
Pages: 93
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Abstract

Abstract

Background

We conducted a nationwide study in Denmark to identify clinical features and prognostic factors in patients with Streptococcus pneumoniae according to the focus of infection.

Methods

Based on a nationwide registration, clinical information's was prospectively collected from all reported cases of pneumococcal meningitis during a 2-year period (1999–2000). Clinical and laboratory findings at admission, clinical course and outcome of the disease including follow-up audiological examinations were collected retrospectively. The focus of infection was determined according to the clinical diagnosis made by the physicians and after review of the medical records.

Results

187 consecutive cases with S. pneumoniae meningitis were included in the study. The most common focus was ear (30%), followed by lung (18%), sinus (8%), and other (2%). In 42% of cases a primary infection focus could not be determined. On admission, fever and an altered mental status were the most frequent findings (in 93% and 94% of cases, respectively), whereas back rigidity, headache and convulsion were found in 57%, 41% and 11% of cases, respectively. 21% of patients died during hospitalisation (adults: 27% vs. children: 2%, Fisher Exact Test, P < 0.001), and the causes of death were due to neurological – and systemic complications or the combination of both in 8%, 5% and 6% of cases, respectively. Other causes (e.g. gastrointestinal bleeding, incurable cancer) accounted for 2% of cases. 41% of survivors had neurological sequelae (hearing loss: 24%, focal neurological deficits: 16%, and the combination of both: 1%). The mortality varied with the focus of the infection (otogenic: 7%, sinusitic: 33%, pneumonic: 26%, other kind of focus: 50%, no primary infection focus: 21%, Log rank test: P = 0.0005). Prognostic factors associated with fatal outcome in univariate logistic regression analysis were advanced age, presence of an underlying disease, history of headache, presence of a lung focus, absence of an otogenic focus, having a CT-scan prior to lumbar puncture, convulsions, requirement of assisted ventilation, and alterations in various CSF parameters (WBC <500 cells/μL, high protein levels, glucose levels<1 mmol/L, low CSF/blood glucose levels), P < 0.05. Independent prognostic factor associated with fatal outcome in multivariate logistic regression analysis was convulsions (OR: 4.53, 95%CI: (1.74–11.8), p = 0.002), whereas presence of an otogenic focus was independently associated with a better survival (OR: 6.09, 95%CI: (1.75–21.2), P = 0.005).

Conclusion

These results emphasize the prognostic importance of an early recognition of a predisposing focus to pneumococcal meningitis.

Keywords


Article
Comparison of the systemic inflammatory response syndrome between monomicrobial and polymicrobial Pseudomonas aeruginosa nosocomial bloodstream infections

Authors: Marra Alexandre R --- Bearman Gonzalo ML --- Wenzel Richard P --- Edmond Michael B
DOI: 10.1186/1471-2334-5-94
Pages: 94
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Abstract

Abstract

Background

Some studies of nosocomial bloodstream infection (nBSI) have demonstrated a higher mortality for polymicrobial bacteremia when compared to monomicrobial nBSI. The purpose of this study was to compare differences in systemic inflammatory response and mortality between monomicrobial and polymicrobial nBSI with Pseudomonas aeruginosa.

Methods

We performed a historical cohort study on 98 adults with P. aeruginosa (Pa) nBSI. SIRS scores were determined 2 days prior to the first positive blood culture through 14 days afterwards. Monomicrobial (n = 77) and polymicrobial BSIs (n = 21) were compared.

Results

78.6% of BSIs were caused by monomicrobial P. aeruginosa infection (MPa) and 21.4% by polymicrobial P. aeruginosa infection (PPa). Median APACHE II score on the day of BSI was 22 for MPa and 23 for PPa BSIs. Septic shock occurred in 33.3% of PPa and in 39.0% of MPa (p = 0.64). Progression to septic shock was associated with death more frequently in PPa (OR 38.5, CI95 2.9–508.5) than MPa (OR 4.5, CI95 1.7–12.1). Maximal SIR (severe sepsis, septic shock or death) was seen on day 0 for PPa BSI vs. day 1 for MPa. No significant difference was noted in the incidence of organ failure, 7-day or overall mortality between the two groups. Univariate analysis revealed that APACHE II score ≥20 at BSI onset, Charlson weighted comorbidity index ≥3, burn injury and respiratory, cardiovascular, renal and hematologic failure were associated with death, while age, malignant disease, diabetes mellitus, hepatic failure, gastrointestinal complications, inappropriate antimicrobial therapy, infection with imipenem resistant P. aeruginosa and polymicrobial nBSI were not. Multivariate analysis revealed that hematologic failure (p < 0.001) and APACHE II score ≥20 at BSI onset (p = 0.005) independently predicted death.

Conclusion

In this historical cohort study of nBSI with P. aeruginosa, the incidence of septic shock and organ failure was high in both groups. Additionally, patients with PPa BSI were not more acutely ill, as judged by APACHE II score prior to blood culture positivity than those with MPa BSI. Using multivariable logistic regression analysis, the development of hematologic failure and APACHE II score ≥20 at BSI onset were independent predictors of death; however, PPa BSI was not.

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Article
Increased oxidative stress associated with the severity of the liver disease in various forms of hepatitis B virus infection

Authors: Bolukbas Cengiz --- Bolukbas Fusun --- Horoz Mehmet --- Aslan Mehmet --- et al.
DOI: 10.1186/1471-2334-5-95
Pages: 95
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Abstract

Abstract

Background

Oxidative stress can be defined as an increase in oxidants and/or a decrease in antioxidant capacity. There is limited information about the oxidative status in subjects with hepatitis B virus infection. We aimed to evaluate the oxidative status in patients with various clinical forms of chronic hepatitis B infection.

Methods

Seventy-six patients with hepatitis B virus infection, in whom 33 with chronic hepatitis, 31 inactive carriers and 12 with cirrhosis, and 16 healthy subjects were enrolled. Total antioxidant response and total peroxide level measurement, and calculation of oxidative stress index were performed in all participants.

Results

Total antioxidant response was significantly lower in cirrhotics than inactive HbsAg carriers and controls (p = 0.008 and p = 0.008, respectively). Total peroxide level and oxidative stress index was significantly higher in cirrhotic (p < 0.001, both) and chronic hepatitis B subjects (p < 0.001, both) than inactive HbsAg carriers and controls. Total antioxidant response was comparable in chronic hepatitis B subjects, inactive HbsAg carriers and controls (both, p > 0.05/6). Total peroxide level and oxidative stress index were also comparable in inactive HBsAg carriers and controls (both, p > 0.05/6). Serum alanine amino transferase level was positively correlated with total peroxide level and oxidative stress index only in chronic hepatitis B subjects (p = 0.002, r = 0.519 and p = 0.008, r = 0.453, respectively).

Conclusion

Oxidative stress occurs secondarily to increased total lipid peroxidation and inadequate total antioxidant response and is related to severity of the disease and replication status of virus in hepatitis B infection.

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Article
High carriage rate of high-level penicillin-resistant Streptococcus pneumoniae in a Taiwan kindergarten associated with a case of pneumococcal meningitis

Authors: Lauderdale Tsai-Ling --- Lee Wei --- Cheng Ming --- Huang I Fei --- et al.
DOI: 10.1186/1471-2334-5-96
Pages: 96
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Abstract

Abstract

Background

The Taiwan19F-14 Streptococcus pneumoniae clone and its variants are being found with increasing frequency in the Asia-Pacific region. A 5-year old child with S. pneumoniae meningitis caused by a high-level penicillin resistant strain (MIC = 4 μg/ml) was admitted to a hospital in southern Taiwan. We carried out a study to determine the potential source of this strain.

Methods

Nasopharyngeal cultures were obtained from all children attending the same kindergarten as the index case. To determine their relatedness all isolates were compared by serotype, antimicrobial susceptibility profile and pulsed field gel electrophoresis (PFGE).

Results

A high proportion of the children including the index case (32/78, 41.0%) carried S. pneumoniae in their nasopharynx (NP). The most common serotype was 19F (13/32, 40.6%). The PFGE types of the 19F serotype isolates obtained from the patient's blood, CSF and NP were identical and were related to 11 other serotype 19F NP isolates including 10 that were indistinguishable from the Taiwan19F-14 clone. All 14 isolates had similar high-level penicillin and multi-drug resistance. The serotypes of the other 19 NP isolates included 6A (2), 6B (10), 23F (5), 9V (1) and 3 (1). The overall rate of penicillin resistance in these S. pneumoniae from these children was 87.5% (28/32), with an MIC50 of 2 and MIC90 of 4 ug/ml. In addition, multi-drug resistant-isolates (isolates resistant to 3 different classes of antimicrobials) accounted for 87.5% (28/32) of all isolates.

Conclusion

The high carriage rate of high-level penicillin- and multi-drug- resistant S. pneumoniae in a kindergarten associated with a case of pneumococcal meningitis emphasizes the need for restraint in antibiotic use and consideration of childhood immunization with conjugate pneumococcal vaccine to prevent the further spread of resistant S. pneumoniae in Taiwan.

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Article
The changing epidemiology of pediatric aseptic meningitis in Daejeon, Korea from 1987 to 2003

Authors: Lee Kyung-Yil --- Burgner David --- Lee Hyung-Shin --- Hong Ja-Hyun --- et al.
DOI: 10.1186/1471-2334-5-97
Pages: 97
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Abstract

Abstract

Background

Aseptic meningitis is a relatively frequent childhood disease and virologic data suggest that enteroviruses are the commonest etiologic agents. We evaluated the epidemiologic characteristics of aseptic meningitis in Daejeon, South Korea from 1987 to 2003.

Methods

2201 medical records of children with aseptic meningitis admitted to The Catholic University of Korea, Daejeon St Mary's Hospital were retrospectively analyzed.

Results

Outbreaks of aseptic meningitis were observed in 1990, 1993, 1996, 1997, 2001 and 2002. The age distribution of cases was relatively uniform, with a higher incidence in those aged < 1 year and 4–7 years. The male-to-female ratio was 2:1. There was a higher incidence of disease in the summer (May to August, 74.1% of total). Comparison of the largest epidemics in 1997 and 2002 showed significant differences in the incidence in those < 1 year (11.8% vs. 4.4%, respectively; P = 0.001). Neurologic sequelae were observed in 0.7% of the patients.

Conclusion

Aseptic meningitis, rare before the 1980s in Korea, has since become a common clinical entity. Since 1990, outbreaks of aseptic meningitis have occurred every 1 to 3 years in Daejeon in keeping with Korea-wide epidemics. The frequency of disease affecting children less than one year of age may reflect herd immunity to the epidemic strain.

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Article
Cerebrospinal fluid HIV infection and pleocytosis: Relation to systemic infection and antiretroviral treatment

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Abstract

Abstract

Background

Central nervous system (CNS) exposure to HIV is a universal facet of systemic infection. Because of its proximity to and shared barriers with the brain, cerebrospinal fluid (CSF) provides a useful window into and model of human CNS HIV infection.

Methods

Prospective study of the relationships of CSF to plasma HIV RNA, and the effects of: 1) progression of systemic infection, 2) CSF white blood cell (WBC) count, 3) antiretroviral therapy (ART), and 4) neurological performance. One hundred HIV-infected subjects were cross-sectionally studied, and 28 were followed longitudinally after initiating or changing ART.

Results

In cross-sectional analysis, HIV RNA levels were lower in CSF than plasma (median difference 1.30 log10 copies/mL). CSF HIV viral loads (VLs) correlated strongly with plasma VLs and CSF WBC counts. Higher CSF WBC counts associated with smaller differences between plasma and CSF HIV VL. CSF VL did not correlate with blood CD4 count, but CD4 counts <50 cells/μL associated with a low prevalence of CSF pleocytosis and large differences between plasma and CSF VL. CSF HIV RNA correlated neither with the severity of the AIDS dementia complex (ADC) nor abnormal quantitative neurological performance, although these measures were associated with depression of CD4 counts.

In subjects starting ART, those with lower CD4 counts had slower initial viral decay in CSF than in plasma. In all subjects, including five with persistent plasma viremia and four with new-onset ADC, CSF HIV eventually approached or reached the limit of viral detection and CSF pleocytosis resolved.

Conclusion

CSF HIV infection is common across the spectrum of infection and is directly related to CSF pleocytosis, though whether the latter is a response to or a contributing cause of CSF infection remains uncertain. Slowing in the rate of CSF response to ART compared to plasma as CD4 counts decline indicates a changing character of CSF infection with systemic immunological progression. Longer-term responses indicate that CSF infection generally responds well to ART, even in the face of systemic virological failure due to drug resistance. We present simple models to explain the differing relationships of CSF to plasma HIV in these settings.

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Article
The trend of susceptibilities to amphotericin B and fluconazole of Candida species from 1999 to 2002 in Taiwan

Authors: Yang Yun-Liang --- Li Shu-Ying --- Cheng Hsiao-Hsu --- Lo Hsiu-Jung
DOI: 10.1186/1471-2334-5-99
Pages: 99
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Abstract

Abstract

Background

Candida species have various degrees of susceptibility to common antifungal drugs. The extent of resistance to amphotericin B and fluconazole of Candida glabrata isolates causing candidemia has been reported. Active surveillance may help us to monitor the trend of susceptibility to antifungal drugs and to determine if there is an emerging co-resistance to both drugs of Candida species, specifically, of C. glabrata in Taiwan.

Methods

The susceptibilities to amphotericin B and fluconazole of Candida species collected in 1999 and 2002 of the Taiwan Surveillance of Antimicrobial Resistance of Yeasts (TSARY) were determined by the microdilution method.

Results

The antifungal susceptibilities of 342 and 456 isolates collected from 11 hospitals participating in both TSARY 1999 and TSARY 2002, respectively, have been determined. The resistance rate to amphotericin B has increased from 0.3% in the TSARY1999 to 2.2% in the TSARY 2002. In contrast, the resistance rate to fluconazole has decreased from 8.8% to 2.2%. Nevertheless, significantly more C. glabrata isolates were not susceptible to fluconazole in the TSARY 2002 (47.4%) than that in the TSARY 1999 (20.8%). There were 9.8% and 11% of C. glabrata isolates having susceptible-dose dependent and resistant phenotype to fluconazole in the TSARY 1999, verse 45.3% and 2.1% in the TSARY 2002.

Conclusion

There was an increase of resistance rate to amphotericin B in C. glabrata. On the other hand, although the resistance rate to fluconazole has decreased, almost half of C. glabrata isolates were not susceptible to this drug. Hence, continuous monitoring the emerging of co-resistance to both amphotericin B and fluconazole of Candida species, specifically, of C. glabrata, will be an important early-warning system.

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Article
Epidural abscess caused by Streptococcus milleri in a pregnant woman

Authors: Lampen Russell --- Bearman Gonzalo
DOI: 10.1186/1471-2334-5-100
Pages: 100
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Abstract

Abstract

Background

Bacteria in the Streptococcus milleri group (S. anginosus, S. constellatus, and S. intermedius) are associated with bacteremia and abscess formation. While most reports of Streptococcus milleri group (SMG) infection occur in patients with underlying medical conditions, SMG infections during pregnancy have been documented. However, SMG infections in pregnant women are associated with either neonatal or maternal puerperal sepsis. Albeit rare, S. milleri spinal-epidural abscess in pregnancy has been reported, always as a complication of spinal-epidural anesthesia. We report a case of spinal-epidural abscess caused by SMG in a young, pregnant woman without an antecedent history of spinal epidural anesthesia and without any underlying risk factors for invasive streptococcal disease.

Case presentation

A 25 year old pregnant woman developed neurological symptoms consistent with spinal cord compression at 20 weeks gestation. She underwent emergency laminectomy for decompression and was treated with ceftriaxone 2 gm IV daily for 28 days. She was ambulatory at the time of discharge from the inpatient rehabilitation unit with residual lower extremity weakness.

Conclusion

To our knowledge, this is the first reported case of a Streptococcus milleri epidural abscess in a healthy, pregnant woman with no history of epidural anesthesia or invasive procedures. This report adds to the body of literature on SMG invasive infections. Treatment of SMG spinal-epidural abscess with neurologic manifestations should include prompt and aggressive surgical decompression coupled with targeted anti-infective therapy.

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Article
Adjunctive corticosteroids for Pneumocystis jiroveci pneumonia in patients with HIV infection: a meta-analysis of randomised controlled trials

Authors: Briel Matthias --- Boscacci Remy --- Furrer Hansjakob --- Bucher Heiner C
DOI: 10.1186/1471-2334-5-101
Pages: 101
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Abstract

Abstract

Background

The objective of this study was to review the effects of adjunctive corticosteroids on overall mortality and the need for mechanical ventilation in HIV-infected patients with Pneumocystis jiroveci pneumonia (PCP) and substantial hypoxemia (arterial oxygen partial pressure <70 mmHg or alveolar-arterial gradient >35 mmHg on room air).

Methods

We conducted a systematic search of the literature for randomised trials published up to December 2004. Selected trials compared adjunctive corticosteroids with placebo or usual care in HIV-infected patients with PCP and reported mortality data. Two teams of reviewers independently evaluated the methodology and extracted data from each primary study.

Results

Six studies were included in the meta-analysis. Risk ratios for overall mortality for adjunctive corticosteroids were 0.54 (95% confidence interval [CI], 0.38–0.79) at 1 month and 0.67 (95% CI, 0.49–0.93) at 3–4 months of follow-up. Numbers needed to treat, to prevent 1 death, are 9 patients in a setting without highly active antiretroviral therapy (HAART) available and 22 patients with HAART available. Only the 3 largest trials provided data on the need for mechanical ventilation with a risk ratio of 0.37 (95% CI, 0.20–0.70) in favour of adjunctive corticosteroids.

Conclusion

The number and size of trials investigating adjunctive corticosteroids for HIV-infected patients with PCP is small, but our results suggest a beneficial effect for patients with substantial hypoxemia.

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Article
Correlation between human papillomavirus infection and bladder transitional cell carcinoma

Authors: Barghi MR --- Hajimohammadmehdiarbab A --- Moghaddam SMM Hosseini --- Kazemi B
DOI: 10.1186/1471-2334-5-102
Pages: 102
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Abstract

Abstract

Background

To determine the association of human papillomavirus infection (HPV) and transitional cell carcinoma (TCC).

Methods

Using polymerase chain reaction, fifty-nine bladder tissue specimens of patients with transitional cell carcinoma of bladder compared with 20 bladder samples of cases with non-neoplastic disorders.

Results

Male to female ratio was similar in the two groups (50/9 vs. 16/4, P = 0.62). Mean age was 67 ± 10.8 years and 52 ± 20.3 years in the case and control groups, respectively (P = 0.6). Of the 59 tissue specimens with diagnosis of transitional cell carcinoma, HPV DNA was detected in 21 (35.6%) samples, while it was present in only one sample (5%) in the control group (P = 0.008). HPV18 was the most common type of virus with the incidence rate of 17/21(81%).

Conclusion

HPV might play a causative role in transitional cell carcinoma of bladder in our geographic area.

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Article
"Bacterial Meningitis in children and adolescents: an observational study based on the national surveillance system"

Authors: Dickinson Félix O --- Pérez Antonio E
DOI: 10.1186/1471-2334-5-103
Pages: 103
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Abstract

Abstract

Background

Bacterial meningitis is a group of life threatening infections that mostly affect children and adolescents, and may be the cause of severe neurological sequelae. Cuba has implemented massive vaccination programmes against both Neisseria meningitidis (serogroup C in 1979 and B in 1987), and Haemophilus influenzae type b (1999), two of the main causal pathogens. We described and discussed some epidemiological aspects of the current status of bacterial meningitis to learn from the Cuban experience.

Methods

A nationwide observational study on children and adolescents from 1 to 18 years old was carried out from 1998 to 2003, estimating the incidence and case-fatality rate by age group and causal pathogens, as well as the seasonality and frequency of overcrowded dormitories. The association between disease and attendance to day care centres or boarding schools was estimated by using relative risk (Chi-squared test and Fisher Exact Test).

Results

The overall number of cases was 1023; the incidence ranged from 3.4 to 8.5 per 100 000 population, with the higher figures in children 1–5 years old (16.8 per 100 000 population). Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis serogroup B were the main identified agents. The average case-fatality rate was 10.5% and the most lethal agents were Streptococcus pneumoniae (27%) and Haemophilus influenzae type b (10.7%). Overall percentage of cases who slept in overcrowded dormitories was 15%, reaching 30.6% in adolescents. Seasonality was only evident among meningococcal meningitis cases between September–October. The attendance to boarding high school showed an association with disease only in 1998 and 1999 (RR = 2.1; p > 0.05).

Conclusion

The highest incidence of bacterial meningitis was observed among children from 1–5 years old. Pneumococcus was both the leading causal and the most lethal agent. Sleeping in overcrowded dormitories was more frequent among adolescents. No strong association was observed between the bacterial meningitis and attendance to day care centres or boarding schools. The incidence of bacterial meningitis in Cuba is declining after massive vaccination programmes against Neisseria meningitidis serogroup B and C and Haemophilus influenzae type b through a national immunisation program.

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Article
Mechanisms of escape phenomenon of spinal cord and brainstem in human rabies

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Abstract

Abstract

Background

Rabies virus preferentially involves brainstem, thalamus and spinal cord in human furious and paralytic rabies beginning in the early stage of illness. Nevertheless, rabies patient remains alert until the pre-terminal phase. Weakness of extremities develops only when furious rabies patient becomes comatose; whereas peripheral nerve dysfunction is responsible for weakness in paralytic rabies.

Methods

Evidence of apoptosis and mitochondrial outer membrane permeabilization in brain and spinal cord of 10 rabies patients was examined and these findings were correlated with the presence of rabies virus antigen.

Results

Although apoptosis was evident in most of the regions, cytochrome c leakage was relatively absent in spinal cord of nearly all patients despite the abundant presence of rabies virus antigen. Such finding was also noted in brainstem of 5 patients.

Conclusion

Cell death in human rabies may be delayed in spinal cord and the reticular activating system, such as brainstem, thus explaining absence of weakness due to spinal cord dysfunction and preservation of consciousness.

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Article
Acquired homotypic and heterotypic immunity against oculogenital Chlamydia trachomatis serovars following female genital tract infection in mice

Authors: Lyons Joseph M --- Morré Servaas A --- Airo-Brown Lucy P --- Peña A Salvador --- et al.
DOI: 10.1186/1471-2334-5-105
Pages: 105
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Abstract

Abstract

Background

Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen causing female genital tract infection throughout the world. Reinfection with the same serovar, as well as multiple infections with different serovars, occurs in humans. Using a murine model of female C. trachomatis genital tract infection, we determined if homotypic and/or heterotypic protection against reinfection was induced following infection with human oculogenital strains of C. trachomatis belonging to two serovars (D and H) that have been shown to vary significantly in the course of infection in the murine model.

Methods

Groups of outbred CF-1 mice were reinfected intravaginally with a strain of either serovar D or H, two months after initial infection with these strains. Cellular immune and serologic status, both quantitative and qualitative, was assessed following initial infection, and the course of infection was monitored by culturing vaginal samples collected every 2–7 days following reinfection.

Results

Serovar D was both more virulent (longer duration of infection) and immunogenic (higher level of circulating and vaginal IgG and higher incidence of IgA in vaginal secretions) in the mouse genital tract. Although both serovars induced cross-reacting antibodies during the course of primary infection, prior infection with serovar H resulted in only a slight reduction in the median duration of infection against homotypic reinfection (p ~ 0.10), while prior infection with serovar D resulted in significant reduction in the median duration of infection against both homotypic (p < 0.01) and heterotypic reinfection (p < 0.01) when compared to primary infection in age and conditions matched controls.

Conclusion

Serovar D infection resulted in significant homotypic and heterotypic protection against reinfection, while primary infection with serovar H resulted in only slight homotypic protection. In addition to being the first demonstration of acquired heterotypic immunity between human oculogenital serovars, the differences in the level and extent of this immunity could in part explain the stable difference in serovar prevalence among human isolates.

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Article
Failure of levofloxacin treatment in community-acquired pneumococcal pneumonia

Authors: Endimiani Andrea --- Brigante Gioconda --- Bettaccini Alessia A --- Luzzaro Francesco --- et al.
DOI: 10.1186/1471-2334-5-106
Pages: 106
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Abstract

Abstract

Background

Streptococcus pneumoniae is the leading cause of community-acquired pneumonia (CAP). High global incidence of macrolide and penicillin resistance has been reported, whereas fluoroquinolone resistance is uncommon. Current guidelines for suspected CAP in patients with co-morbidity factors and recent antibiotic therapy recommend initial empiric therapy using one fluoroquinolone or one macrolide associated to other drugs (amoxicillin, amoxicillin/clavulanate, broad-spectrum cephalosporins). Resistance to fluoroquinolones is determined by efflux mechanisms and/or mutations in the parC and parE genes coding for topoisomerase IV and/or gyrA and gyrB genes coding for DNA gyrase. No clinical cases due to fluoroquinolone-resistant S. pneumoniae strains have been yet reported from Italy.

Case presentation

A 72-year-old patient with long history of chronic obstructive pulmonary disease and multiple fluoroquinolone treatments for recurrent lower respiratory tract infections developed fever, increased sputum production, and dyspnea. He was treated with oral levofloxacin (500 mg bid). Three days later, because of acute respiratory insufficiency, the patient was hospitalized. Levofloxacin treatment was supplemented with piperacillin/tazobactam. Microbiological tests detected a S. pneumoniae strain intermediate to penicillin (MIC, 1 mg/L) and resistant to macrolides (MIC >256 mg/L) and fluoroquinolones (MIC >32 mg/L). Point mutations were detected in gyrA (Ser81-Phe), parE (Ile460-Val), and parC gene (Ser79-Phe; Lys137-Asn). Complete clinical response followed treatment with piperacillin/tazobactam.

Conclusion

This is the first Italian case of community-acquired pneumonia due to a fluoroquinolone-resistant S. pneumoniae isolate where treatment failure of levofloxacin was documented. Molecular analysis showed a group of mutations that have not yet been reported from Italy and has been detected only twice in Europe. Treatment with piperacillin/tazobactam appears an effective means to inhibit fluoroquinolone-resistant strains of S. pneumoniae causing community-acquired pneumonia in seriously ill patients.

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Article
Catheter-associated bacteremia by Mycobacterium senegalense in Korea

Authors: Oh Won --- Ko Kwan --- Song Jae-Hoon --- Lee Mi --- et al.
DOI: 10.1186/1471-2334-5-107
Pages: 107
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Abstract

Abstract

Background

Rapidly growing mycobacteria is recognized as one of the causative agents of catheter-related infections, especially in immunocompromised hosts. To date, however, Mycobacterium senegalense, which was known as the principal pathogen of bovine farcy, has not been reported in human infection.

Case presentation

We describe the first case of human infection by M. senegalense, which has caused catheter-related bloodstream infection in a cancer patient in Korea. The microorganism was identified by the 16S rRNA gene, rpoB, and 16S-23S rRNA gene internal transcribed spacer (ITS) sequence analyses.

Conclusion

Our first report of catheter-associated bacteremia caused by M. senegalense suggests the zoonotic nature of this species and indicates the expansion of mycobacterial species relating to human infection. M. senegalense should be considered as one of the causes of human infections in the clinical practice.

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Article
High frequency of Human Cytomegalovirus DNA in the Liver of Infants with Extrahepatic Neonatal Cholestasis

Authors: De Tommaso Adriana MA --- Andrade Paula D --- Costa Sandra CB --- Escanhoela Cecília AF --- et al.
DOI: 10.1186/1471-2334-5-108
Pages: 108
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Abstract

Abstract

Background

Biliary atresia (BA) is the most severe hepatic disorder in newborns and its etiopathogenesis remains unknown. Viral involvement has been proposed, including the human cytomegalovirus (HCMV). The aims of the study were to use the polymerase chain reaction (PCR) to screen the liver tissue of infants with extrahepatic cholestasis for HCMV and to correlate the results with serological antibodies against HCMV and histological findings.

Methods

A retrospective study in a tertiary care setting included 35 patients (31 BA, 1 BA associated with a choledochal cyst, 2 congenital stenosis of the distal common bile duct and 1 hepatic cyst). HCMV serology was determined by ELISA. Liver and porta hepatis were examined histologically. Liver samples from infants and a control group were screened for HCMV DNA.

Results

Twelve patients had HCMV negative serology, 9 were positive for IgG antibodies and 14 were positive for IgG and IgM. Nine liver and seven porta hepatis samples were positive for HCMV DNA but none of the control group were positive (general frequency of positivity was 34.3% – 12/35). There was no correlation between HCMV positivity by PCR and the histological findings. The accuracy of serology for detecting HCMV antibodies was low.

Conclusion

These results indicate an elevated frequency of HCMV in pediatric patients with extrahepatic neonatal cholestasis. They also show the low accuracy of serological tests for detecting active HCMV infection and the lack of correlation between HCMV positivity by PCR and the histopathological changes.

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Article
Coxiella burnetii vascular graft infection

Authors: Senn Laurence --- Franciolli Mario --- Raoult Didier --- Moulin Alexandre --- et al.
DOI: 10.1186/1471-2334-5-109
Pages: 109
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Abstract

Abstract

Background

Coxiella burnetii, the causative agent of Q fever, may cause culture-negative vascular graft infections. Very few cases of C. burnetii infection of a vascular graft have been reported. All were diagnosed by serology.

Case presentation

We report the first case of Coxiella burnetii vascular graft infection diagnosed by broad-range PCR and discuss the diagnostic approaches and treatment strategies of chronic C. burnetii infection.

Conclusion

C. burnetii should be considered as etiological agent in patients with a vascular graft and fever, abdominal pain, and laboratory signs of inflammation, with or without exposure history. Broad-range PCR should be performed on culture-negative surgical samples in patients with suspected infection of vascular graft.

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Article
Bacterial isolates from blood cultures of children with suspected septicaemia in Calabar, Nigeria

Authors: Meremikwu Martin M --- Nwachukwu Chukwuemeka E --- Asuquo Anne E --- Okebe Joseph U --- et al.
DOI: 10.1186/1471-2334-5-110
Pages: 110
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Abstract

Abstract

Background

Septicaemia is a common cause of morbidity and mortality among children in the developing world. This pattern has changed little in the past decade. Physical signs and symptoms, though useful in identifying possible cases have limited specificity. Definitive diagnosis is by bacteriologic culture of blood samples to identify organisms and establish antibiotic susceptibility. These results are usually not available promptly. Therefore a knowledge of epidemiologic and antimicribial susceptibility pattern of common pathogens is useful for prompt treatment of patients. This report highlights the pattern of bacterial isolates in our environment from a retrospective study of our patients' records.

Methods

One thousand, two hundred and one blood samples were analysed from children aged 0–15 years, admitted into the children's wards of the University of Calabar Teaching Hospital, Calabar, Nigeria with features suggesting septicaemia. Samples were collected under aseptic conditions and cultured for aerobic and anaerobic organisms. Isolates were identified using bacteriologic and biochemical methods and antibiotic sensitivity determined by agar diffusion method using standard antibiotic discs.

Results

Bacteria was isolated in 552 (48.9%) of samples with highest rates among newborns (271 : 50.8). The most frequent isolates were Staphylococcal aureus (48.7%) and Coliforms (23.4%). Results showed high susceptibilities to the Cephalosporins (Ceftriazone- 100%:83.2%, Cefuroxime-100%:76.5%) and Macrolides (Azithromycin-100%:92.9%) for S. aureus and coliforms respectively. This study underscores the importance of septicaemia as a common cause of febrile illness in children and provides information on common prevalent aetiologic agents and drug susceptibilities of the commonest pathogens.

Conclusion

Staphylococcus aureus and coliforms were the leading causes of septicaemia in children in this locality, and the third generation cephalosporins and azithromycin were shown to be effective against these pathogens.

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Article
The role and performance of chest X-ray for the diagnosis of tuberculosis: A cost-effectiveness analysis in Nairobi, Kenya

Authors: van Cleeff MRA --- Kivihya-Ndugga LE --- Meme H --- Odhiambo JA --- et al.
DOI: 10.1186/1471-2334-5-111
Pages: 111
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Abstract

Abstract

Background

The objective of this study was to establish 1) the performance of chest X-ray (CXR) in all suspects of tuberculosis (TB), as well as smear-negative TB suspects and 2) to compare the cost-effectiveness of the routine diagnostic pathway using Ziehl-Neelsen (ZN) sputum microscopy followed by CXR if case of negative sputum result (ZN followed by CXR) with an alternative pathway using CXR as a screening tool (CXR followed by ZN).

Methods

From TB suspects attending a chest clinic in Nairobi, Kenya, three sputum specimens were examined for ZN and culture (Lowenstein Jensen). Culture was used as gold standard. From each suspect a CXR was made using a four point scoring system: i: no pathology, ii: pathology not consistent for TB, iii: pathology consistent for TB and iv: pathology highly consistent for TB. The combined score i + ii was labeled as "no TB" and the combined score iii + iv was labeled as "TB". Films were re-read by a reference radiologist. HIV test was performed on those who consented. Laboratory and CXR costs were used to compare for cost-effectiveness.

Results

Of the 1,389 suspects enrolled, for 998 (72%) data on smear, culture and CXR was complete. 714 films were re-read, showing a 89% agreement (kappa value = 0.75 s.e.0.037) for the combined scores "TB" or "no-TB". The sensitivity/specificity of the CXR score "TB" among smear-negative suspects was 80%/67%. Using chest CXR as a screening tool in all suspects, sensitivity/specificity of the score "any pathology" was 92%, respectively 63%. The cost per correctly diagnosed case was for the routine process $8.72, compared to $9.27 using CXR as screening tool. When costs of treatment were included, CXR followed by ZN became more cost-effective.

Conclusion

The diagnostic pathway ZN followed by CXR was more cost-effective as compared to CXR followed by ZN. When cost of treatment was also considered CXR followed by ZN became more cost-effective. The low specificity of chest X-ray remains a subject of concern. Depending whether CXR was performed on all suspects or on smear-negative suspects only, 22%–45% of patients labeled as "TB" had a negative culture. The introduction of a well-defined scoring system, clinical conferences and a system of CXR quality control can contribute to improved diagnostic performance.

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Article
Diagnostic and treatment delay among pulmonary tuberculosis patients in Ethiopia: a cross sectional study

Authors: Yimer Solomon --- Bjune Gunnar --- Alene Getu
DOI: 10.1186/1471-2334-5-112
Pages: 112
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Abstract

Abstract

Background

Delayed diagnosis and treatment of tuberculosis (TB) results in severe disease and a higher mortality. It also leads to an increased period of infectivity in the community. The objective of this study was to determine the length of delays, and analyze the factors affecting the delay from onset of symptoms of pulmonary tuberculosis (PTB) until the commencement of treatment.

Methods

In randomly selected TB management units (TBMUs), i.e. government health institutions which have diagnosing and treatment facilities for TB in Amhara Region, we conducted a cross sectional study from September 1-December 31/2003. Delay was analyzed from two perspectives, 1. Period between onset of TB symptoms to first visit to any health provider (health seeking period), and from the first health provider visit to initiation of treatment (health providers' delay), and 2. Period between onset of TB symptoms to first visit to a medical provider (patients' delay), and from this visit to commencement of anti-TB treatment (health systems' delay). Patients were interviewed on the same date of diagnosis using a semi-structured questionnaire. Logistics regression analysis was applied to analyze the risk factors of delays.

Results

A total of 384 new smear positive PTB patients participated in the study. The median total delay was 80 days. The median health-seeking period and health providers' delays were 15 and 61 days, respectively. Conversely, the median patients' and health systems' delays were 30 and 21 days, respectively. Taking medical providers as a reference point, we found that forty eight percent of the subjects delayed for more than one month. Patients' delays were strongly associated with first visit to non-formal health providers and self treatment (P < 0.0001). Prior attendance to a health post/clinic was associated with increased health systems' delay (p < 0.0001).

Conclusion

Delay in the diagnosis and treatment of PTB is unacceptably high in Amhara region. Health providers' and health systems' delays represent the major portion of the total delay. Accessing a simple and rapid diagnostic test for TB at the lowest level of health care facility and encouraging a dialogue among all health providers are imperative interventions.

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Article
Balance of IL-10 and Interferon-γ plasma levels in human visceral leishmaniasis: Implications in the pathogenesis

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Abstract

Abstract

Background

Leishmaniasis remains a serious public health problem in several parts of the developing world. Effective prophylactic measurements are hampered by imprecise comprehension of different aspects of the disease, including its immunoregulation. A better comprehension of immunoregulation in human VL may be useful both for designing and evaluating immunoprophylaxis.

Methods

To explore immunoregulatory mechanisms, 20 visceral leishmaniasis (VL) patients were evaluated during active disease and at different periods up to one year after treatment determining their plasma cytokine levels, clinical parameters (palpable spleen and liver) and antibody levels.

Results

Elevated plasma levels of IFN-γ and of IL-12 p40 were observed during active disease, significantly decreasing after treatment whereas in vitro Leishmania antigen-stimulated IFN-γ production by PBMC exhibited an inverse pattern being low during disease and increasing steadily thereafter. Absence of IFN-γ activity is a hallmark of VL. The main candidate for blunting IFN-γ activity is IL-10, a cytokine highly elevated in plasma with sharp decrease after treatment. Activity of IL-10 is inferred by high levels of anti-Leishmania specific IgG1 and IgG3. TGF-β had elevated total, but not of active, levels lessening the likelihood of being the IFN-γ counterpart. Spleen or liver size presented a steady decrease but return to normal values at only 120 days after treatment. Anti-Leishmania IgG (total and subclasses) levels and DTH or Leishmania-stimulated lymphocyte proliferation conversion to positive also present a slow decrease after treatment. IL-6 plasma levels were elevated in only a few patients.

Conclusion

Taken together our results suggest that IFN-γ and IL-10 are the molecules most likely involved in determining fate of disease. After treatment, there is a long delay before the immune profile returns to normal what precludes using plasma cytokine levels as criteria of cure as simpler clinical evaluations, as a palpable spleen or liver, can be used.

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Article
The CD14 functional gene polymorphism -260 C>T is not involved in either the susceptibility to Chlamydia trachomatis infection or the development of tubal pathology

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Abstract

Abstract

Background

The functional polymorphism -260 C>T in the LPS sensing TLR4 co-receptor CD14 gene enhances the transcriptional activity and results in a higher CD14 receptor density. Individuals carrying the T/T genotype also have significantly higher serum levels of soluble CD14. The T allele of this polymorphism has recently been linked to Chlamydia pneumoniae infection. We investigated the role of the CD14 -260 C>T polymorphism in the susceptibility to and severity (defined as subfertility and/or tubal pathology) of C. trachomatis infection in Dutch Caucasian women.

Methods

The different CD14 -260 C>T genotypes were assessed by PCR-based RFLP analysis in three cohorts: 1) A cohort (n = 576) of women attending a STD clinic, 2) a cohort (n = 253) of women with subfertility, and 3) an ethnically matched control cohort (n = 170). The following variables were used in the analysis: In cohort 1 the CT-DNA status, CT IgG serology status, self-reported symptoms and in cohort 2, the CT IgG serology status and the tubal status at laparoscopy.

Results

In the control cohort the CC, CT and TT genotype distribution was: 28.2%, 48.2%, and 23.5% respectively. No differences were found in the overall prevalence of CD14 -260 genotypes (28.1%, 50.7%, and 21.2%) in cohort 1 when compared to the control cohort. Also no differences were observed in women with or without CT-DNA, with or without serological CT responses, with or without symptoms, or in combinations of these three variables. In subfertile women with tubal pathology (cohort 2, n = 50) the genotype distribution was 28.0%, 48.0%, and 24.0% and in subfertile women without tubal pathology (n = 203), 27.6%, 49.3% and 23.2%. The genotype distribution was unchanged when CT IgG status was introduced in the analyses.

Conclusion

The CD14 -260 C>T genotype distributions were identical in all three cohorts, showing that this polymorphism is not involved in the susceptibility to or severity of sequelae of C. trachomatis infection.

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Article
A randomised controlled trial of the effects of albendazole in pregnancy on maternal responses to mycobacterial antigens and infant responses to bacille Calmette-Guérin (BCG) immunisation [ISRCTN32849447]

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Abstract

Abstract

Background

Maternal schistosomiasis and filariasis have been shown to influence infant responses to neonatal bacille Calmette-Guérin (BCG) immunisation but the effects of maternal hookworm, and of de-worming in pregnancy, are unknown.

Methods

In Entebbe, Uganda, we conducted a randomised, double-blind, placebo-controlled trial of a single dose of 400 mg of albendazole in the second trimester of pregnancy. Neonates received BCG. Interferon-gamma (IFN-γ) and interleukin (IL)-5 responses to a mycobacterial antigen (crude culture filtrate proteins (CFP) of Mycobacterium tuberculosis) were measured in a whole blood assay. We analysed results for binary variables using χ2 tests and logistic regression. We analysed continuous variables using Wilcoxon's tests.

Results

Maternal hookworm was associated with reduced maternal IFN-γ responses to CFP (adjusted odds ratio for IFN-γ > median response: 0.14 (95% confidence interval 0.02–0.83, p = 0.021). Conversely, maternal hookworm was associated with subsequent increased IFN-γ responses in their one-year-old infants (adjusted OR 17.65 (1.20–258.66; p = 0.013)). Maternal albendazole tended to reduce these effects.

Conclusion

Untreated hookworm infection in pregnancy was associated with reduced maternal IFN-γ responses to mycobacterial antigens, but increased responses in their infants one year after BCG immunisation. The mechanisms of these effects, and their implications for protective immunity remain, to be determined.

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Article
Prevalence and distribution of high-risk human papilloma virus (HPV) types in invasive squamous cell carcinoma of the cervix and in normal women in Andhra Pradesh, India

Authors: Sowjanya A Pavani --- Jain Meenkashi --- Poli Usha --- Padma S --- et al.
DOI: 10.1186/1471-2334-5-116
Pages: 116
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Abstract

Abstract

Background

Despite the high incidence of cervical cancer reported from India, large scale population based studies on the HPV prevalence and genotype distribution are very few from this region. In view of the clinical trials for HPV vaccine taking place in India, it is of utmost importance to understand the prevalence of HPV genotypes in various geographical regions of India. We investigated the genotype distribution of high-risk HPV types in squamous cell carcinomas and the prevalence of high-risk HPV in cervicovaginal samples in the southern state of Andhra Pradesh (AP), India.

Methods

HPV genotyping was done in cervical cancer specimens (n = 41) obtained from women attending a regional cancer hospital in Hyderabad. HPV-DNA testing was also done in cervicovaginal samples (n = 185) collected from women enrolled in the cervical cancer screening pilot study conducted in the rural community, of Medchal Mandal, twenty kilometers away from Hyderabad.

Results

High-risk HPV types were found in 87.8% (n = 36/41) of the squamous cell carcinomas using a PCR-based line blot assay. Among the HPV positive cancers, the overall type distribution of the major high-risk HPV types was as follows: HPV 16 (66.7%), HPV 18 (19.4%), HPV 33 (5.6%), HPV 35 (5.6%), HPV 45 (5.6%), HPV 52 (2.8%), HPV 58(2.8%), HPV 59(2.8%) and HPV 73 (2.8%). Women participating in the community screening programme provided both a self-collected vaginal swab and a clinician-collected cervical swab for HPV DNA testing. Primary screening for high risk HPV was performed using the Digene Hybrid Capture 2 (hc2) assay. All hc2 positive samples by any one method of collection were further analyzed using the Roche PCR-based line blot for genotype determination. The prevalence of high risk HPV infection in this community-based screening population was 10.3% (19/185) using the clinician-collected and 7.0% (13/185) using the self-collected samples. The overall agreement between self-collected and clinician-collected samples was 92%; however among HPV-positive specimens, the HPV agreement was only moderate (39.1%). The most frequently detected HPV types in the Medchal community are HPV 52 and 16.

Conclusion

Our results suggest that the HPV type distribution in both cervical cancer tissues and in a general screening population from Andhra Pradesh is similar to that reported in India and other parts of the world. We also conclude that an effective vaccine targeting HPV 16 will reduce the cervical cancer burden in AP.

Keywords

Table of content: 2005 volume:5 issue:1