Prolonged oral vancomycin for secondary prophylaxis of relapsing Clostridium difficile infectionBMC Infectious Diseases - Tập 19 - Trang 1-4 - 2019
Kevin Zhang, Patricia Beckett, Salaheddin Abouanaser, Vida Stankus, Christine Lee, Marek Smieja
Clostridium difficile infection (CDI) is an important cause of diarrhea and continues to be a major burden within healthcare institutions and in the community. For a small subset of patients with frequently relapsing CDI who do not have access to fecal microbiota transplantation (FMT), or fail FMT, there are no clear treatment recommendations. We review our experience with prolonged oral vancomycin for secondary prophylaxis of relapsing CDI. We performed a retrospective chart review of cases from the C. difficile consultation service at our institution since 2013. The service had three primary physicians providing consultations and performing over 1000 FMTs over the five-year period. Patients with relapsing CDI who were not candidates for FMT, refused, or relapsed after FMT were treated with vancomycin, followed by long-term oral vancomycin at a dose of 125 mg once daily. Twenty patients received at least 8 weeks of once-daily oral vancomycin for prophylaxis of relapsing CDI. Patients had a median age of 80 years, and experienced a median of four episodes of CDI prior to long-term vancomycin. Most were female and 75% had received FMT. Only a single case of C. difficile relapse occurred while on long-term vancomycin during 200 patient-months of follow-up. Amongst those who stopped long-term vancomycin, 31% relapsed within 6 weeks. No adverse events were observed. For elderly patients with frequently relapsing C. difficile, prolonged vancomycin once daily at a dose of 125 mg orally was effective in preventing further relapse. Vancomycin secondary prophylaxis may be considered in patients who have failed FMT, or in cases where FMT is not available.
Field test of a novel detection device for Mycobacterium tuberculosis antigen in coughBMC Infectious Diseases - Tập 10 - Trang 1-6 - 2010
Ruth McNerney, Beyene A Wondafrash, Kebede Amena, Ato Tesfaye, Elaine M McCash, Nicol J Murray
Tuberculosis is a highly infectious disease that is spread from person to person by infected aerosols emitted by patients with respiratory forms of the disease. We describe a novel device that utilizes immunosensor and bio-optical technology to detect M. tuberculosis antigen (Ag85B) in cough and demonstrate its use under field conditions during a pilot study in an area of high TB incidence. The TB Breathalyzer device (Rapid Biosensor Systems Ltd) was field tested in the outpatient clinic of Adama Hospital, Ethiopia. Adults seeking diagnosis for respiratory complaints were tested. Following nebulization with 0.9% saline patients were asked to cough into a disposable collection device where cough aerosols were deposited. Devices were then inserted into a portable instrument to assess whether antigen was present in the sample. Demographic and clinical data were recorded and all patients were subjected to chest radiogram and examination of sputum by Ziehl-Nielsen microscopy. In the absence of culture treatment decisions were based on smear microscopy, chest x-ray and clinical assessment. Breathalyzer testing was undertaken by a separate physician to triage and diagnostic assessment. Sixty individuals were each subjected to a breathalyzer test. The procedure was well tolerated and for each patient the testing was completed in less than 10 min. Positive breath test results were recorded for 29 (48%) patients. Of 31 patients with a diagnosis of tuberculosis 23 (74%; 95% CI 55-87) were found positive for antigen in their breath and 20 (64%; 95% CI 45-80) were smear positive for acid fast bacilli in their sputum. Six patients provided apparent false positive breathalyzer results that did not correlate with a diagnosis of tuberculosis. We propose that the breathalyzer device described warrants further investigation as a tool for studying exhalation of M. tuberculosis. The portability, simplicity of use and speed of the test device suggest it may also find use as a tool to aid early identification of infectious cases. We recommend studies be undertaken to determine the diagnostic sensitivity and specificity of the device when compared to microbiological and clinical indicators of tuberculosis disease.
Genetic relatedness among isolates of Shigella sonnei carrying class 2 integrons in Tehran, Iran, 2002–2003BMC Infectious Diseases - Tập 7 Số 1 - 2007
Reza Ranjbar, Aurora Aléo, Anna Giammanco, Anna Maria Dionisi, Nourkhoda Sadeghifard, Caterina Mammina
Abstract
Background
Shigella spp. are major cause of diarrhoeal disease in both developing and developed countries. Shigella sonnei is the serogroup of Shigella most frequently responsible for sporadic and epidemic enteritis in developed countries. In recent years the emergence and spread of S. sonnei biotype g carrying class 2 integron have been frequently reported in many countries. Recently, S. sonnei has been reported as the prevalent serogroup of Shigella in Iran.
The present study was carried out to investigate phenotypic and genetic characteristics of Shigella sonnei isolates identified in the years 2002 and 2003 in Tehran, Iran.
Methods
Biotyping, drug susceptibility testing, pulsed field gel electrophoresis (PFGE) and analysis of class 2 integrons have been carried out on 60 S. sonnei isolates, including 57 sporadic isolates from paediatric cases of shigellosis occurring in 2002 and 2003, two sporadic isolates recovered in 1984 and the ATCC 9290 strain.
Results
Biotype g and resistance to streptomycin, sulfamethoxazole-trimethoprim and tetracycline were exhibited by 54 of the 57 recent isolates. Of the 54 biotype g isolates, 28 exhibited a class 2 integron of 2161 bp, and 24 a class 2 integron of 1371 bp, respectively. Class 2 integrons were not detected in four isolates only, including the two endemic isolates recovered in 1984 and two strains from recent sporadic cases. PFGE divided the strains into eight pulsotypes labeled A to H, three major pulsotypes – A to C – including the large majority of the recent sporadic S. sonnei isolates. Pulsotypes A and C were the most prevalent groups, accounting for 41.6% and 35.0%, respectively, of the isolates under study.
Conclusion
The results suggest that biotype g, class 2 integron carrying S. sonnei are prevalent in our geographic area. S. sonnei isolated in the years 2002 and 2003 could be attributed to a few predominant clusters including, respectively, strains with pulsotypes B and C carrying a 2161 bp class 2 integron, and those having pulsotype A and a 1371 bp class 2 integron. A few epidemic clones are responsible for the apparently endemic occurrence of shigellosis in Tehran, Iran.
Dermatophyte abscesses caused by Trichophyton rubrum in a patient without pre-existing superficial dermatophytosis: a case reportBMC Infectious Diseases - Tập 16 - Trang 1-5 - 2016
Si-Hyun Kim, Ik Hyun Jo, Jun Kang, Sun Young Joo, Jung-Hyun Choi
Trichophyton usually causes a superficial skin infection, affecting the outermost layer of the epidermis, the stratum corneum. In immunocompromised patients, deeper invasion into the dermis and even severe systemic infection with distant organ involvement can occur. Most cases of deeper dermal dermatophytosis described in the literature so far involved pre-existing superficial dermatophytosis. We report a 68-year-old woman presented to our clinic with a 3-month history of palpable nodules on the right ankle without pre-existing superficial dermatophytosis. Magnetic resonance imaging showed multiple, well-demarcated, cystic lesions around the lateral malleolus, located in the subcutaneous or dermal layers. The sizes varied from 0.5 cm to 4 cm in diameter. The patient underwent complete excision of the lesions. Fungal culture yielded Trichophyton rubrum on Sabouraud dextrose agar. Histopathology showed organizing abscesses with degenerated fungal hyphae. After the 12-week oral itraconazole therapy, the lesions were completely resolved. Dermatophytes should be considered as a possible cause of deep soft tissue abscesses in immunocompromised patients, even though there is no superficial dermatophytosis lesion.
The impact of the COVID-19 pandemic on patients’ experiences obtaining a tuberculosis diagnosis in Peru: a mixed-methods studyBMC Infectious Diseases - Tập 22 - Trang 1-7 - 2022
Ana Karina Millones, Leonid Lecca, Diana Acosta, Hortencia Campos, Erika Del Águila-Rojas, Sheyla Farroñay, Giannina Morales, Judith Ramirez-Sandoval, Isabel Torres, Judith Jimenez, Courtney M. Yuen
The COVID-19 pandemic disrupted TB services worldwide, leading to diagnostic delays. There have been few published reports describing how the pandemic affected people’s pathway to diagnosis from their own perspectives. We sought to evaluate the impact on the pandemic on people’s experiences obtaining a TB diagnosis. We performed a mixed-methods study, enrolling newly diagnosed TB patients from 12 health centers in Lima, Peru. We used structured surveys to quantify diagnostic delay, defined as the time between symptom onset and diagnosis, and in-depth interviews to understand the ways in which the pandemic affected the pathway to care. We compared diagnostic delay between patients enrolled during the first year of the pandemic to those diagnosed after using a Wilcoxon rank-sum test. We used an inductive content analysis approach to analyze interview content related to the pandemic. We enrolled 51 patients during November 2020–April 2021 (during the first year of the pandemic) and 49 patients during October 2021–February 2022. Median diagnostic delay was longer for patients diagnosed during the first year of the pandemic (median 15 [IQR 5–26] weeks compared to 6 [IQR 3–18] weeks, p = 0.027). Qualitative analysis of 26 interviews revealed that the pandemic affected participants’ care-seeking behavior and their ability to access to TB diagnostic services, particularly for those diagnosed in the first year of the pandemic. Many participants initially had their symptoms attributed to COVID-19, resulting in delayed TB evaluation and additional costs for COVID-19 treatment. The COVID-19 pandemic impacted multiple steps in the pathway to care for TB patients in Lima, causing delays in TB diagnosis. These findings demonstrate how the shifting of health care resources to prioritize COVID-19 can lead to collateral damage for people with TB and other conditions.
Comparison of two dengue NS1 rapid tests for sensitivity, specificity and relationship to viraemia and antibody responsesBMC Infectious Diseases - Tập 10 - Trang 1-8 - 2010
Vianney Tricou, Hang TT Vu, Nhu VN Quynh, Chau VV Nguyen, Hien T Tran, Jeremy Farrar, Bridget Wills, Cameron P Simmons
Dengue is a major public health problem in tropical and subtropical countries. Rapid and easy diagnosis of dengue can assist patient triage and care-management. The detection of DENV NS1 on rapid lateral flow tests offers a fast route to a presumptive dengue diagnosis but careful evaluations are urgently needed as more and more people use them. The sensitivity and specificity of the Bio-Rad NS1 Ag Strip and SD Dengue Duo (NS1/IgM/IgG) lateral flow rapid tests were evaluated in a panel of plasma samples from 245 Vietnamese patients with RT-PCR confirmed dengue and 47 with other febrile illnesses. The NS1 rapid tests had similar diagnostic sensitivities (respectively 61.6% and 62.4%) in confirmed dengue cases but were 100% specific. When IgM/IgG results from the SD Dengue Duo were included in the test interpretation, the sensitivity improved significantly from 62.4% with NS1 alone to 75.5% when NS1 and/or IgM was positive and 83.7% when NS1 and/or IgM and/or IgG was positive. Both NS1 assays were significantly more sensitive for primary than secondary dengue. NS1 positivity was associated with the underlying viraemia as NS1-positive samples had a significantly higher viraemia than NS1-negative samples. These data suggest that the NS1 test component of these assays are highly specific and have similar levels of sensitivity. The IgM parameter in the SD Duo test improved overall test sensitivity without compromising specificity. The SD Dengue Duo lateral flow rapid test deserves further prospective evaluation in dengue endemic settings.
Syphilis reinfection is associated with an attenuated immune profile in the same individual: a prospective observational cohort studyBMC Infectious Diseases - Tập 18 - Trang 1-7 - 2018
Chris Kenyon, Kara Krista Osbak, Tania Crucitti, Luc Kestens
Ascertaining if the clinical and immunological response to repeat syphilis differs from that in initial syphilis may assist in designing optimal syphilis screening strategies and vaccine design. We prospectively recruited 120 patients with a new diagnosis of (baseline) syphilis. During a 24-month follow-up period, 11 of these patients had a further diagnosis of (repeat) syphilis. We conducted a paired comparison of their plasma cyto-chemokines at baseline and repeat syphilis. Comparing to their baseline infection, paired analyses of the 11 individuals with repeat infections during follow-up revealed that these reinfections had lower concentrations of Interferon (IFN)α (0.8 [Interquartile range (IQR) 0.8–0.8 vs. 12.2 [IQR 1.6–24.2], P = 0.004) and Chemokine (C-C motif) ligand (CCL) 4 (0.9 [IQR 0.9–12.2 vs. 17.5 [IQR 4.9–32.8], P = 0.022]. In this small study of 11 individuals, repeat syphilis was found to present with an attenuated immune response. The relevance of these findings to the design of optimal syphilis screening programs is discussed.
Estimating the under-reporting of norovirus illness in Germany utilizing enhanced awareness of diarrhoea during a large outbreak of Shiga toxin-producing E. coli O104:H4 in 2011 – a time series analysisBMC Infectious Diseases - Tập 14 - Trang 1-6 - 2014
Helen Bernard, Dirk Werber, Michael Höhle
Laboratory-confirmed norovirus illness is reportable in Germany since 2001. Reported case numbers are known to be undercounts, and a valid estimate of the actual incidence in Germany does not exist. An increase of reported norovirus illness was observed simultaneously to a large outbreak of Shiga toxin-producing E. coli O104:H4 in Germany in 2011 – likely due to enhanced (but not complete) awareness of diarrhoea at that time. We aimed at estimating age- and sex-specific factors of that excess, which should be interpretable as (minimal) under-reporting factors of norovirus illness in Germany. We used national reporting data on laboratory-confirmed norovirus illness in Germany from calendar week 31 in 2003 through calendar week 30 in 2012. A negative binomial time series regression model was used to describe the weekly counts in 8∙2 age-sex strata while adjusting for secular trend and seasonality. Overall as well as age- and sex-specific factors for the excess were estimated by including additional terms (either an O104:H4 outbreak period indicator or a triple interaction term between outbreak period, age and sex) in the model. We estimated the overall under-reporting factor to be 1.76 (95% CI 1.28-2.41) for the first three weeks of the outbreak before the outbreak vehicle was publicly communicated. Highest under-reporting factors were here estimated for 20–29 year-old males (2.88, 95% CI 2.01-4.11) and females (2.67, 95% CI 1.87-3.79). Under-reporting was substantially lower in persons aged <10 years and 70 years or older. These are the first estimates of (minimal) under-reporting factors for norovirus illness in Germany. They provide a starting point for a more detailed investigation of the relationship between actual incidence and reporting incidence of norovirus illness in Germany.
Specific detection of H5N1 avian influenza A virus in field specimens by a one-step RT-PCR assayBMC Infectious Diseases - - 2006
Lisa F. P. Ng, Ian Barr, Tung Nguyen, Suriani Mohd Noor, Rosemary Tan, Lora V. Agathe, Sanjay Gupta, Hassuzana Khalil, Thanh Long To, Sharifah Syed Hassan, Ee Chee Ren
Abstract
Background
Continuous outbreaks of the highly pathogenic H5N1 avian influenza A in Asia has resulted in an urgent effort to improve current diagnostics to aid containment of the virus and lower the threat of a influenza pandemic. We report here the development of a PCR-based assay that is highly specific for the H5N1 avian influenza A virus.
Methods
A one-step reverse-transcription PCR assay was developed to detect the H5N1 avian influenza A virus. The specificity of the assay was shown by testing sub-types of influenza A virus and other viral and bacterial pathogens; and on field samples.
Results
Validation on 145 field specimens from Vietnam and Malaysia showed that the assay was specific without cross reactivity to a number of other infuenza strains as well as human respiratory related pathogens. Detection was 100% from allantoic fluid in H5N1 positive samples, suggesting it to be a reliable sampling source for accurate detection.
Conclusion
The assay developed from this study indicates that the primers are specific for the H5N1 influenza virus. As shown by the field tested results, this assay would be highly useful as a diagnostic tool to help identify and control influenza epidemics.
