Summary During the last decade, Clostridium difficile has emerged as a major cause of healthcare-associated diarrhoea and death. Transmission of this spore-forming bacterium is thought to occur via ...the hands of healthcare providers or via the contaminated environment. Therefore, enhanced environmental cleaning/disinfection of the rooms housing C. difficile -infected patients is warranted. Guidelines from various scientific bodies have been published. They recommend performing environmental decontamination of rooms of patients with C. difficile infection (CDI) using hypochlorite (diluted 1/10) or a sporicidal product. Compliance with cleaning and disinfection is a critical point and is often suboptimal. Novel ‘no-touch’ methods for room disinfection have recently been introduced. Ultraviolet (UV) light or hydrogen peroxide systems are most widely used. In-vitro studies suggest that hydrogen peroxide vapour (from 30% hydrogen peroxide) methods achieve a >6 log10 reduction in C. difficile spores placed on carriers, and that aerosolized hydrogen peroxide systems (from 5% to 6% hydrogen peroxide) achieve ∼4 log10 reduction, whereas UV-based methods achieve ∼2 log10 reduction. Very few studies have assessed the impact of these devices on the transmission of C. difficile . Major limitations of these devices include the fact that they can only be used after the patient's discharge, because patients and staff must be removed from the room. The new no-touch methods for room disinfection supplement, but do not replace, daily cleaning.
In 2009 the first European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guideline for diagnosing Clostridium difficile infection (CDI) was launched. Since then newer tests for ...diagnosing CDI have become available, especially nucleic acid amplification tests. The main objectives of this update of the guidance document are to summarize the currently available evidence concerning laboratory diagnosis of CDI and to formulate and revise recommendations to optimize CDI testing. This update is essential to improve the diagnosis of CDI and to improve uniformity in CDI diagnosis for surveillance purposes among Europe. An electronic search for literature concerning the laboratory diagnosis of CDI was performed. Studies evaluating a commercial laboratory test compared to a reference test were also included in a meta-analysis. The commercial tests that were evaluated included enzyme immunoassays (EIAs) detecting glutamate dehydrogenase, EIAs detecting toxins A and B and nucleic acid amplification tests. Recommendations were formulated by an executive committee, and the strength of recommendations and quality of evidence were graded using the Grades of Recommendation Assessment, Development and Evaluation (GRADE) system. No single commercial test can be used as a stand-alone test for diagnosing CDI as a result of inadequate positive predictive values at low CDI prevalence. Therefore, the use of a two-step algorithm is recommended. Samples without free toxin detected by toxins A and B EIA but with positive glutamate dehydrogenase EIA, nucleic acid amplification test or toxigenic culture results need clinical evaluation to discern CDI from asymptomatic carriage.
Clostridium difficile is recognized as the major agent responsible for nosocomial diarrhoea. In the context of recent increase in the incidence and severity of C. difficile infections (CDI), an ...accurate diagnosis is essential for optimal treatment and prevention, but continues to be challenging.
The present article reviews each key step of CDI diagnosis including stool selection, methods and strategies used, and interpretation of the results.
The most recent guidelines for CDI diagnosis published by scientific societies were reviewed.
CDI diagnosis is based on clinical presentation and laboratory tests confirming the presence of toxigenic strain or toxins in stools. Stool selection is crucial and can be improved by implementing rejection criteria and a strict policy for appropriate testing. Multiple laboratory tests detecting different targets (free toxin or presence of a potentially toxigenic strain) are commercially available. However, none of these tests combine high sensitivity and specificity to diagnose CDI, low hands-on time and low cost. An optimized diagnosis can be achieved by implementing a two- or three-step algorithm. Algorithms currently recommended by the ESCMID comprise a screening test with high sensitivity followed by a more specific test to detect free toxins. Presence of free toxins in stools has been shown to better correlate with severe outcome whereas nucleic acid amplification tests may lead to an over-diagnosis by detecting asymptomatic carriers of a toxigenic strain.
To date, no single test can accurately diagnose CDI. Guidelines from the ESCMID recommend a two- or three-step algorithm for optimal CDI detection.
Clostridium difficile infection (CDI) is the most important infective cause of healthcare-associated diarrhoea in high income countries and one of the most important healthcare-associated pathogens ...in both Europe and the United States. It is associated with high morbidity and mortality resulting in both societal and financial burden. A significant proportion of this burden is potentially preventable by a combination of targeted infection prevention and control measures and antimicrobial stewardship. The aim of this guidance document is to provide an update on recommendations for prevention of CDI in acute care settings to provide guidance to those responsible for institutional infection prevention and control programmes.
An expert group was set up by the European society of clinical microbiology and infectious diseases (ESCMID) Study Group for C. difficile (ESGCD), which performed a systematic review of the literature on prevention of CDI in adults hospitalized in acute care settings and derived respective recommendations according to the GRADE approach. Recommendations are stratified for both outbreak and endemic settings.
This guidance document provides thirty-six statements on strategies to prevent CDI in acute care settings, including 18 strong recommendations. No recommendation was provided for three questions.
To compare a hydrogen peroxide dry-mist system and a 0.5% hypochlorite solution with respect to their ability to disinfect Clostridium difficile-contaminated surfaces in vitro and in situ.
...Prospective, randomized, before-after trial.
Two French hospitals affected by C. difficile.
In situ efficacy of disinfectants was assessed in rooms that had housed patients with C. difficile infection. A prospective study was performed at 2 hospitals that involved randomization of disinfection processes. When a patient with C. difficile infection was discharged, environmental contamination in the patient's room was evaluated before and after disinfection. Environmental surfaces were sampled for C. difficile by use of moistened swabs; swab samples were cultured on selective plates and in broth. Both disinfectants were tested in vitro with a spore-carrier test; in this test, 2 types of material, vinyl polychloride (representative of the room's floor) and laminate (representative of the room's furniture), were experimentally contaminated with spores from 3 C. difficile strains, including the epidemic clone ribotype 027-North American pulsed-field gel electrophoresis type 1.
There were 748 surface samples collected (360 from rooms treated with hydrogen peroxide and 388 from rooms treated with hypochlorite). Before disinfection, 46 (24%) of 194 samples obtained in the rooms randomized to hypochlorite treatment and 34 (19%) of 180 samples obtained in the rooms randomized to hydrogen peroxide treatment showed environmental contamination. After disinfection, 23 (12%) of 194 samples from hypochlorite-treated rooms and 4 (2%) of 180 samples from hydrogen peroxide treated rooms showed environmental contamination, a decrease in contamination of 50% after hypochlorite decontamination and 91% after hydrogen peroxide decontamination (P < .005). The in vitro activity of 0.5% hypochlorite was time dependent. The mean (+/-SD) reduction in initial log(10) bacterial count was 4.32 +/- 0.35 log(10) colony-forming units after 10 minutes of exposure to hypochlorite and 4.18 +/- 0.8 log(10) colony-forming units after 1 cycle of hydrogen peroxide decontamination.
In situ experiments indicate that the hydrogen peroxide dry-mist disinfection system is significantly more effective than 0.5% sodium hypochlorite solution at eradicating C. difficile spores and might represent a new alternative for disinfecting the rooms of patients with C. difficile infection.
The European, multicentre, quarterly point-prevalence study of community-acquired diarrhoea (EUCODI) analysed stool samples received at ten participating clinical microbiology laboratories (Austria, ...Finland, France, Germany, Greece, Ireland, Italy, Portugal, Romania, and the UK) in 2014. On four specified days, each local laboratory submitted samples from ≤20 consecutive patients to the Austrian Study Centre for further testing with the FilmArray GI Panel (BioFire Diagnostics, Salt Lake City, UT, USA). Of the 709 samples from as many patients received, 325 (45.8%) tested negative, 268 (37.8%) yielded only one organism, and 116 (16.4%) yielded multiple organisms. Positivity rates ranged from 41% (30 of 73 samples) in France to 74% (59 of 80 samples) in Romania. With the exception of Entamoeba histolytica and Vibrio cholerae, all of the 22 targeted pathogens were detected at least once. Enteropathogenic Escherichia coli, Campylobacter species, toxigenic Clostridium difficile, enteroaggregative E. coli, norovirus and enterotoxigenic E. coli were the six most commonly detected pathogens. When tested according to local protocols, seven of 128 positive samples (5.5%) yielded multiple organisms. Overall, the FilmArray GI Panel detected at least one organism in 54.2% (384/709) of the samples, as compared with 18.1% (128/709) when testing was performed with conventional techniques locally. This underlines the considerable potential of multiplex PCR to improve routine stool diagnostics in community-acquired diarrhoea. Classic culture methods directed at the isolation of specific pathogens are increasingly becoming second-line tools, being deployed when rapid molecular tests give positive results. This optimizes the yield from stool examinations and dramatically improves the timeliness of diagnosis.
Reported rates of community-acquired Clostridium difficile infections (CDIs) have been increasing. However, the true burden of the disease in general practice is unknown in France. Our objective was ...to determine the incidence of toxigenic C. difficile carriage and the percentage of stool samples prescribed by general practitioners (GPs) which contained free C. difficile toxins.
During an 11-month period, all stool samples submitted for any enteric pathogen detection to 15 different private laboratories in Paris and the surrounding areas were tested for C. difficile, irrespective of the GPs' request. A clinical questionnaire was completed for each patient. Stool samples were screened using a rapid simultaneous glutamate dehydrogenase and toxins A/B detection test: any positive result (glutamate dehydrogenase or toxin) was further confirmed by the stool cytotoxicity assay (CTA) on MRC-5 cells and by toxigenic culture (TC) at a central laboratory. The C. difficile isolates were characterized by PCR ribotyping.
A total of 2541 patients (1295 female, 1246 male) were included. The incidences of patients with a positive toxigenic culture and a positive CTA were 3.27% (95% CI 2.61%–4.03%) and 1.81% (95% CI 1.33%–2.41%), respectively. GPs requested C. difficile testing in only 12.93% of the stool samples, detecting 52.30% of all TC-positive patients. The 83 toxigenic C. difficile strains belonged to 36 different PCR ribotypes.
Toxigenic C. difficile carriage is frequent in general practice but remains under-recognized. It may affect young patients without previous antimicrobial therapy or hospitalization.
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