Diagnosis Of Clostridium Difficile-associated Diarrhea Research Articles

Risk Factors Associated With Clostridium difficile-Associated Diarrhea.

Introduction: Recent years have been alarming due to the sudden, dramatic rise in the incidence of Clostridium difficile infection (CDI). Identifying and addressing the risk factors associated with CDI will help in reducing the incidence of infection and associated complications.Methods: This case-control study was conducted in a tertiary care hospital in Pakistan from June 2020 to March 2021, in which 200 patients diagnosed with Clostridium difficile-associated diarrhea (CDAD) were enrolled in the study. CDAD was diagnosed based on clinical symptoms and stool enzyme immunoassay. Another 200 participants without a diagnosis of CDAD were enrolled from the outpatient department as a control group. Participants were enrolled after seeking informed consent.Results: In patients older than 65, risk of CDI was higher compared to participants lower than 65 years old (15.5% vs. 8.0%; p value: 0.02). Hospitalization (25.5% vs. 6.0%; p value < 0.0001), the use of proton pump inhibitors in last 30 days (23.0% vs. 10.5%; p value: 0.001) , and use of antibiotics in the last 30 days (36.0% vs. 10.5%; p value < 0.0001) were significantly higher in participants with CDI.Conclusion: Hospitalization, the usage of proton pump inhibitors, and antibiotics in the last 30 days were significantly associated with CDI. A higher incidence of CDI was associated with risk factors like increased body mass index, diabetes, chronic kidney disease, and malignancy.

Laboratory experience with the liaison analyzer in the diagnosis of Clostridium difficile-associated diarrhea

BackgroundChemiluminescent or enzyme-linked fluorescent immunoassays are commonly used to diagnose Clostridium difficile-associated diarrhea.MethodsThe LIAISON analyzer (DiaSorin, Italy) was compared to miniVIDAS (bioMérieux, France) and, furthermore, to culture of toxigenic strains. In total, 249 native stool samples were analyzed. Sensitivities, specificities, and positive and negative predictive values were investigated. Furthermore, performance under routine conditions was assessed.ResultsThe glutamate dehydrogenase chemiluminescent immunoassay (GDH-CLIA) assay revealed a high sensitivity and negative predictive value. The toxins A&B assays exhibited approximately the same low sensitivity and high specificity. Technical drawbacks experienced with the LIAISON analyzer in 48% of the analyses considerably delayed the time to the first diagnostic report and interfered with laboratory routine workflow.ConclusionThe analytical performance of the investigated platforms should be reflected in the context of implementation into the laboratory workflow.

Ultrasound diagnosis of Clostridium difficile-associated diarrhea.

Clostridium difficile colitis is diagnosed using an immunoassay or polymerase chain reaction (PCR) assay for toxins A/B. Since ultrasound is frequently used as a screening test for hospitalized patients suffering from different abdominal morbidities, we searched for sonographic indicators of C. difficile infection (CDI). In a prospective and blinded case-control study, abdominal ultrasound was performed on hospitalized patients for whom stool samples were sent for C. difficile toxin immunoassay. All patients with positive toxin were included as the case group and patients with negative toxin comprised the control group. Sonographic parameters of both groups were compared. Demographic variables of the 67 patients in the toxin-positive group were similar to those of the 71 patients in the toxin-negative group. The sonographic parameters which were found to be associated with CDI included colonic wall thickening, appearing in 61 (91%) patients of the toxin-positive group versus 15 (21%) patients of the toxin-negative group (p < 0.001), and also internal ring (24 versus 0%, p < 0.001), external ring (15 versus 0%, p < 0.001), ascites (24 versus 10%, p < 0.001), and diminution of large bowel content (16 versus 1%, p < 0.001). Bowel wall thickening had high positive and negative predictive values (0.80 and 0.90, respectively), while the other features had only high positive predictive values (0.7-1.0). Abdominal ultrasound may contribute to the diagnosis of C. difficile colitis in patients developing hospital-acquired diarrhea.

Risk factors associated with lower defecation frequency in hospitalized older adults: a case control study.

BackgroundConstipation is highly prevalent in older adults and may be associated with greater frequency of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We investigated the prevalence of lower defecation frequency (DF) and risk factors (including AECOPD) associated with lower DF among hospitalized elderly patients.MethodsWe conducted a retrospective case–control study in a community hospital of Southeast Ohio. Adults aged 65 years or older admitted during 2004 and 2006 were reviewed (N = 1288). Patients were excluded (N = 212) if their length of stay was less than 3 days, discharge diagnosis of Clostridium difficile-associated diarrhea, death or ventilator- dependent respiratory failure during hospitalization. Lower DF was defined as either an average DF of 0.33 or less per day or no defecation in the first three days of hospitalization; cases (N = 406) and controls (N = 670) were included for the final analysis.ResultsApproximately 38% had lower DF in this patient population. Fecal soiling/smearing of at least two episodes was documented in 7% of the patients. With the adjustment of confounders, AECOPD (adjusted odds ratio [AOR] =1.47, 95% confidence interval [CI] =1.01-2.13) and muscle relaxant use (AOR =2.94; 95% CI =1.29-6.69) were significantly associated with lower DF. Supplementation of potassium and antibiotic use prior to hospitalization was associated with lower risk of lower DF.ConclusionsApproximately 38% of hospitalized older adults had lower DF. AECOPD and use of muscle relaxant were significantly associated with lower DF; while supplementation of potassium and antibiotic use were protective for lower DF risk after adjusting for other variables.Electronic supplementary materialThe online version of this article (doi:10.1186/s12877-015-0041-0) contains supplementary material, which is available to authorized users.

Incidence of diarrhea by Clostridium difficile in hematologic patients and hematopoietic stem cell transplantation patients: risk factors for severe forms and death.

We describe the rate of incidence of Clostridium difficile-associated diarrhea (CDAD) in hematologic and patients undergone stem cell transplant (HSCT) at HC-FMUSP, from January 2007 to June 2011, using two denominators 1,000 patient and 1,000 days of neutropenia and the risk factors associated with the severe form of the disease and death. The ELISA method (Ridascreen-Biopharm, Germany) for the detections of toxins A/B was used to identify C. difficile. A multivariate analysis was performed to evaluate potential factors associated with severe CDAD and death within 14 days after the diagnosis of CDAD, using multiple logistic regression. Sixty-six episodes were identified in 64 patients among 439 patients with diarrhea during the study period. CDA rate of incidence varied from 0.78 to 5.45 per 1,000 days of neutropenia and from 0.65 to 5.45 per 1,000 patient-days. The most common underlying disease was acute myeloid leukemia 30/64 (44%), 32/64 (46%) patients were neutropenic, 31/64 (45%) undergone allogeneic HSCT, 61/64 (88%) had previously used antibiotics and 9/64 (13%) have severe CDAD. Most of the patients (89%) received treatment with oral metronidazole and 19/64 (26%) died. The independent risk factors associated with death were the severe form of CDAD, and use of linezolid.

PTH-026 Predictors for all Cause Mortality following Clostridium Difficile Associated Diarrhoea

IntroductionSevere Clostridium difficile associated diarrhoea (CDAD) is an important nosocomial infection, often resulting in severe morbidity or death. The rates of CDAD have increased significantly in the last 2 decades,...

Sa1242 Predictors for All-Cause Mortality Following Clostridium Diffcile Associated Diarrhoea

Introduction Severe Clostridium difficile associated diarrhoea (CDAD) is an important nosocomial infection, often resulting in severe morbidity or death. The rates of CDAD have increased significantly in the last 2 decades, but predictors of outcome are poorly understood. Methods A retrospective cohort study was performed in patients with a diagnosis of CDAD hospitalised at Leeds Teaching Hospitals NHS Trust (LTHT) between January 2011 and December 2011. The data on these cases was collected from electronic patient records and medical notes. Data collected included general demographics, underlying medical conditions, Horn Index, Charlson co-morbidity score, clinical and laboratory data, and the medical treatment given. Death due to any cause either during that hospital stay or within 30 days of discharge from hospital was the primary outcome. Severe CDAD was defined according to the UK Health Protection Agency (HPA) guidelines as WCC > 15 X 109/L, or an acute rising serum creatinine (i.e. > 50% increase above baseline), or a temperature of > 38.5°C, or evidence of severe colitis (abdominal or radiological signs). Logistic Regression analysis was used to identify parameters associated with mortality. SPSS version 17 (IBM Corp, NY) was used to perform the statistical analysis. Results There were 247 patients with a diagnosis of CDAD made in 2011 at LTHT of which 16 were wrongly coded, 5 were treated in the community, 12 had insufficient information in the notes and in 68 patients the medical notes could not be traced. A total of 170 episodes in 146 patients were finally analysed. There were 36 deaths in this group. Patients who were dead were older (mean age 78±12.9 vs 76.6±17.6). Independent predictors of mortality on multivariate analysis included age (OR 1.051, 95% CI 1.009–1.095), Charlson co-morbidity score of ≥3 (OR 3.036, 95% CI 1.209–7.622), Horn Index (Major or Extreme) (OR 4.725, 95% CI 1.818–12.283), Severe CDAD (OR 3.454, 95% CI 1.222–9.760) and in-appropriate treatment of severe CDAD with metronidazole as first line therapy (OR 4.642, 95% CI 1.213–19.193). Factors not found significant included gender, prior use of antibiotics, PPI use, opioid use, prior episodes of CDAD and treatment with vancomycin. Conclusion Predictors of all-cause mortality in patients with CDAD include older age, Charlson score≥3, Horn index ≥3, severe CDAD as defined by the UK HPA and in-appropriate use of metronidazole in severe CDAD. Patients with severe CDAD should not be treated with Metronidazole as first line therapy. Further prospective validation of these results is needed in a multicenter setting. Disclosure of Interest None Declared.

Evaluation of the diagnostic algorithm consisting of enzyme immunoassay for toxins and polymerase chain reaction, for the diagnosis of Clostridium difficile-associated diarrhoea

A total of 1631 stool specimens were tested for Clostridium difficile toxins A and B using an enzyme immunoassay (EIA). C. difficile toxin was detected in 191 (11.7%, 191/1631) cases by EIA. Among the remaining 1440 cases, 102 cases in patients with either antibiotic-associated diarrhoea or hospitalized patients with unexplained leukocytosis (> 15,000/mm³) and fever (≥ 38°C) even though they did not meet the criteria for diarrhoea, were further assessed using a polymerase chain reaction (PCR) for the toxin B gene (tcdB). Thirty-four cases were tcdB-positive (33.3%, 34/102). A total of 225 cases (13.8%, 225/1631) had a stool test result positive for C. difficile toxins. Among these, 145 cases were diagnosed with C. difficile-associated diarrhoea (CDAD): 80.7% (117/145) using the EIA and 19.3% (28/145) using the PCR. In our study, the 2-test algorithm including EIA-toxin assay and PCR test made a more accurate diagnosis of CDAD. Furthermore, the application of clinical situations may be effective in the selection of patients who need confirmatory testing.

The incremental economic burden of clostridium-difficile associated diarrhea among hospitalized immunocompromised patients undergoing chemotherapy.

e16542 Background: Hospital-acquired Clostridium-difficile associated diarrhea (CDAD) results in an estimated $1.3 billion in excess costs in the US. Patients undergoing chemotherapy are at elevated risk of CDAD due to diminished immune response and increased exposure to health care facilities. This study describes the incremental economic burden of CDAD in hospitalized immunocompromised (IC) patients. Methods: IC cases (undergoing chemotherapy or other qualifying conditions) hospitalized with a diagnosis of CDAD having ≥12 months of prior health plan eligibility and age ≥18 years between 1/1/2005 and 10/31/2010 were identified from the HealthCore Integrated Research Database (HIRDSM). Cases were matched to hospitalized IC controls without CDAD diagnosis based on: age±10 years, gender, selected preceding/in-hospital comorbidities and use of antibiotics. Incremental hospital length of stay (LOS) and costs were calculated between matched cases and controls via multivariate methods using a Gamma distribution. Covariates were determined from post-match univariate analysis of baseline characteristics. Results: 3,586 cases were matched to 10,758 controls. Chemotherapy occurred among 91.3% of cases and controls. While age (65±15), gender (53% female), and selected comorbidities were balanced between cases and controls, post-match disparities persisted (p&lt;.001): geographic region (37% vs. 32% Midwest), type of health plan (24 vs. 18% HMO), overall comorbidity burden (6.0±3.6 vs. 6.5±3.7 Deyo-Charlson Comorbidity Index). Cases had a lower incidence of mortality during their index hospitalization (6.7% vs. 7.8%; p&lt;0.0001). Adjusted hospital LOS was significantly greater for cases vs. controls (22.1 days (20.61 to 23.69) vs. 13.67 days (12.74 to 14.67); p&lt;.0001). Incremental hospitalization costs indicated a significantly greater economic burden among cases vs.controls (Δ = $32K ($29K to $35K); p&lt;0.0001). Conclusions: This study indicates that the acquisition of CDAD among immunocompromised patients, of which chemotherapy recipients represented the majority, presents significant incremental economic burden within the hospital setting.

A Superior Test for Diagnosis of Clostridium difficile-Associated Diarrhea in Resource-Limited Settings

In this prospective cohort study, we investigated the prevalence of Clostridium difficile-associated diarrhea (CDAD) in adult patients with nosocomial diarrhea by performing enzyme immunoassay (EIA) for detecting toxins A and B and polymerase chain reaction (PCR) for detecting the presence of the tcdB gene in stool samples. We determined the factors associated with CDAD, and the treatment outcome of CDAD from May 2010 to January 2011. A total of 175 stool samples were tested by EIA and PCR. In total, 26.9% patients tested positive for C. difficile: 12.6% by EIA and 24.0% by PCR. The kappa coefficient and total agreement of both the tests were 0.46 and 83.2%, respectively. Onset of diarrhea after antibiotic administration for 10 days or more (OR, 2.71; 95% CI, 1.14-6.44; P = 0.024) and leukocyte count >15,000 cells/mm(3) (OR, 3.12; 95% CI, 1.24-7.88; P = 0.016) were significantly associated with occurrence of CDAD. The non-response rate to CDAD treatment was 24.1%, and the all-cause mortality rate was 31.9% in the CDAD group as against 35.9% in the non-CDAD group (P = 0.721). In our study, the performance of direct PCR of stool samples for detecting tcdB was better, with the number of positive results for stool toxins A and B being twofold higher than that in the case of EIA. Patients who have diarrhea after receiving antibiotics for 10 days or more or those who have a leukocyte count of >15,000 cells/mm(3) should be investigated for CDAD.

Diabetes mellitus as a risk factor for recurrence of Clostridium difficile infection in the acute care hospital setting

Clostridium difficile-associated diarrhea (CDAD) is increasingly encountered in the acute care setting with rates of infection increasing dramatically since 2001. Reoccurring episodes are being seen with increasing frequency. The purpose of this study was to examine risk factors specifically associated with CDAD recurrence in an urban medical center. This study was conducted in a 651-bed, acute care teaching hospital in an urban community in northeastern New Jersey. We examined the medical records of subjects discharged from the institution with a diagnosis of CDAD over the 6-year period January 1, 2003, to December 31, 2008. Inclusion in the study required clinical signs and symptoms of CDAD and the presence of C difficile toxins A/B. This cohort of 247 subjects was divided into 2 groups: those who were not readmitted with CDAD within 6 months (n = 171) and those who required readmission for CDAD within 6 months of discharge from their last admission (n = 76). Both hypoalbuminemia (odds ration [OR], 1.74, 95% confidence interval [CI]: 1.10-2.77; P = .02) and diabetes (P < .0001; OR, 3.04; 95% CI: 1.84-5.03; P < .0001) were considered as independent risk factors. After adjustment for potential confounders, hypoalbuminemia was found to be race dependent (OR, adjusted for black race: 1.62; 95% CI: 0.93-2.82; P = .09); however, diabetes was found to be a significant independent risk factor for CDAD recurrence (adjusted OR ranged from 3.79 to 5.46, minimum lower 95% confidence level: 2.01, all P values <.0001). We have demonstrated that diabetes is an important risk factor for recurrence of CDAD. Although previous have concluded that hypoalbuminemia is associated with CDAD recurrence, our data suggest that this association may have some dependence on race or ethnicity.

Proton pump inhibitors as a risk factor for recurrence ofClostridium-difficile-associated diarrhea

To investigate the risk factors for Clostridium-difficile-associated diarrhea (CDAD) recurrence, and its relationship with proton pump inhibitors (PPIs). Retrospective data of 125 consecutive hospitalized patients diagnosed with CDAD between January 2006 and December 2007 were collected by medical chart review. Collected data included patient characteristics at baseline, underlying medical disease, antibiotic history before receiving a diagnosis of CDAD, duration of hospital stay, severity of CDAD, concurrent treatment with PPIs, laboratory parameters, response to CDAD therapy, and recurrence of disease within 90 d of successful treatment. Various clinical and laboratory parameters were compared in patients in whom CDAD did or did not recur. Of the 125 patients (mean age, 67.6 +/- 13.9 years) that developed CDAD, 98 (78.4%) did not experience recurrence (non-recurrent group) and 27 (21.6%) experienced one or more recurrences (recurrent group). Prior to the development of CDAD, 96% of the 125 patients were prescribed antibiotics, and 56 (44.8%) of the patients received PPIs. Age older than 65 years (P = 0.021), feeding via nasogastric tube (NGT) (P = 0.045), low serum albumin level (P = 0.025), and concurrent use of PPIs (P = 0.014) were found to be risk factors for CDAD recurrence by univariate analysis. However, sex, length of hospital stay, duration and type of antibiotics used, severity of disease, leukocyte count and C-reactive protein (CRP) were not associated with risk of CDAD recurrence. On multivariate analysis, the important risk factors were advanced age (> 65 years, adjusted OR: 1.32, 95% CI: 1.12-3.87, P = 0.031), low serum albumin level (< 2.5 g/dL, adjusted OR: 1.85, 95% CI: 1.35-4.91, P = 0.028), and concurrent use of PPIs (adjusted OR: 3.48, 95% CI: 1.64-7.69, P = 0.016). Advanced age, serum albumin level < 2.5 g/dL, and concomitant use of PPIs were found to be significant risk factors for CDAD recurrence.

Proton Pump Inhibitor Therapy Alleged Accomplice or Innocent Bystander in the Changing Epidemiology of Clostridium Difficile Associated Diarrhea?

Purpose: Over the past decade there has been an increase in the number of hospital patients with Clostridium difficile-associated diarrhea (CDAD). It has become a major hospital acquired pathogen and understanding the potential risk factors for CDAD has become an important focus of research. One of the controversial associations commonly stated of increasing ones risk of acquiring CDAD is proton pump inhibitor (PPI) therapy (Am J Gastroenterol 2008; 103:2308-2313). This retrospective chart review study was done to evaluate the incidence of CDAD in hospitalized patients who were taking PPI therapy. Methods: An IRB approved retrospective case-control chart review study was conducted consisting of 209 randomly chosen hospitalized patients charts admitted between 1/01/05 to 7/01/08 that were found to have a discharge diagnosis of CDAD by ICD9 coding (008.45). Charts were then analyzed for inclusion criteria to determine if patients had a positive C.difficile cytotoxin assay performed during that admission, if PPI therapy was used continuously for at least three days prior to that positive cytotoxin stool assay, and whether the patients were over the age of eighteen. Exclusion criteria for the study consisted of having no prior history of CDAD within the past 6 months. In addition, a randomly chosen age and gender matched control group of 168 charts was obtained during the same time frame, with the only inclusion/exclusion criteria required be that the patient be above the age of eighteen, with no diarrhea symptoms while in the hospital and no positive C. difficle cytotoxin assays during admission. Results: Of the 209 hospitalized patient charts reviewed, 149 met the inclusion criteria for the study while 60 were excluded. Cases were not found to be more likely than controls to have acid suppressive therapy with PPI onboard while admitted to the hospital, 80 (53.7%) vs. 99 (58.9%) with a P=0.8081 by Cochran-Mantel-Haenszel analysis. Conclusion: This retrospective study further argues against the alleged risk factor association that PPI therapy will increase a hospitalized patient's chance for developing CDAD due to gastric acid suppression. Further randomized prospective studies should be sought to further clarify this discrepancy in correlation.

Laboratory diagnosis of Clostridium difficile-associated diarrhoea: microbiologists (should) do it with culture

Sir,Some infectious agents are like battle-hardened guerrilla soldiers-they do not surrender, just retreat and bide their time until they can return with a vengeance. A striking example: Clostridiu...

Increasing incidence of Clostridium difficile-associated diarrhea in inflammatory bowel disease

Introduction and aimOver the last decade a rise in Clostridium difficile-associated diarrhea (CDAD) has been observed. A higher incidence of CDAD has also been suggested in patients with inflammatory bowel disease (IBD), and may be a challenging factor in the differential diagnosis of flares. It is unclear if the increase is caused by the enhanced use of immunosuppressive therapy in IBD. We investigated if CDAD infection is increasing in IBD patients and evaluated outcome and possible predisposing factors. MethodsThrough an electronic database of the Laboratory of Microbiology of our hospital (tertiary referral center), all stool samples from patients admitted for diarrhea and hospitalized on gastroenterology wards between January 2000 and January 2008 were reviewed for diagnosis of CDAD. For analysis, we compared two periods of equal duration. ResultsA total of 57 patients were diagnosed with CDAD, of whom 26.3% had concomitant IBD. A 3.75-fold increase in CDAD was observed between period 1 and period 2, irrespective of underlying IBD and with a comparable total number of analyzed stool samples between both periods. Non-IBD patients were significantly older. Antibiotic use three months prior to the infection was higher in non-IBD (29/42 or 69%) than in IBD patients (6/15 or 42%) (p = 0.047). Nine IBD patients were on concomitant immunomodulators, and this was not different between period 1 and period 2. Most patients had a successful outcome and only one patient with ulcerative colitis needed semi-urgent colectomy. Two patients died in the non-IBD group. The duration of hospital stay was significantly lower in IBD patients. ConclusionWe observed a significant rise in CDAD in both IBD and non-IBD. The clinical outcome was favorable with only one IBD patient needing semi-urgent colectomy. Because C. difficile can mimic an IBD flare, it is essential that clinicians are vigilant to this complication. The use of immunosuppressive drugs in IBD does not influence the risk.

Comparaison de trois tests immunoenzymatiques pour la détection des toxines A et B de Clostridium difficile

Diagnosis of Clostridium difficile-associated diarrhea is classically based on detection of toxin A and/or toxins A+B by using several techniques. However, these techniques show important differences in terms of sensitivity and specificity. In this work, we compared three commercial immunoenzymatic tests for detecting C. difficile toxins. We used three immunoenzymatic techniques: ELISA Premiertrade mark Toxins A and B (Meridian), ImmunoCard (IC) Toxins A and B (Meridian), and Triage (TRI) Antigen GDH and Toxin A (Biosite). Culture on the specific media C. difficile (bioMérieux) was performed in parallel. During two years, 898 stool specimens have been tested by using the three different techniques. According to the manufacturer's recommendations (sample positive if optical density [OD] value greater or equal to 0.15), 205 (22.8%) were positive for ELISA. Among them, 65 (31.7%) were negative for all other tests, and they have been considered as false-positive results. This discrepancy led us to choose other OD values (greater than 0.75: positive result; 0.15-0.75: limit result). For limit results, IC, TRI, antigen GDH, and culture methods were positive in 30, 2, 41, and 29% of cases, respectively, whereas for positive results (>0.75), they were positive in 82, 54, 84, and 76% of cases, respectively. ELISA and IC tests are the most powerful and are concordant together if interpretation is performed with OD values redefined by the microbiology laboratory. The choice of the technique to use depends on the number of samples to analyze, the rapidity of the result, and the cost.

Application of Isothermal Helicase-Dependent Amplification with a Disposable Detection Device in a Simple Sensitive Stool Test for Toxigenic Clostridium difficile

Enzyme immunoassays (EIAs) are commonly used for the diagnosis of cases of Clostridium difficile-associated diarrhea (CDAD). However, these EIAs have high false-negative rates, even in patients with severe clinical disease. We have developed an IsoAmp CDAD test using a simple and user-friendly procedure to identify toxigenic C. difficile in feces. After DNA extraction from fecal samples, both the conserved sequence of the 5'-end fragment of the C. difficile tcdA toxin gene and competitive amplification internal control sequence were amplified using helicase-dependent amplification. Amplification products were detected using a novel amplicon-containment detection device. The analytical sensitivity of the assay was 20 copies of C. difficile genomic DNA per reaction. Evaluation of the clinical sensitivity and specificity of the IsoAmp CDAD test versus an EIA method using a PCR method as the reference standard revealed 100% sensitivity and 100% specificity for the IsoAmp CDAD test compared with 90.9% sensitivity and 100% specificity for the EIA method. Because the IsoAmp CDAD test requires no expensive equipments for nucleic acid amplification or detection and can be performed on a random access basis, the test provides a practical alternative to immunoassays for the diagnosis of CDAD with improved sensitivity.

Infection control measures to limit the spread of Clostridium difficile

Clostridium difficile-associated diarrhoea (CDAD) presents mainly as a nosocomial infection, usually after antimicrobial therapy. Many outbreaks have been attributed to C. difficile, some due to a new hyper-virulent strain that may cause more severe disease and a worse patient outcome. As a result of CDAD, large numbers of C. difficile spores may be excreted by affected patients. Spores then survive for months in the environment; they cannot be destroyed by standard alcohol-based hand disinfection, and persist despite usual environmental cleaning agents. All these factors increase the risk of C. difficile transmission. Once CDAD is diagnosed in a patient, immediate implementation of appropriate infection control measures is mandatory in order to prevent further spread within the hospital. The quality and quantity of antibiotic prescribing should be reviewed to minimise the selective pressure for CDAD. This article provides a review of the literature that can be used for evidence-based guidelines to limit the spread of C. difficile. These include early diagnosis of CDAD, surveillance of CDAD cases, education of staff, appropriate use of isolation precautions, hand hygiene, protective clothing, environmental cleaning and cleaning of medical equipment, good antibiotic stewardship, and specific measures during outbreaks. Existing local protocols and practices for the control of C. difficile should be carefully reviewed and modified if necessary.

Evaluation of Rapid Assay (Tox A/B Quik Chek) for the Detection ofClostridium difficileToxins A and B

Background: Toxin immunoassay is widely used for rapid diagnosis of Clostridium difficile-associated diarrhea. The aim of this study was to evaluate the performance of Tox A/B Quik Chek test (TECHLAB, Blacksburg, VA, USA) compared to toxigenic culture. Methods: From September 2006 to August 2007, 959 stools were examined by Tox A/B Quik Chek test and toxigenic culture (C. difficile culture plus tcdB PCR using colonies obtained from culture). Results: Compared to the results of toxigenic culture, the sensitivity and specificity of Tox A/B Quik Chek test were 47.5% and 97.5%, respectively. Conclusion: The sensitivity of Tox A/B Quik Chek test was not high, but the specificity was high. Although Tox A/B Quik Chek test alone is not sufficient to diagnose Clostridium difficile-associated diarrhea, it may aid rapid diagnosis, early treatment and prevention of nosocomial spread of the infection, if supplemented by C. difficile culture or tissue culture cytotoxin assay. (Korean J Clin Microbiol 2008;11: 112-116)

Evaluation of Two Rapid Immunochromatography Tests for the Detection of Clostridium difficile Toxins

The aim of the study was to evaluate the performance of two rapid immunochromatography tests, the Tox A/B Quick Chek (TechLab) and the ImmunoCard Toxins A&B test (Meridian), in addition to the older Tox A/B ELISA, against PCR detection of the tcdB gene. Two hundred patient-unique stool specimens were tested. In comparison to the polymerase chain reaction results, the sensitivity and specificity of the two rapid tests were 94.7% and 97.2%, respectively; corresponding values for the ELISA were 93.6% and 94.3%. Findings on the rapid tests showed a 96% correlation with polymerase chain reaction assay and a 94% correlation with ELISA. Considering the importance of early and appropriate diagnosis of Clostridium difficile-associated diarrhea, rapid immunochromatography tests may be of great benefit to practitioners.