The role of flexible sigmoidoscopy in the diagnosis of Clostridium difficile-associated diarrhea / 대한내과학회지

BACKGROUND/AIMS: Clostridium difficile is an important cause of diarrhea in hospitalized patients. C. difficile-associated diarrhea (CDAD) is usually diagnosed following a stool test for C. difficile cytotoxin or stool culture for the presence of toxigenic C. difficile. However, the reported sensitivities of these tests are variable. Sigmoidoscopy may be an effective diagnostic method in patients with a false-negative stool test for cytotoxin. This study examined the role of flexible sigmoidoscopy in the diagnosis of CDAD. METHODS: Among the patients who had diarrhea and were examined with sigmoidoscopy in Eulji University Hospital between January 2005 and July 2008, 102 patients suspected of having antibiotic-associated diarrhea (AAD) based on their clinical symptoms were enrolled. Of the 102 patients, 74 were diagnosed with CDAD based on C. difficile cytotoxin or sigmoidoscopic findings of pseudomembranous colitis. The medical records of these 74 patients were reviewed retrospectively. RESULTS: Of the 74 patients, sigmoidoscopic findings revealed a pseudomembrane in 63 patients (85.1%) and colitis in nine (12.2%), while two patients (2.7%) appeared normal. Of the 63 patients with pseudomembranous colitis at sigmoidoscopy, the stool C. difficile cytotoxin assay was negative in 27 (42.9%). CONCLUSIONS: Flexible sigmoidoscopy was highly sensitive in pseudomembranous colitis and is useful in diagnosing patients with a delayed or negative stool test for C. difficile cytotoxin. Therefore, we recommend flexible sigmoidoscopy in patients suspected of having C. difficile-associated diarrhea for the diagnosis of CDAD.

Antibiotic associated diarrhea in children.

Context: Keeping in view the recent flooding of the Indian market with antibiotic and probiotic combinations, we decided to look at the prevalence of antibiotic associated diarrhea (AAD) and Clostridium difficile infection (CDI) in children and reviewed evidence available for use of probiotics in the prevention of AAD. Evidence acquisition: We did a PubMed, Medline and Cochrane libary search for literature available in last 25 years. Results: Prevalence of antibiotic associated diarrhea (AAD) is around 11%. Children younger than 2 years and type of antibiotics are the two risk factors identified for AAD. For the pediatric population, CDI reportedly decreased in a tertiary care hospital in India, though number of suspected samples tested increased. The incidence of community acquired CDI is increasing in the pediatric population also. Detection of toxin A and B by enzyme linked immunosorbent assay (ELISA) and detection of toxin B by tissue culture form the mainstay in the diagnosis of C. difficile. Most of the AAD would respond to only discontinuation or change of the antibiotic. Oral metronidazole or oral vancomycin are drugs of choice for CDI. Probiotics reduce the risk of AAD in children and for every 7-10 patients one less would develop AAD. Conclusion: Prevalence of AAD is low and majority will respond to discontinuation of antibiotic. CDI is uncommon in children. Probiotics will prevent AAD in only 1 in 7 children on antibiotics. We need cost effectiveness studies to decide the issue of needing a probiotic antibiotic combination to prevent AAD.

Evaluation of Quantitative culture of Clostridium difficile From Fecal Specimens for the Diagnosis of C. difficile-associated Disease / 대한임상미생물학회지

BACKGROUND: C. difficile-associated diarrhea (CDAD), the most frequently identified cause of nosocomial diarrhea, results from the overgrowth of cytotoxin (toxin B)-producing strains. The aim of this study was to evaluate the quantitative culture of Clostridium difficile to improve the laboratory diagnosis of CDAD. METHODS: The quantitative culture and cytotoxin gene results were evaluated based on the findings of colonoscopy and/or histology of the biopsy specimens. RESULTS: Among the 402 specimens with cytotoxin-positive isolates, 301 (74.9%) contained > or =106 CFU/mL of C. difficile. Nine (60%) of the 15 pseudomembranous colitis patients yielded > or =106 CFU/mL of toxigenic isolate. The proportion of cytotoxin gene-positive isolates was higher in the specimens with > or =106 CFU/mL of C. difficile than in those with 102-<103 CFU/mL (86.5% vs. 66.7%). CONCLUSIONS: Quantitative culture may aid in the interpretation of toxigenic C. difficile culture results, and reduce false positivity, thus avoiding unnecessary treatment.