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

Kim, Sae Hee; Jung, Sung Hee; Lee, Yun Jung; Hyeon, Woo Jin; Yoo, Young Wook; Lee, Hyang Ie; Yang, Hyeon Woong; Kim, Anna; Cha, Sang Woo

Abstract

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.