ABSTRACT
Clostridium difficile is a frequently identified cause of nosocomial gastrointestinal disease. It has been proved to be a causative agent in antibiotic-associated diarrhea, antibiotic-associated colitis, and pseudomembraneous colitis. This study was aimed to determine the prevalence of C.difficile- associated diarrhea in hospitalized patients with nosocomial diarrhea. The 942 hospitalized patients stool samples with nosocomial diarrhea were collected at three hospitals in Tehran from Dec 2002 to Feb 2004.All the stool samples were cultured and in 97 [prevalence: 10.9%] samples grew C.difficile that 57 [prevalence: 6.1%] isolates were toxigenic by cytotoxicity assay and so 57 patients had C.difficile- associated diarrhea. Results of statistical analysis showed significant difference between the rate of C.difficile associated diarrhea and the patients ages [P<0.05]