Antibiotic-associated diarrhoea and pseudomembranous colitis caused by Clostridium difficile. A review of 40 cases.

We found antibiotic-associated diarrhoea (AAD) and pseudomembranous colitis caused by Clostridium difficile in 19% of patients with diarrhoea related to antibiotic therapy or with diarrhoea for which no other cause could be found. Ampicillin, cephalosporins and co-trimoxazole appear to be the agents most commonly associated with this complication. The clinical presentation of AAD falls into two categories: (i) an early-onset type characterized by severe diarrhoea with watery stools which may contain mucus; and (ii) a late-onset variety characterized by chronic, persistent diarrhoea with bulky stools. A definitive diagnosis was made in all cases by the detection of the cytotoxin of Cl. difficile in patients' stools using tissue culture assay. Discontinuation of the implicated agent when possible together with a 14-day course of oral vancomycin effected a cure in 90% of patients. The remaining 10% were successfully treated with a similar course of oral bacitracin.