Clostridium difficile colitis associated with the use of antineoplastic agents.

Eight patients are presented in whom treatment with antineoplastic agents, in particular the folic acid antagonist methotrexate, precipitated Clostridium difficile-related diarrhoea and pseudomembranous colitis. The clinical presentation of these patients was identical to that encountered in patients developing antibiotic associated diarrhoea and colitis. Clostridium difficile-related diarrhoea and colitis should be suspected in any patient developing diarrhoea during the course of anti-neoplastic chemotherapy or within three weeks of its cessation. This complication is effectively treated with oral vancomycin.