Antibiotic-associated colitis: a retrospective study of fifteen cases.

Fifteen cases of antibiotic-associated colitis were reviewed in a retrospective study of all the cases seen in a general hospital in the period 1970--7. Nine of these cases were diagnosed as pseudomembranous colitis. This was found mostly in patients over 65 years of age, where it resulted in severe illness with 70% mortality. The antibiotics involved included ampicillin, penicillin, clindamycin, erythromycin and co-trimoxazole (Septrin). Pseudomembranous colitis is a serious hazard in the elderly and may be caused by a wide range of antibiotics in common use.