Antibiotic-Associated Pseudomembranous Colitis Due to Toxin-Producing Clostridia

A substance producing cytotoxicity in tissue culture was detected in stool specimens from all of four patients with pseudomembranous colitis due to antibiotics and in one of 54 with antibiotic-associated diarrhea. These stools also caused enterocolitis when injected intracecally into hamsters. On each occasion, cytotoxicity in tissue culture and enterocolitis in hamsters were neutralized by pretreatment with gas-gangrene antitoxin. The toxicity in both tissue cultures and hamsters could be reproduced with broth cultures of clostridia strains isolated from four of the five stools. These results suggest that toxin-producing clostridia are responsible for antibiotic-associated pseudomembranous colitis. (N Engl J Med 298:531–534, 1978) PSEUDOMEMBRANOUS colitis has been recognized since the 1880's as a severe gastrointestinal lesion associated with a variety of conditions.¹ In recent years, the majority of cases have been ascribed to antimicrobial treatment. Clindamycin and lincomycin have been incriminated most often, but cases have been associated with a number of other antimicrobial agents. Despite extensive research, no clearly defined etiologic mechanism has been described. Two recent lines of investigation have suggested that a toxin produced by a bacterial component in the intestinal flora may be responsible. In the first place, Larson et al. recently reported that stools from patients with antibiotic-associated.