Comparison of five regimens for treatment of experimental clindamycin-associated colitis.

The hamster model of clindamycin-induced enterocolitis was studied to determine the natural course of the disease and the response to five therapeutic regimens. Tissue culture assays of stools from untreated animals showed that colitis toxin is present at low titers within 24--36 hr after challenge with clindamycin; titers of toxin in subsequent specimens of stool increased progressively until the animals died on days 2--4 after challenge. Therapeutic regimens tested in this model were initiated 24 hr after clindamycin challenge when the majority of the animals had evidence of colitis toxin. Methylprednisilone, an anion exchange resin, and gas gangrene polyvalent antitoxin had a minimal effect on toxin titers in stool and failed to delay substantially death due to enterocolitis. Vancomycin and tetracycline eliminated toxin in stools and delayed death. However, the salutary effects of these antibiotics were noted only during the course of their administration since all animals died of enterocolitis and had high titers of toxin when treatment was discontinued.