Abstract

Four patients are described who developed pseudomembranous colitis in association with clindamycin therapy. Rectal biopsies from two patients were studied with the electron microscope and compared with the ultrastructural appearance of the rectal mucosa from seven normal people. Ultrastructural evidence for a viral colitis was obtained. The significance of the clindamycin therapy to the viral colitis and the contribution of the viral colitis to the clinical state are discussed.