Clostridium difficile colitis.

We reviewed all rectal biopsies performed on patients with proven C. difficile infection between 1977 and 1982 (36 patients). All patients were symptomatic and all had received antibiotic treatment recently, the commonest antibiotic treatment being ampicillin or amoxycillin. There was poor correlation between the histological appearances and the severity of symptoms. A range of histological appearances was observed: normal (8%), congestion and edema (8%), nonspecific colitis (3%), infective colitis (28%) and pseudomembranous colitis (53%) (PMC). Most cases of PMC showed 'early' features, involving predominantly the surface epithelium, where attenuation and inflammation, intraepithelial microabscesses, and small eruptive lesions were seen. Recognition of these features, in the context of an acute infective-type colitis, may lead to early diagnosis of C. difficile colitis.