Pseudomembranous colitis

Abstract

Three basic histopathologic patterns which may be seen in rectal biopsies from patients with pseudomembranous colitis are described, based on a study of 29 cases. The spectrum of change is illustrated and the problems of differential diagnosis are discussed, from a non diagnostic proctitis at one extreme to acute ischemia at the other. In the differential diagnosis of the acute colitic, the importance of urgent rectal biopsy and a carefully taken drug history is stressed. The association of pseudomembranous colitis with pre existing disease and antibiotic therapy is confirmed. It is suggested that these cause local mucosal damage and may trigger the first part of a local Shwartzman reaction. Capillary microthrombosis may then play a part in producing the mucosal necrosis seen later in the disease.