Pseudomembranous colitis associated with antibiotics.

Colitis associated with antibiotics, particularly with lincomycin and clindamycin, is a well established entity. The colitis may be clinically and radiologically very difficult to distinguish from inflammatory bowel disease, including Crohn's disease and ulcerative colitis. A wide spectrum of pathological features is described with various antibiotics. However, the pathological picture in the pseudomembranous form is quite distinctive. The most important histological findings include a "mushroom-like" or "explosive" appearance of the pseudomembrane with a sudden transition to normal mucosa adjacent to the lesion. Rectal biopsy is both an accurate and a rapid method of establishing the diagnosis.