Differentiating small bowel Crohn's disease from lymphoma. Role of rectal biopsy.

Crohn's disease and lymphoma limited to the small bowel may have similar clinical and radiologic features. This diagnostic dilemma was encountered in 5 adolescent patients with an eventual diagnosis of Crohn's disease, all of whom had normal sigmoidoscopic and radiographic evaluations of the colon. Rectal and colonic biopsies in 3 revealed granulomas and focal colitis supportive of the diagnosis of Crohn's disease and prevented laparotomy. A careful search for occult colonic involvement in similar patients with Crohn's disease may obviate the need for diagnostic surgery.