Noninfectious colitides: collagenous colitis, lymphocytic colitis, diversion colitis, and chemically induced colitis.

Approximately 10% of patients with chronic diarrhea carry a diagnosis of microscopic colitis. The endoscopic appearance of both collagenous colitis and lymphocytic colitis may be normal; however, biopsies confirm the diagnosis. Available treatments include antidiarrheals, bismuth salicylate, and budesonide. Although most patients with fecal diversion may have endoscopic evidence of colitis, a much smaller percentage of patients are symptomatic. Some cases of diversion colitis respond to treatment with short-chain fatty acid enemas; however, return of the fecal stream is the most successful therapy. A variety of oral, intravenous, and per rectum chemicals may cause colitis; symptoms usually abate when chemical exposure is discontinued.