Overestimation of ulcerative colitis due to melanosis coli.

Melanosis coli is a benign pigment deposition in the colonic mucosa that can be seen at the time of colonoscopy especially in patients with history of laxative use. In conditions in which the endoscopic findings influence therapeutic decisions, melanosis coli can lead to overestimation of disease aggressiveness and unnecessary therapy. We describe a case in which the finding of melanosis coli affected the treatment of a patient with mild ulcerative colitis exacerbation.