Colonic hemorrhage from a solitary minute ulcer. Report of three cases.

Three patients with massive lower gastrointestinal bleeding are reported. In all cases, the bleeding source was localized by emergency selective mesenteric angiography. The histologic lesion found in the resected specimen consisted of a minute mucosal ulcer with an abnormally large eroded submucosal artery without evidence of true angiodysplastic changes. The clinicopathological picture is similar to the rare solitary stomach ulceration, described as "Exulceratio simplex Dieulafoy."