Idiopathic myointimal hyperplasia of mesenteric veins: a rare mimic of idiopathic inflammatory bowel disease.

Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood disease that occurs in the rectosigmoid colon of predominantly young, previously healthy male patients. IMHMV typically requires segmental resection due to complications after a relatively protracted clinical course. This disease presents a challenging diagnostic dilemma for the clinician because it is initially often confused with chronic idiopathic inflammatory bowel disease. We report a case of IMHMV, illustrate endoscopic and histopathologic features, and review key characteristics of this rare entity.