Idiopathic myointimal hyperplasia of the mesenteric veins.

Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is caused by proliferation of smooth muscle cells in the wall of small mesenteric veins and venules with accumulation of a proteoglycan matrix leading to a non-thrombotic, non-inflammatory venous occlusion resulting in venous ischemia. IMHMV is a rare and poorly understood disease, with <20 case reports in the literature. The purpose of this report is to describe the case of a 63-year-old man who presented with this condition that resulted in colonic ischemia necessitating surgical resection. The cause of IMHMV in this patient was attributed to a Chinese herbal supplement used for degenerative osteoarthritis of the knees. A brief review of the literature is provided along with the case report.