Idiopathic myointimal hyperplasia of the mesenteric veins: Case report and review of the literature.

In 1991, Genta and Haggitt described four patients with segmental ischemic colitis caused by idiopathic myointimal hyperplasia in the small mesenteric veins (IMHMV). There are now 33 published cases of IMHMV in the literature; however, this condition is still sufficiently rare that it poses a diagnostic challenge to pathologists and clinicians and is often clinically or histologically confused with inflammatory bowel disease (IBD) or ischemic colitis. IMHMV is characterized by intimal smooth muscle hyperplasia resulting in thickened small and medium-sized mesenteric veins (with arterial sparing). Clinically, it presents with symptoms that mimic IBD, such as bloody diarrhea, abdominal pain, and weight loss. Surgical resection appears to be curative. The present case describes a 63-year-old Vietnamese man with cardiovascular risk factors who was diagnosed with IMHMV after many months of severe symptoms. A review of the current literature follows the case report.