Idiopathic Myointimal Hyperplasia of Mesenteric Veins (IMHMV) with two spontaneous bowel perforations: A case report and literature review.

Introduction And Importance: Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is a poorly understood disorder which poses a diagnostic challenge to clinicians and pathologists. Here we have described the case of a male patient with IMHMV along with a presumed history of ulcerative colitis for 1 year.

Case Presentation: A 55-year-old male presented to the OPD with history of chronic abdominal pain. Clinical and radiological examination coupled with endoscopic findings resulted in the patient being wrongly diagnosed to be a case of ulcerative colitis and was managed accordingly. Throughout his multiple hospital visits following treatment for ulcerative colitis, the patient was persistently symptomatic. He presented with 10 days history of increasing abdominal pain and constipation following which he developed spontaneous colonic perforation for which he underwent exploratory laparotomy left colectomy and Hartman's procedure. The final pathology of the resected colon found to be consistent of Idiopathic myointimal hyperplasia of the mesenteric veins and ischemic bowel changes.

Clinical Discussion: The absence of clear-cut endoscopic biopsy findings of ulcerative colitis made radiological picture to be the mainstay for diagnosis, which was inaccurate and exposed the patient to unnecessary treatment with immuno-modulators thus resulting in poor response to treatment. As the disease progressed, further narrowing of the vessels made the clinical picture to look closer to ischemic bowel pathology as the patient developed a top surgical emergency (i.e. bowel perforation). Such pathological finding (IMHMV) can only be diagnosed in a fully prepared tissue histology, but rather be considered when no other consistent alternative diagnosis was found.

Conclusion: The treating physicians must definitely consider the possibility of idiopathic myointimal hyperplasia of mesenteric veins when similar manifestations are encountered in biopsy specimens of old cases with suspected inflammatory bowel disease or non-occlusive ischemia of the distal colorectum.