Idiopathic Myointimal Hyperplasia of the Mesenteric Veins: A Case Report and Scoping Review of Previously Reported Cases From Clinical Features to Treatment

Endovascular Stenting for Idiopathic Stenosis of the Superior Mesenteric Vein: A Case Report

Idiopathic superior mesenteric vein (SMV) stenosis, where no clear causative factor is identifiable, remains a clinical rarity. We present a detailed case report of a patient with idiopathic stenosis of the SMV who underwent successful endovascular stenting. This report outlines the patient's clinical presentation, diagnostic imaging findings, procedural approach by the interventional radiology team, and subsequent management. Endovascular stenting is a viable therapeutic option for patients with idiopathic SMV stenosis. This case demonstrates that with appropriate interventional and post-procedural management, long-term stent patency and thrombosis prevention can be achieved. The success of this case encourages further investigation into endovascular treatments for venous stenoses.

Mesenteric Arteriovenous Dysplasia/Vasculopathy: Deciphering a Rare, Deceptive, Diagnostic Dilemma

Mesenteric arteriovenous dysplasia/vasculopathy (MAVD/V) is an exceedingly rare noninflammatory vascular disorder affecting small-calibre mesenteric arteries and veins. This report details a case of a 51-year-old male diagnosed with MAVD/V following abdominal pain and vomiting. Surgical exploration revealed distinctive smooth muscle collarette around subserosal arteries and veins. The rarity of this condition, with only 13 cases reported globally, underscores the importance of recognizing this rare entity to prevent misdiagnosis. Surgical resection remains the curative approach, ensuring a disease-free state after surgery. Awareness of MAVD/V is crucial for accurate diagnosis and avoiding unnecessary prolonged management.

Atypical presentation of a rare disorder; idiopathic myointimal hyperplasia of mesenteric veins (IMHMV): Report of two cases

INTRODUCTION

Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare type of chronic colonic ischemia. Patients commonly present with progressive abdominal pain, bloody diarrhea, and weight loss. IMHMV is a common mimicker of inflammatory bowel disease. However, medical management does not have a primary role and curative treatment is surgical resection.

PRESENTATION OF CASE

We report two cases of IMHMV with atypical presentation. The first is an 82-year-old male who had refractory, painless, explosive, and non-bloody diarrhea initially treated with antidiarrheal medications and dietary changes to no effect. Colonoscopy was not clarifying. However, CT scan had characteristic findings of IMHMV. He underwent partial colectomy and recovered well. The second case is a 59-year-old male who had recurrent episodes of sudden, massive diarrhea. He was initially treated for diverticulitis based on colonoscopy findings but did not experience relief. Eventually, MRI of the abdomen was suggestive of IMHMV. He underwent surgical resection, which confirmed the diagnosis of IMHMV. He was treated for Clostridioides difficile diarrhea five months after surgery and pulmonary embolism seven months after surgery. With over a year of follow up, neither has had disease recurrence.

DISCUSSION

Diagnosis and treatment of rare disorders like IMHMV is challenging, especially when they mimic common entities or present in atypical ways.

CONCLUSION

We present two cases to highlight IMHMV as part of the differential for colitis-like symptoms. These cases demonstrate the importance of diagnostic imaging in diagnosis. Diagnostic uncertainty can lead to exposure to ineffective medical treatments and delay in curative surgery.

Idiopathic myointimal hyperplasia of the mesenteric veins: A systematic review of surgical management

BACKGROUND

Idiopathic myointimal hyperplasia of the mesenteric veins is an extremely rare non-thrombotic mesenteric veno-occlusive disease. The management of idiopathic myointimal hyperplasia of the mesenteric veins is not well-established, and although surgery is the mainstay of treatment, the optimal operation remains unclear. Therefore, we aimed to perform a systematic review to assess the various surgical procedures and associated outcomes for patients with idiopathic myointimal hyperplasia of the mesenteric veins.

METHODS

A systematic search for articles published from 1946 to April 2022 in MEDLINE, EMBASE, Cinahl, Scopus, Web of Science, and Cochrane Library databases is reported. In addition, we report 4 cases of idiopathic myointimal hyperplasia of the mesenteric veins managed at our institution until March 2023.

RESULTS

A total of 53 studies and 88 patients with idiopathic myointimal hyperplasia of the mesenteric veins were included. Most (82%) were male patients, with a mean age of 56.6 years old. The majority (99%) of patients required surgery. Most reports described the involvement of the rectum and sigmoid colon (81%). The most common surgical procedures were Hartmann's procedure (24%) and segmental colectomy (19%); completion proctectomy with ileal pouch-anal anastomosis was performed in 3 (3.4%) cases. In 6 (6.8%) cases, idiopathic myointimal hyperplasia of the mesenteric veins was suspected preoperatively and managed with elective surgery. Four (4.5%) complications were reported. Nearly all (99%) patients achieved remission with surgical intervention.

CONCLUSION

Idiopathic myointimal hyperplasia of the mesenteric veins is a rare pathologic entity infrequently suspected preoperatively and typically diagnosed after surgical resection. Surgical resection with Hartmann's procedure or segmental colectomy was most commonly performed, with completion proctectomy and ileal pouch-anal anastomosis reserved for cases of extensive rectal involvement. Surgical resection was safe and effective, with a low risk of complications and recurrence. Surgical decision-making should be based on the extent of the disease at the time of presentation.