Sclerosing Mesenteritis: A Concise Clinical Review for Clinicians

Sclerosing mesenteritis (SM), an idiopathic nonneoplastic condition affecting 0.18% to 3.14% of the population, is characterized by chronic fat necrosis, inflammation, and fibrosis most commonly of the mesentery of the small intestine. Sclerosing mesenteritis typically presents in the fifth or sixth decade of life, where patients with a history of abdominal surgery and/or autoimmune disease may be at higher risk. While many patients are asymptomatic, clinical features and complications are related to the mass effect resulting from the inflammation and fibrosis involved in the pathogenesis of SM. When present, common signs, symptoms, and complications include abdominal pain, weight loss, diarrhea, palpable abdominal mass on examination, bowel obstruction, chylous ascites, and mesenteric vessel thrombosis. Although SM was historically diagnosed predominantly by biopsy, current practice has shifted away from this to computed tomography imaging of the abdomen, given the invasive nature of biopsy. However, certain conditions, including mesenteric neoplasia (lymphoma, metastatic carcinoid tumor, desmoid tumor, mesenteric carcinomatosis), can mimic SM on imaging, and if clinical suspicion is equivocal, a biopsy may be warranted for definitive diagnosis. Asymptomatic patients do not require treatment. For patients with pronounced symptoms or complicated SM, the combination of tamoxifen 10 mg twice daily and prednisone 40 mg daily is the first-line pharmacotherapy; no randomized controlled trial of this regimen has been performed. Rarely, surgery may be necessary in cases of persistent bowel obstruction refractory to medical management. Sclerosing mesenteritis has an overall benign course in most cases, but disease progression and fatal outcomes have been reported.