Sclerosing Mesenteritis: Multidisciplinary Collaboration Is Essential for Diagnosis and Treatment.

Sclerosing mesenteritis (SM) is an extremely rare disease characterized by chronic non-specific inflammation, fat necrosis and fibrosis of the mesentery. We presented a 77-year-old man with progressive dyschezia, abdominal pain and mass in left lower quadrant. Computed tomography (CT) exhibited a thickened mesentery, enlarged lymph nodes and strand-like densities around the mesenteric vessels. However, laboratory investigation, colonoscopy and positron emission tomography did not provide any specific results for diagnosis. Because of the exacerbating abdominal pain, partial colectomy was performed and SM was diagnosed based on the pathological changes of mesentery including fat necrosis, multifocal lipid-filled macrophages, lymphocytes and multifocal fibrosis. Although SM is difficult to diagnose and often found by incident, progressive deterioration of abdominal symptoms and general status alteration are indicators of SM. Some typical imaging and pathologic manifestations are also helpful to SM diagnosis. There is no standard treatment for SM. Operation is preferred in those at the stage of fibrosis and particularly combined with intestinal obstruction. Therefore, a multidisciplinary collaboration is essential to diagnose and manage this rare disease, with combined approaches in gastroenterology, colorectal surgery, pathology and radiology.