Cryptogenic Multifocal Ulcerating Stenosing Enteritis (CMUSE) in a Patient with Down Syndrome: A Case Report.

Background and Clinical Significance: Cryptogenic multifocal ulcerating stenosing enteritis (CMUSE) is a rare idiopathic disorder of the small bowel which remains diagnostically challenging because it can closely mimic Crohn's disease, celiac disease, and non-steroidal anti-inflammatory drug (NSAID)-induced enteropathy; Case Presentation: We report a 44-year-old man with Down syndrome, Hirschsprung's disease, celiac disease, and multiple prior abdominal operations who developed recurrent small-bowel strictures of uncertain cause. Initial management involved endoscopic assessment and jejunal dilatation, but this became neither technically feasible nor durable as the disease progressed. He therefore underwent exploratory laparotomy with small-bowel resection to relieve obstruction and to obtain adequate tissue for diagnosis. On balance, the presence of multifocal ulceration, recurrent mucosa-predominant strictures, and non-transmural jejunitis supported a diagnosis of CMUSE; Conclusions: This case highlights the rarity and diagnostic difficulty of CMUSE, which may closely resemble Crohn's disease in patients with recurrent small-bowel strictures and obstructive symptoms. Early and ongoing MDT coordination (surgery, gastroenterology, radiology, dietetics, and infectious diseases) supports anatomy definition, complication control, and coherent long-term management focused on function and quality of life.