Sclerosing mesenteritis, a rare mesenteric disorder, in a patient with ulcerative colitis.

A 60-year-old female who had been ill with ulcerative colitis for more than ten years presented with upper abdominal pain. A flare-up of ulcerative colitis was unlikely, because she did not report rectal bleeding, altered bowel habit, and changes of stool form. A poorly defined mass with mild tenderness was palpable in the upper abdomen, with increased levels of serum pancreatic enzymes, leading us to suspect pancreatic disease. Although CT scan revealed no abnormalities in the pancreas, a well-defined, heterogeneous soft tissue mass was found in the small bowel mesentery. Although several different diagnoses were considered, characteristic features on CT strongly supported diagnosis of sclerosing mesenteritis. The symptoms resolved quickly without specific treatment. The mesenteric lesion has never changed and no unfavorable events have yet occurred.