Mesenteric panniculitis, also known as mesenteric lipodystrophy, is characterised by non-specific inflammation of the fat in the small bowel mesentery. The aetiology is unclear. It generally occurs in people over 50 years of age. CT classically demonstrates a well-defined halo of increased fat density surrounding the mesenteric vessels without displacing them, and small soft tissue nodules within the halo. It typically extends from the mesenteric root into the left side of the abdomen along the jejunal mesentery. This condition is often asymptomatic and discovered incidentally on abdominal CT, but may cause abdominal pain or fullness, nausea, bowel disturbances or a palpable mass.

Mesenteric panniculitis may have a fibrotic component, believed to represent progression of the disease. In such cases CT shows a solid mesenteric mass that causes distortion of the mesenteric vessels and bowel loops, and uncommonly may cause bowel obstruction. This variant is known as sclerosing mesenteritis or retractile mesenteritis and may mimic carcinoid or desmoid tumour.
There is no treatment unless the bowel is obstructed, and most cases resolve with time.

1. Daskalogiannaki M. et al CT Evaluation of Mesenteric Panniculitis, American Journal of Roentgenology, 2000; 174:427-431
2. Patel N et al. Case of the Day, Radiographics,1999; 19:1083-1085
Credit: Dr Donna D’Souza