Sclerosing encapsulating peritonitis, previously termed abdominal cocoon, is a rare cause of acute or subacute intestinal obstruction, in which, a part of, or the entire small bowel is encapsulated within a thick fibrocollagenous membrane.

It may be idiopathic, or occur due to chronic peritoneal dialysis, peritoneal shunts, infections like tuberculosis, or gastrointestinal malignancies.

CT is the imaging modality of choice. The characteristic findings are the presence of dilated and thickened small bowel loops pushed to the center of the abdomen, and enclosed within a thick membrane. Other findings include fixation of small bowel loops, ascites and peritoneal calcifications 

The differential diagnosis is an internal hernia, especially with the findings of dilated and fixed small bowel loops, and signs of intestinal obstruction. However, the lack of a membrane encasing the bowel loops helps to rule out this entity.