What is sclerosing encapsulating peritonitis, and what are its CT and MR imaging features?
Sclerosing encapsulating peritonitis is a rare but severe condition characterized by progressive peritoneal fibrosis, inflammation, calcification, and vascular alterations, with partial or total encasement of the small bowel. It is multifactorial in etiology but is most commonly associated with chronic ambulatory peritoneal dialysis. Often, one portion of the abdomen is more affected than others, forming a mass or “abdominal cocoon” usually containing small bowel loops and ascites. This condition generally has a poor prognosis due to bowel obstruction, malnutrition, septicemia, or postoperative complications.
Very high attenuation and very low signal intensity visceral and parietal peritoneal surfaces are seen due to peritoneal calcification or ossification. Diffuse smooth peritoneal thickening, peritoneal enhancement, loculated ascites, and adherent dilated loops of small bowel, sometimes with gas-fluid levels and wall thickening, may also be seen.