“Abdominal cocoon” small bowel obstruction: a diagnostic challenge in adolescent female

Abstract

Primary sclerosing encapsulating peritonitis (SEP), also referred to as abdominal cocoon syndrome (ACS), is an exceedingly unusual etiology of intestinal obstruction. Morphologically, defined by the entire or partial encasement of the small intestine within a dense fibrocollagenous membrane. Historically it was prevalent among adolescent females in tropical regions. Latest evidence indicates its global distribution, with a higher incidence in males than females. ACS poses a significant diagnostic problem due to its non-specific clinical presentation. We report the case of a 15-year-old female presenting with acute on chronic intestinal obstruction with a history of recurrent similar episodes of abdominal distention with progressive constipation. Preoperative imaging (CECT abdomen) suggested small bowel obstruction with a transition point at the distal jejunum/proximal ileum, without pinpointing on the presence of cocooning. Exploratory laparotomy revealed that the ileal loops were entirely encased in a dense, avascular fibrous peritoneal sac, presenting a classic "cocoon" appearance. Adhesiolysis and excision of the thickened membrane were performed. Histopathology confirmed sclerosing peritonitis with chronic inflammatory infiltrate without evidence of granulomas or tuberculosis affirming that the disease is idiopathic (primary). This case highlights the importance of considering ACS in the differential diagnosis of intestinal obstruction in adolescent females, particularly in tropical regions and demonstrates the curative potential of surgical membrane excision.