Sclerosing encapsulating peritonitis or abdominal cocoon is a rare cause of small bowel obstruction characterized by formation of a thick walled sac or "cocoon". The wall of this cocoon is a thick fibrotic membrane and it contains small bowel loops, mesentery and some fluid. Internal adhesions are inevitable. Earlier it used to be an incidental or unsuspected finding during laparotomy but can be diagnosed pre-operatively with high degree of suspicion.

Classification

• idiopathic: usually seen in adolescent females or young adults, usually in tropical and subtropical countries
• secondary: following tuberculosis, widespread peritonitis, intestinal perforation, prior abdominal surgery or ambulatory peritoneal dialysis for long duration

Pathology

It is characterized by formation of a thick fibrotic membrane, encasing adherent small bowel loops and forming a sac or cocoon like mass. This is results in small bowel obstruction.

Presentation

• palpable abdominal mass
• acute or subacute small bowel obstruction
• weight loss, nausea, vomting and anorexia

Management

Surgery is the treatment of choice and involves membrane dissection and adhesiolysis. Resection of non viable bowel loop can be done.

For a complete discussion on this topic please see: sclerosing encapsulating peritonitis.