Pathology of encapsulating peritoneal sclerosis. Perit Dial Int 2005; 25(Suppl 4):S19–29. by guest on February 26, 2014 http://w w w .pdiconnect.com / D ow nloaded from

Pathology findings of encapsulating peritoneal sclero-sis (EPS) are reviewed to establish histologic criteria for a diagnosis of EPS. The typical macroscopic finding is a co-coon-like encapsulation of the entire intestine. This encap-sulation is frequently accompanied by fibrin deposition, focal bleeding on the peritoneum, and various quantities of bloody ascites. A thin membrane on the visceral perito-neum contributes to the formation of the intestinal encap-sulation. Histologically, the membrane is composed mainly of organized fibrin, probably derived from plasma exuda-tion from the peritoneal microvasculature. The peritoneal fibroblasts appear swollen and exhibit an increased level of cellularity, accompanied by expression of various acti-vation and proliferation markers. According to the “two-hit” theory of EPS pathogenesis, deterioration of the perito