Protein S deficiency and skin necrosis associated with continuous ambulatory peritoneal dialysis

Skin necrosis associated with protein C deficiency has recently been reported to occur in hemodialysis patients. The clinical presentation and course of this syndrome appears indistinguishable from skin necrosis (purpura fulminans) seen in other settings with inherited or acquired deficiency of the naturally occurring anticoagulant proteins, protein C and S. Patients on maintenance hemodialysis may have low levels of these factors. However, patients on peritoneal dialysis have normal or elevated levels of these proteins despite documented peritoneal losses. We report two patients in whom the occurrence of protein S deficiency and subsequent skin necrosis can be related to demonstrated peritoneal dialysis-associated losses. We suggest that these losses may become critical under appropriate conditions and suggest caution in peritoneal dialysis patients requiring warfarin therapy.