Systemic calciphylaxis was associated with significantly reduced functional protein C activity compared to control groups (p<0.01), suggesting a role for acquired protein C deficiency.
Observational (n=33)
Is functional protein C deficiency associated with systemic calciphylaxis in patients with end-stage renal disease?
Functional protein C deficiency may contribute to hypercoagulability and thrombosis, resulting in skin necrosis and digital gangrene in systemic calciphylaxis.
p-value: p=<0.01
PURPOSE: To determine if the natural anticoagulant protein C plays a role in the pathogenesis of systemic calciphylaxis, a syndrome characterized by extensive vascular and soft tissue calcification and skin necrosis, which is similar to that seen in warfarin-induced skin necrosis. PATIENTS AND METHODS: The study population included five patients with end-stage renal disease and systemic calciphylaxis undergoing hemodialysis, 12 patients without evidence of calciphylaxis undergoing dialysis, eight patients with nephrotic syndrome, and eight normal healthy volunteers. Protein C antigen levels were measured by rocket immunoelectrophoresis, and functional activity was quantitated by a chromogenic assay and an anticoagulant assay utilizing the venom of Agkistrodon contortrix. RESULTS: Skin biopsy specimens of involved areas in three patients showed thrombotic occlusion of venules identical to that seen in warfarin-induced skin necrosis. Protein C antigen levels were normal in all groups. However, protein C activity was significantly reduced as measured by chromogenic (p less than 0.01) or anticoagulant assays (p less than 0.01) in patients with calciphylaxis compared with the other three groups. CONCLUSION: These findings suggest that hypercoagulability due to functional protein C deficiency may contribute to thrombosis, resulting in skin necrosis and digital gangrene in systemic calciphylaxis.
Mehta et al. (1990) conducted an observational in Systemic calciphylaxis (n=33). Systemic calciphylaxis vs. Dialysis patients without calciphylaxis, nephrotic syndrome patients, and healthy volunteers was evaluated on Protein C functional activity measured by chromogenic or anticoagulant assays (p=<0.01). Systemic calciphylaxis was associated with significantly reduced functional protein C activity compared to control groups (p<0.01), suggesting a role for acquired protein C deficiency.