Acquired type II protein C deficiency in a long-term hemodialysis patient

We present a 57-year-old man with end-stage renal failure due to chronic glomerulonephritis, who had been on hemodialysis for 13.5 years and had suffered from recurrent painful swelling of the left leg for 4.7 years. A diagnosis of deep venous thrombosis was made by the phlebography. Coagulation studies showed decreased protein C activity despite a normal protein C antigen level. None of his relatives had decreased protein C activity, and the levels of the other coagulation factors synthesized by the liver were all normal. Accordingly, the patient was diagnosed as having acquired type II protein C deficiency.