Porphyrias: clinical evaluation and interpretation of laboratory tests

Treatment of porphyria cutanea tarda with phlebotomy in a patient on peritoneal dialysis

Porphyria cutanea tarda (PCT) is frequently described among patients with chronic renal failure undergoing hemodialysis. One patient who was receiving peritoneal dialysis and had PCT develop has been described in the literature. However, it was later determined that the patient's PCT was related to the hepatotoxic drug she was receiving rather than her peritoneal dialysis. Our patient is the first reported case, to our knowledge, of a patient with end-stage renal disease with negative hepatitis serology who was not receiving a hepatotoxic drug, or on hemodialysis, who had PCT develop while receiving peritoneal dialysis.

Pure red cell aplasia associated with hepatitis C infection

We report the case of a 34-year-old woman with recurrent pure red cell aplasia and evidence of hepatitis B and C infection. Review of the English literature identified 19 prior cases in which pure red cell aplasia was associated with hepatitis. This case is the first in which serologic evidence of hepatitis C infection was documented. This patient also had porphyria cutanea tarda and marked hepatic siderosis but no active hepatitis or cirrhosis. Treatment with cyclophosphamide and prednisone produced complete remission of the pure red cell aplasia. Erythroid colony formation (colony-forming unit-erythroid and erythroid burst-forming unit) was reduced in cultures of bone marrow obtained during relapse but was normal in remission marrow. However, addition of the patient serum, whether collected during relapse or remission, inhibited erythroid colony formation by her bone marrow. These observations, and the known extrahepatic immunologic manifestations of hepatitis C infection, suggest that the pure red cell aplasia occurred because of autoimmune mechanism provoked by the infection.