Erythrocytosis in patients on long-term hemodialysis.

Erythrocytosis was seen in two men during maintenance hemodialysis therapy for end-stage renal disease secondary to apparent chronic glomerulonephritis. Nonrenal causes of erythrocytosis such as polycythemia vera, chronic hypoxemia, high-oxygen affinity hemoglobin, and hepatoma were excluded by appropriate clinical studies. A computed tomographic scan of the abdomen showed numerous renal cysts in each patient consistent with acquired cystic disease of end-stage kidneys. Peripheral serum erythropoietin levels were elevated as measured by sensitive radioimmunoassay. The findings suggest that the erythrocytosis is caused by an erythropoietic mechanism related to the diseased kidneys. A review of the literature failed to show previous reports of this clinical association.