Idiopathic erythrocytosis in a patient on chronic hemodialysis

A78-year-old man on hemodialysis presented to our hospital with erythrocytosis. He had started hemodialysis 4 years previously, with a hemoglobin level of 9.8 g/dL, and was administered eiythropoiesis stimulating agents and ferrous sulfate. Two years previously, his hemoglobin level increased to 14.5 g/dL and the treatment for anemia was discontinued. He continued hemodialysis thrice weekly; however, the hemoglobin level had increased to 17.0 g/dl at the time of presenting to our hospital. His serum erythropoietin level was 31.4 mlU/mL (range, 3.7-31.5 mlU/mL), carboxyhemoglobin level was 0.6% (range, 0-1.5%), and oxygen saturation in ambient air was 95.4%. The JAK2 V617F mutation was not observed and other bone marrow abnormalities were not identified. The patient was diagnosed with bladder cancer and a transurethral resection was performed. Eight months after the treatment of bladder cancer, his hemoglobin level was 15.1 g/dL, and he was diagnosed with idiopathic erythrocytosis. Copyright (C) 2015. The Korean Society of Nephrology. Published by Elsevier. This is an open access article under the CC BY-NC-ND license.