抄録
A 10-year-old girl with erythrocytosis is reported. She had occasional mild headache and nausea from three years old. Erythrocytosis was noticed at the age of ten when she first visited the outpatient clinic of the Pediatric Department of Hirosaki University because of upper respiratory infection. The routine laboratory studies showed red blood cell count of 755×104/mm3, hemoglobin of 22.1 g/dl, and hematocrit of 70%. Erythropoietin activity in the plasma was found to be an upper limits of the normal control. But it rose twice at 24 hours after phlebotomy. Subsequent investigations failed to support the diagnosis such as polycythemia vera, secondary polycythemia due to hypoxia, ectopic erythropoietin production and abnormal hemoglobin. Although there was no evidence of erythrocytosis in the family, the findings in this patient appear to be those of a condition which has been called benign familial erythrocytosis. She has been followed for more than 6 years, but no complications has developed and is living in a healthy normal life.
