Erythrocytosis induced by danazol in an anephric patient.

A white woman with end stage renal failure due to reflux nephropathy started regular haemodialysis in 1972 when aged 17. Both kidneys were removed in 1973 because of persistent infection and hypertension; this led to severe anaemia, which was exacerbated by occult bleeding from a gastric ulcer. She transferred from haemodialysis to continuous ambulatory peritoneal dialysis in 1982 but remained anaemic with a haemoglobin concentration of 45-65 g/l, and by 1983 had developed iron overload from multiple transfusions (serum ferritin concentration >5000 [tg/l). In 1983 her transfusion requirement was increased by menorrhagia; this failed to respond to norethisterone and in October 1984 she started danazol 400 mg daily. During the next four months her menstrual loss was completely suppressed, but she became depressed, lethargic, and increasingly obese. In February 1985, after a short illness with headache, loss of concentration, and pruritus, she developed a dense right sided hemiparesis. Her haemoglobin concentration was 179 g/l; this increase was not due to haemoconcentration as there was no clinical evidence of fluid depletion. The blood film and bone marrow aspirate gave no evidence of a primary myeloproliferative disorder. She died five days later, and necropsy showed a brain stem haemorrhage and moderate iron deposition in the liver but no recognised cause of secondary polycythaemia. The serum immunoreactive erythropoietin concentration at the time of her final admission was 56 mIU/ml (range for normal blood donors 13-37 mIU/ml); this was indistinguishable from renally derived erythropoietin, as shown by parallel dose response curves of the patient's serum, normal sera, and the international reference preparation of erythropoietin.