Erythrocytosis after renal transplantation. The response to theophylline treatment.

Erythrocytosis was found in 20 out of 127 patients who underwent renal transplantation (15.7%). Four were found to have elevated erythropoietin concentrations (139.7±22.0 μm/ml) and 7 had normal levels (52.3±84 μm/ml (normal -60). The growth of erythroid CFUs was found to be normal in all patients. Theophylline treatment was given to 11 patients. The patients were divided into 3 groups according to their response: (1) patients with high erythropoietin levels whose hematocrit decreased from 59.6% to 46.3% within 2 weeks of treatment in parallel with a fall in erythropoietin; (2) patients with normal erythropoietin levels in whom theophylline therapy reduced the hematocrit from 58.7% to 47.2%; and (3) patients in whom theophylline had no effect on their erythrocytosis