Control of post-transplant erythrocytosis by enalapril.

Abstract

To assess the erythropoietin response in patients with erythrocytosis after renal transplantation who were treated with enalapril. Fourteen patients with stable renal transplants (creatinine clearance, 74.4 +/- 24.6 mL/min) and a packed cell volume of 51% or more over six months and who had no other cause for their erythrocytosis. Patients were treated with enalapril for six months. Serum erythropoietin levels, creatinine clearance and packed cell volume were measured before and during the study; patients were reviewed each month. All patients had erythropoietin levels inappropriate for their packed cell volume. After six months' therapy with enalapril their mean erythropoietin concentration of 21.3 +/- 5.0 U/L fell to 7.4 +/- 1.3 U/L (P < 0.02) although the concentration increased in two patients. The mean packed cell volume fell from 52.7% +/- 0.5% to 44.4% +/- 1.0% (P < 0.0001). There was no change in renal function. Low-dose enalapril controls post-transplant erythrocytosis, at least in part, by lowering serum erythropoietin levels.