Angiotensin-converting enzyme inhibitor-induced anemia and treatment for erythrocytosis in renal transplant recipients.

Erythrocytosis is not rare in renal transplant recipients, and phlebotomy is still the main treatment. Recently, the occurrence of angiotensin-converting enzyme (ACE) inhibitor induced anemia in patients on chronic hemodialysis and in renal transplant recipients has been reported. We herein report 5 transplant recipients whose hematocrit levels decreased while taking ACE inhibitors, including 2 patients treated with ACE inhibitors for erythrocytosis. The individual mean hematocrit values ranged from 35.0% to 54.7% before treatment and from 27.6% to 42.0% after treatment. The hematocrit level in the 2 patients with erythrocytosis decreased from 54.7% to 39.8% and 47.5% to 27.6%, respectively. Anemia improved after discontinuation or dosage reduction of the drugs. The patients were given the same immunosuppressive drugs, and had good renal function. ACE inhibitor-induced conspicuous anemia was not observed in the transplant recipient who received a kidney from a twin sibling and had not been taking any immunosuppressive drugs, nor in the 8 other patients with diabetes mellitus or chronic glomerulonephritis who served as controls. We conclude that ACE inhibitor-induced anemia may frequently arise in an immunosuppressed state. Based on these events, the ACE inhibitor can be used as a potent drug for erythrocytosis in post-transplant recipients.