Posttransplant erythrocytosis in renal transplant recipients at Jeddah Kidney Center, Kingdom of Saudi Arabia.

Abstract Posttransplant erythrocytosis is a well-known complication of renal transplant. It is a persistently elevated hematocrit level equal to or greater than 51%, or a hemoglobin level equal to or greater than 16 g/L, or both, in the absence of other causes. We retrospectively reviewed this complication in patients who had received a renal transplant at our center between January 1991 and December 2005. Of 1655 renal transplant recipients, 159 patients (9.6%; 154 men, 5 women; mean age, 42 +/- 9 years) developed posttransplant erythrocytosis. The mean follow-up was 96 +/- 4 months. Posttransplant erythrocytosis appeared at an average of 8.2 +/- 5 months after transplant (range, 3-40 months) and lasted an average of 10.3 +/- 3 months (range, 7-35 months). In all 159 patients, the immunosuppressive medication regimen included prednisolone; in 144, cyclosporine was used, and in 108 patients, azathioprine was used, while in another group of patients, the latter 2 were changed to mycophenolate mofetil (n=38) and tacrolimus (n=13). Twenty-four patients (15%) were treated with phlebotomies, while 29 patients (18.2%) were given angiotensin-converting enzyme inhibitors. One hundred six patients were left untreated including 92 patients (57.9%) who received prophylactic anti-platelet medications. Remission of posttransplant erythrocytosis was seen in all treated and untreated patients. No thromboembolic complications occurred. Only 9 patients (5.7%) developed chronic allograft nephropathy during follow-up. Our findings suggest that posttransplant erythrocytosis is a benign condition affecting males more than females, usually manifesting in the first year after transplant. Remission of posttransplant erythrocytosis can be seen in all patients; however, some patients may require treatment with phlebotomy or angiotensin-converting enzyme inhibitors. Posttransplant erythrocytosis has no adverse effects on renal graft function.