Anemia after kidney transplantation.

Over the last years, the renal transplant community has shown a growing interest in the incomplete correction of anemia by the transplanted kidney. Between 25% and 30% of these patients will be anemic at some time after transplantation. In addition to impaired kidney function, other factors may also play a role in the pathogenesis of posttransplant anemia: immunosuppressive agents such as azathioprine, mycophenolate mofetil, and sirolimus; angiotensin-converting enzyme inhibitors and angiotensin-II receptor antagonists; impaired iron homeostasis; and donor and recipient age. There is a controversy on whether posttransplant anemia has the same negative effects on morbidity and mortality as in nontransplanted patients with chronic kidney disease and data on whether correction of anemia are beneficial or lacking. Anemia check-up should be part of the long-term follow-up of the renal transplant patients. Controlled trials should investigate the impact of a better control of anemia on the patient morbidity and outcome.