Erythropoietin and erythropoiesis in renal transplantation

This report reviews the features of erythropoietin (Epo) production after renal transplantation. Successful kidney transplantation leads to the correction of renal anaemia over an 8-10 week period. An early ineffective peak of serum Epo may occur when there is delayed graft function. A late peak follows the decrease in serum creatinine and this is associated with a rise in haemoglobin. Serum Epo returns to normal when the haematocrit reaches 32%. Acute early rejection causes a striking reduction in serum Epo and reticulocytosis. In some patients the haematocrit continues to increase after complete correction of anaemia, resulting in post-transplant erythrocytosis (PTE). PTE generally appears to be an idiopathic erythrocytosis independent of Epo secretion. A greater Epo sensitivity of erythroid progenitors has been suggested. Theophylline and angiotensin converting enzyme inhibitors, which attenuate Epo production, can be used to treat PTE. The second part of this report describes the possible impact of human recombinant Epo (rHuEpo) on renal transplantation. The avoidance of blood transfusion with rHuEpo should eliminate the initiation of anti-HLA sensitization in uraemic patients without previous pregnancy and prior allograft. In some but not all presensitized patients transfusion withdrawal may reduce the sensitization level. There is currently no evidence that the reversing of anaemia by rHuEpo in kidney recipients impairs early graft function. Our results suggest that treatment with rHuEpo prior to transplantation may prevent the appearance of PTE. rHuEPO will reverse anaemia in patients with a failing graft and severe anaemia with little risk of accelerating graft failure and adverse events.