Erythropoietin therapy may retard progression in chronic renal transplant dysfunction

Background. Recent data suggests that erythropoietin therapy may actually retard the progression of chronic kidney disease (CKD). Transplant recipients with evidence of chronic allograft dysfunction could respond in a similar manner to erythropoietin. Methods. We evaluated 166 individuals who initiated erythropoietin therapy after at least 18 days of transplant function. One hundred and nine individuals received erythropoietin between days 18 and 294 of transplant function (group I-early epoietin alfa) while 57 individuals received erythropoietin on or after day 294 of transplant function (group 2-late epoietin alfa). The slope of serum creatinine (Scr) (Deltaslope Scr) prior to and following the start of erythropoietin therapy and calculated glomerular filtration rates (GFR) were used to assess renal function over time. Results. The average haematocrit rose 6.6% in group I patients and 2.1% in group 2 patients during the first 100 days of erythropoietin therapy. The Deltaslope Scr was not significantly altered in group I patients. However, for group 2 individuals who continued to have graft function (n=35), the Deltaslope Scr became negative during erythropoietin treatment. This indicated a deceleration in the rate of loss of renal function (day 200 Deltaslope Scr -0.0033, P=0.00091; day 300 Deltaslope Scr -0.0014, P=0.05; day 400 Deltaslope Scr -0.0066, N.S., P=0.066). GFR remained stable in both cohorts. Finally, group 2-late epoietin alfa patients treated with erythropoietin demonstrated a marked trend towards longer graft survival than a group of similar control patients (N.S., P=0.064). Conclusions. The data in a group of renal transplant recipients with chronic allograft dysfunction reinforce data from the CKD realm suggesting that erythropoietin may be of benefit in slowing the rate of loss of function over time. However, this renal response is not evident in all patients. Prospective studies of erythropoietin or erythropoietin-like medications are warranted in this population to better discriminate those who may respond well to administration of these drugs.