EVOLUTION OF PANEL REACTIVE ANTI-HLA CYTO TOXIC ANTIBODIES (PRA) IN PATIENTS ON DIALYSIS (D) TREATED WITH ERYTHROPOIETIN (EPO)

The aim of this study is to observe the effect of EPO and the correspo nding decrease in transfusion (tr) requirements on the percentage of P RA (% PRA) in presensitized patients on D. We have studied PRA every 3 months during 3 years, in 42 patients on D and waiting for transplant ation (Tx), who began treatment with EPO, 24 women and 18 men, mean ag e 37 (20-58) years, with a mean time on D of 7 +/- 3.8 (2-17) y. Patie nts have received a mean of 18.7 tr. Immunisation occurred after previ ous Tx in 16 patients, 1 during pregnancy and only after blood tr in 2 5. Peak PRA was > 75 % in 9 patients. Blood tr requirements with EPO t reatment decreased from a mean of 0,7 +/- 1 tr/month to 0,3, 0,2, 0 tr /m. % PRA declined from 24.2 +/- 26.8 % to 8.9 +/- 18.8 %, p < 0.01. T his change was slow and became significant 9 months after beginning EP O therapy. Cytotoxic Antibodies (CA) induced by Tx declined less and l ater than CA induced by tr, from 35.4 % prior to EPO to 18.1 %. Patien ts with Monospecific CA began with lower CA levels than Bi and Multi-s pecific CA and declined significantly. These changes have ultimately l ed to a decrease in the waiting time for a renal allograft in polytran sfused patients and a decrease in the proportion of highly presensitiz ed patients, PRA > 75 %. Sixteen out of 42 EPO patients were transplan ted, these patients have a graft survival rate better than the 48 othe r patients transplanted during the same period, p < 0.05 at 1 year. EP O treatment of anemia of patients on D reduced % PRA and increase the chance of receiwing a graft. This effect is lower in highly sensitized previously transplanted patients.