IS ERYTHROPOIETIN A SURVIVAL FACTOR FOR RED-BLOOD-CELLS

Recombinant human erythropoietin (rhuEPO) therapy has been reported to maintain corrected hematocrit values by increasing the length of red blood cell (RBC) survival. This article presents a controlled study th at assessed the RBC survival before, during, and after termination of prolonged rhuEPO treatment of chronic hemodialysis patients. Two group s of 20 patients were studied. The hematocrit value of each patient wa s below 28 vol%, One group (Group A) was treated with rhuEPO for 1 yr and then treatment was stopped because of the unavailability of the dr ug. The second group (Group B) was treated for 2 yr. Epoetin beta was administered subcutaneously, The initial dose was 20 U per kg body wei ght three times weekly. Upon reaching the target hematocrit value of 3 0 to 35 vol%, the dose was individualized for each patient, to maintai n target range. RBC survival was determined by the chromium-51 techniq ue. In Group A, RBC survival was determined: (1) before, (2) at 12 mon ths, and (3) 1 yr after cessation of rhuEPO treatment. In Group B, RBC survival was determined: (1) at 24 months of therapy, and (2) 1 yr af ter cessation of rhuEPO treatment. RBC survival increased significantl y in both patient groups under rhuEPO treatment, After cessation of th erapy, the RBC survival decreased to pretreatment values. During the c orrection period, reticulocyte counts increased significantly in both groups. Over the maintenance period, they slightly decreased, and afte r termination of rhuEPO therapy, they decreased to the pretreatment va lues, The results of this study could suggest the possibility that RBC survival was prolonged by the action of EPO on the erythroid progenit ors, resulting in the production of RBC with improved viability.