EFFECTS OF RECOMBINANT-HUMAN-ERYTHROPOIETIN AND CORRECTION OF ANEMIA ON PLATELET-FUNCTION IN HEMODIALYSIS-PATIENTS

To clarify the effects of correction of anemia with recombinant human erythropoietin (r-HuEPO) on the hemostatic defects in uremia, hemostatic parameters were examined in 18 hemodialysis patients with renal anemia. Anemia improved significantly 12 weeks after r-HuEPO therapy (stage II) compared to pretreatment (stage I) and 6 weeks discontinuation (stage III) periods. Platelet count did not change among the three stages, however, mean platelet volume increased significantly at stage II in comparison with stage I. Ivy bleeding time (BT) significantly shortened at stage II and prolonged again at stage III. Although there were no significant changes in platelet aggregation, plasma TxB2, 6-keto-PGF1-alpha, F.VIII:C and F.VIII:Ag levels throughout the study, platelet adhesion and von Willebrand factor (vWf):Ag significantly increased at stages II and III. Augmentations in these parameters were more remarkable in BT-shortened patients (n = 12) than in the BT-unchanged group. These results indicate that correction of anemia with r-HuEPO brought about improvement in uremic hemostatic defect via the increase in red cell volume and vWf:Ag, and new production of platelets, reflected by the improvement in platelet adhesion.