Effects of long-term erythropoietin therapy on fibrinolytic system in haemodialyzed patients.

INTRODUCTION

Recombinant human erythropoietin (rHuEPO) is the cornerstone of anaemia therapy in uraemic patients however the effects of this hormone on fibrinolytic system are difficult to interpret.

MATERIALS AND METHODS

Assessment of fibrinolytic parameters: tissue-type plasminogen activator (tPA) antigen, urokinase-type plasminogen activator (uPA) and its soluble receptor (suPAR), plasminogen activator inhibitor 1 (PAI-1) and plasmin/antiplasmin (PAP) complexes were performed in haemodialyzed (HD) patients without rHuEPO therapy: Group I (n=8, Hg<10 g/dl); Group II (n=12, Hg>10 g/dl); and in HD patients treated with rHuEPO for more than 6 months (Group III, n=10) or for more than 12 months (Group IV, n=9) in relation to the healthy controls.

RESULTS

Patients of Group I had the significantly lower haematological parameters than those of Groups II, III and IV. All the fibrinolytic parameters studied, except PAI-1, were significantly higher in HD patients without rHuEPO therapy when compared to the controls. There were no significant differences in fibrinolytic system between the Groups I and II. Erythropoietin therapy resulted in progressive decrease in antigenic tPA levels, which reach normal range values after 6 months rHuEPO administration. uPA and PAP concentrations were also decreased and reached normal values after 12 months of rHuEPO therapy. In these patients a significant decrease in uPAR levels was also observed. Therapy with rHuEPO did not alter PAI-1 concentrations in HD patients.

CONCLUSIONS

These results suggest that long-term rHuEPO therapy can correct fibrinolytic parameters in patients undergoing regular HD irrespective from haemoglobin levels and in the absence of concomitant iron supplementation.