The effects of recombinant human erythropoietin on hemostasis and fibrinolysis in hemodialysis patients.

Thromboembolism might complicate the treatment of patients with chronic renal failure with Recombinant Human Erythropoietin (ReHuEPO). In order to detect prothrombotic changes, a number of hemostatic and fibrinolytic parameters was determined during ReHuEPO treatment of fifteen chronic hemodialysis patients (mean age 47.1 years; ten females, five males). To avoid the influence of hemoconcentration and/or dilution, the patients were kept normovolemic, using the method of echography of the inferior vena cava diameter. In a first group of eight patients, we investigated platelet count and function. During ReHuEPO, a significant rise of hematocrit (19 +/- 3 to 34 +/- 5%, p < 0.001) was observed. Bleeding time shortened (7'33'' +/- 3'39'' to 3'41'' +/- 3'19''; p < 0.001) and platelet count increased (222 +/- 45 to 254 +/- 49 10 9/l; p < 0.005). The initial negative in vitro spontaneous platelet reactivity became positive in two of them, whereas the decrease in ADP threshold in the whole group (2.0 +/- 0.1 to 1.10 +/- 0.4 mumol, p < 0.02) indicated an increased induced platelet reactivity. In all patients prothrombotic changes were observed. The protein-C antigen and protein-C activity and the total and free protein-S antigen decreased significantly. The plasminogen activator inhibitor (PAI) activity in the whole group did not change significantly (6.4 +/- 4.1 to 5.4 +/- 4.8 AU/ml). However, in the patients with fistula thrombosis (n = 3), higher values in all test points were found compared to those without thrombosis.