Effects of recombinant human erythropoietin on sodium balance in nondialysed children with chronic renal failure.

In this study rhEPO, 70 U/kg, was subcutaneously administered two times a week for eight weeks to twelve nondialysed patients with renal anaemia and chronic renal failure. Renal function tests, blood pressure, Hb, Hct, FENa and Na-K-ATPase enzyme activity before and after administration of rhEPO have been studied. We have searched for correlations, if any, between these parameters. After the treatment period mean Hb concentration and mean Hct values increased from 7.5 +/- 0.3 to 8.6 +/- 0.5 g/dl and from 22.5 +/- 1.2 to 26.7 +/- 1.6%, respectively (p < 0.05), whereas no significant differences between pretreatment and posttreatment Cr and CrCl values were found (p > 0.05). No changes in blood pressure were found throughout the study. While mean FENa decreased from 10.2 +/- 1.6 to 6.15 +/- 1.05% (p < 0.05), mean Na-K-ATPase enzyme activities decreased from 0.120 +/- 0.016 to 0.095 +/- 0.025 mumol Pi/h/mg protein (p > 0.05) after treatment. In conclusion, subcutaneous administration of rhEPO, at doses of 70 U/kg twice a week in nondialysed patients increased Hb and Hct values. A significant decrease of FENa was observed after rhEPO treatment and there was no correlation between Na-K-ATPase enzyme activity and FENa.