Positive effect of recombinant human erythropoietin on static and dynamic properties of individual red blood cells in uremic hemodialysed children 1

Abstract

The deformability of RBC in uremic hemodialysed children was determined by two different micropipette techniques (apparent elastic shear modulus of RBC membrane µ; entry time t_e and amplitude A) in dependence on the period of rhEPO administration. At the outset, mean hematocrit of the 10 children enclosed in the study was 0.20 +/− 0.02, mean predialysis levels of serum creatinine and urea nitrogen were (919 +/− 163)µMol/l and (24.3 +/− 3.0)mMol/l, respectively. Dialysis was performed with hollow fiber dialyzer three times a week for 4 hours each. Mean µ, t_e and A in children with end-stage renal disease were found to be elevated by 126, 54 and 65 %, respectively, above corresponding mean values of the healthy reference group. Under the therapy with rhEPO mean values of µ, t_e and A were already significantly decreased by 67, 35 and 34 %, respectively, within the correction period (rhEPO dose: 100 IU/kg/week). In the maintenance period of rhEPO therapy (Hct = 0.30 +/− 0.03) the mean values of deformability parameters reached those of the healthy reference group. Mean cell volume of uremic erythrocytes rose significantly under rhEPO administration. This study showed that under rhEPO therapy apart from the desired correction of anemia of end-stage renal disease the impaired rheological properties of uremic RBC will also be normalised. This findings underline that the impaired RBC deformability in hemodialysed uremic patients cannot be attributed to “uremic toxines” alone.