Comparison of efficiency of medium molecular weight uremic toxin removal between high-flux hemodialysis and postdilution online hemodiafiltration

Introduction. Conventional high-flux hemodialysis effectively removes uremic toxins of medium molecular weight of 0.5-15 (20) kDa, while postdilution online hemodiafiltration effectively removes uremic toxins of medium molecular weight in the range of 0.5-60 kDa. AIM. The aim of the study was to compare the efficacy of b2-microglobulin removal from the patient serum during a single session of conventional high-flux hemodialysis and postdilution online hemodiafiltration. METHOD. Eighty-five patients treated with conventional high-flux hemodialysis and thirty patients treated with postdilution online hemodiafiltration were examined. The main parameter for assessing the removal efficiency of medium molecular weight uremic toxins was serum b2microglobulin concentration before and after a single session of conventional high-flux hemodialysis and postdilution online hemodiafiltration. The following were used for statistical analysis: Kolmogorov-Smirnov test, Student's T test and Mann-Whitney U test. RESULTS. In patients treated with postdilution online hemodiafiltration, the average total convective volume was 21.38 ± 2.97 liters per session. The b2-microglobulin reduction index for the FX CorDiax 600 dialysis membrane was 61.76 ± 7.32%, while for the FX CorDiax 800 dialysis membrane it was 74.69 ± 6.51%. The albumin reduction index for the FX CorDiax 600 membrane was 3.48 ± 1.28%, and for the FX CorDiax 800 dialysis membrane it was 6.01 ± 2.97%. There is a highly statistically significant difference between the reduction index of b2-microglobulin and albumin, for two different dialysis modalities and two different dialysis membranes (p < 0.01). CONCLUSION. Postdilution online hemodiafiltration is more efficient in removing b2-microglobulin from patient serum, compared to conventional high-flux hemodialysis. Albumin loss during a single session of high-flux hemodialysis is lower compared to a single session of postdilution online hemodiafiltration. With both dialysis modalities, albumin loss is less than 4.0 g/4h. High-flux hemodialysis effectively prevents the development of dialysis-related amyloidosis, while postdilution online hemodiafiltration effectively prevents not only the development of dialysis-related amyloidosis, but also the development of resistance to erythropoietin and atherosclerotic cardiovascular diseases in the population treated with regular dialysis.