Expanded hemodialysis is a method of treatment to replace kidney function, which effectively removes uremic toxins of middle molecular weight from the blood of the patients with the end stage of chronic kidney disease. Two basic principles of removing uremic toxins during an expanded hemodialysis session are diffusion and convection. The basis of diffusion is the concentration gradient, and the basis of convection is internal filtration (covective transport). Increased MCO membrane sieving capacity and high internal filtration provide high clearance of middle molecular weight uremic toxins. Expanded hemodialysis prevents the development of microinflammation, malnutrition, resistance to the action of erythropoietin, amyloidosis, accelerated atherosclerosis and atherosclerotic cardiovascular diseases in the population of patients treated with regular dialysis. The task of the nephrologist is to evaluate different dialysis modalities that are available and to select the optimal dialysis modality for the treatment of each patient individually, i.e., the individualization of dialysis treatment.

Objective. The aim of this study was to examine the effect of expanded hemodialysis on the degree of b2-microglobulin removal. Methods. Sixteen patients treated with extended MCO hemodialysis were examined. The main parameter for assessing the efficiency of removal of uremic toxins of middle molecular weight is the concentration of b2-microglobulin in the serum before and after a single session of extended MCO hemodialysis. The following were used for statistical analysis: Kolmogorov-Smirnov test, Student's T test for bound samples and Wilcoxon test. Results. Extended MCO hemodialysis effectively removes uremic toxins of middle molecular weight. The reduction index of b2-microglobulin during a single session of extended MCO hemodialysis is 70.60 ± 5.88%. The average loss of albumin during a single session of extended MCO hemodialysis is 1.88 ± 1.02 g/4h, and the index of albumin reduction is 4.94 ± 2.49%. Conclusion. Extended MCO hemodialysis effectively removes b2-microglobulin. The b2-microglobulin reduction index is ~ 71% and the albumin loss is less than 4.0 g/4h. This dialysis modality prevents the development of amyloidosis, atherosclerosis and atherosclerotic cardiovascular diseases in the population of patients treated with regular hemodialysis.

Introduction/Objective. Accumulation of middle molecular weight uremic toxins causes various complications in chronic hemodialysis (HD) patients. Postdilution online hemodiafiltration (OL-HDF) efficiently removes these molecules. This study aimed to assess the effectiveness of three different dialysis membranes in removing ?2- microglobulin (b2m) within a single session of postdilution OL- HDF. Method. A prospective single-center study was carried out in 30 patients (23 males and 7 females, average age 54.87 ? 11.66 years, time on dialysis 4.95 ? 5.40 years) on maintenance HD. Each patient was followed for 3 consecutive weeks on OL-HDF with three different dialyzers: DiacapPro 19H, FX CorDiax 800, and Elisio 21H, randomly switched weekly. The reduction ratios (RR) of ?2m and albumin were compared individually. Results were analyzed with the Kolmogorov-Smirnov test, ANOVA, and the Kruskal-Wallis test. Results. The average convective volume for all patients was 21.38 ? 2.97 L/session. ?2-m RR was 70.86 ? 6.87%, 74.69 ? 6.51% and 70.04 ? 9.37% with Diacap Pro 19H, FX CorDiax 800 and Elisio 21H membrane respectively (p = 0.054). Albumin RR was 6.20 ? 2.12% with Diacap Pro 19H membrane, 6.01 ? 2.97% with FX CorDiax 800 membrane, and 6.46 ? 2.91% with Elisio 21H membrane (p = 0.812). Albumin loss was < 4.0g/dialysis treatment for all membranes. Conclusion. All investigated membranes effectively remove ?2-m in postdilution OL-HDF with a tolerable albumin loss. The highest ?2-m RR was determined for FX CorDiax 800 membrane, but with no statistically significant difference.

BACKGROUND: Postdilution online hemodiafiltration (OL-HDF) effectively removes uremic toxins of middle molecular weight from the blood of patients with end-stage chronic kidney disease. The rate of removal of uremic toxins depends on the type of dialysis membrane, blood flow rate (Qb), net ultrafiltration flow rate (Qnuf), and total convective volume (Vconv). AIM: The aim of this study was to examine the efficacy of asymmetric triacetate cellulose dialysis membrane in patients on post-dilution OL-HDF. METHODS: Thirty-five patients treated with post-dilution OL-HDF hemodiafiltration for at least 3 months were examined. The main parameters for assessing the efficiency of removal of uremic toxins of middle molecular weight are the concentration of β2-microglobulin (β2-M) and interleukin-6 (IL-6) in serum before and after a single session of post-dilution OL-HDF. The followings were used for statistical analysis: Kolmogorov–Smirnov test, Student’s T test for bound samples and Wilcoxon test. RESULTS: The average Vconv was 20.90 ± 3.30 liters/session. The β2-M reduction index during a single session of postdilution OL-HDF was 71.10 ± 6.39%, the IL-6 reduction index was 43.75 ± 15.60%, and the albumin reduction index was 4.55 ± 2.31%. CONCLUSION: The asymmetric triacetate cellulose dialysis membrane effectively removes β2-M and IL-6 during a single session of postdilution OL-HDF. The β2-M reduction index is ∼70%, the IL-6 reduction index is ∼40%, and albumin loss is <4.0 g/4 h. The examined dialysis membrane and dialysis modality prevent the development of amyloidosis associated with dialysis, microinflammation and reduce the risk of developing atherosclerotic cardiovascular diseases in the population of patients treated with regular 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.