Comparison of four medium cut-off dialyzers

Lay Summary The pharmaceutical industry has developed new membranes with a bigger and more tailored pore diameter, called medium cut-off dialyzers, the characteristics of which differ from others to the point that they have generated a new dialysis modality, expanded hemodialysis. This study aimed to assess the clinical efficacy and safety of four new medium cut-off dialyzers (Phylther 17-SD, Vie-18X, Elisio HX19 and Theranova 400 dialyzers) compared against each other and with other dialysis modalities-high-flux hemodialysis and post-dilution hemodiafiltration. The reduction ratios of solutes between 60 and 60 000 Da were measured. Safety was evaluated with albumin loss. The results show that all four medium cut-off filters obtained similar results regarding different molecular weight molecules, reduction ratios and albumin loss. And also, expanded hemodialysis has better efficacy than high-flux hemodialysis but is still inferior to hemodiafiltration, without safety concerns. Background Recently, several pharmaceutical companies have developed new medium cut-off (MCO) dialyzers for expanded hemodialysis (HDx). This study aimed to compare the safety and efficacy of four MCO dialyzers, against each other and versus high-flux hemodialysis (HD) and post-dilution hemodiafiltration (HDF). Methods A prospective study was carried out on 23 patients who underwent six dialysis sessions: two sessions with the FX80 Cordiax in HD and HDF, and four HDx sessions with the Phylther 17-SD, Vie-18X, Elisio HX19 and Theranova 400 dialyzers. The reduction ratios (RRs) of urea, creatinine, beta(2)-microglobulin, myoglobin, kappa free immunoglobulin light chain (kappa FLC), prolactin, alpha(1)-microglobulin, alpha(1)-acid glycoprotein, lambda (lambda FLC) and albumin were compared. Dialysate albumin loss was also measured. Results The differences in efficacy between the evaluated dialyzers were minimal in small molecules and even up to the size of beta(2)-microglobulin. The main differences were found between myoglobin, kappa FLC, prolactin, alpha(1)-microglobulin and lambda FLC RRs, in which all four MCO dialyzers, with similar efficacy, were clearly superior to HD and slightly inferior to HDF treatment. Albumin losses in the dialysate with HD dialyzers were <1 g and between 1.5 and 2.5 g in HDx and HDF. The global removal score values were similar in all four HDx treatments, and again significantly higher than those with HD. Conclusions The results of the four MCO dialyzers evaluated in this study showed good efficiency, with no significant performance differences between them while being completely safe in terms of albumin loss. Likewise, the study confirms the superiority of HDx over high-flux HD with an efficacy close to that of post-dilution HDF.