Detlef H. Krieter, Marieke Rüth, Horst-Dieter Lemke, Christoph Wanner

• Introduction Medium-cut-off (MCO) dialyzers may beneficially impact outcomes in patients on hemodialysis. Methods In a randomized, controlled trial in maintenance hemodialysis patients, the new Nipro ELISIO-17HX MCO dialyzer was compared to the Baxter Theranova 400 filter regarding middle molecule removal. Furthermore, the suitability of two assays for free lambda-light chain (λFLC) detection (Freelite vs. N-Latex) was verified. Results ELISIO-HX achieved slightly lower reduction ratios for β2-microglobulin (71.8 ± 6.0 vs. 75.3 ± 5.8%; p =Introduction Medium-cut-off (MCO) dialyzers may beneficially impact outcomes in patients on hemodialysis. Methods In a randomized, controlled trial in maintenance hemodialysis patients, the new Nipro ELISIO-17HX MCO dialyzer was compared to the Baxter Theranova 400 filter regarding middle molecule removal. Furthermore, the suitability of two assays for free lambda-light chain (λFLC) detection (Freelite vs. N-Latex) was verified. Results ELISIO-HX achieved slightly lower reduction ratios for β2-microglobulin (71.8 ± 6.0 vs. 75.3 ± 5.8%; p = 0.001), myoglobin (54.7 ± 8.6 vs. 64.9 ± 8.7%; p < 0.001), and kappa-FLC (62.1 ± 8.8 vs. 56.3 ± 7.7%; p = 0.021). λFLC reduction ratios were more conclusive with the Freelite assay and not different between ELISIO-HX and Theranova (28.4 ± 3.9 vs. 38.7 ± 13.4%; p = 0.069). The albumin loss of Theranova was considerably higher (2.14 ± 0.45 vs. 0.77 ± 0.25 g; p = 0.001) and the Global Removal ScoreLoss alb largely inferior (30.6 ± 7.4 vs. 82.4 ± 29.2%/g; p = 0.006) to ELISIO-HX. Conclusions The new ELISIO-HX expands the choice of dialyzers for MCO hemodialysis.…