Comparable Efficacy of Medium Cut-Off Dialysis plus HA130 Hemoadsorption and Post-filter Hemodiafiltration in Removing Protein-Bound Uremic Toxins

<h2>Abstract</h2><h3>Rationale & Objective</h3> Protein-bound uremic toxins, including indoxyl sulfate and p-cresyl sulfate, are poorly removed by conventional dialysis and contribute to cardiovascular, inflammatory, and neurological complications in end-stage kidney disease. While postfilter hemodiafiltration enhances middle-molecule clearance, its availability is limited. We evaluated whether combining medium cut-off dialysis with HA130 hemoadsorption achieves protein-bound uremic toxins removal comparable to optimized postfilter hemodiafiltration. <h3>Study Design</h3> Prospective, single-center, parallel-group, single-session comparative study. <h3>Setting & Participants</h3> Twenty adult anuric maintenance hemodialysis patients treated at a tertiary dialysis center were allocated to medium cut-off dialysis with hemoadsorption (n=10) or postfilter hemodiafiltration (n=10). <h3>Exposure</h3> Expanded hemodialysis using a medium cut-off membrane combined with HA130 hemoadsorption versus postfilter hemodiafiltration. <h3>Outcomes</h3> Corrected reduction ratios of protein-bound uremic toxins (indoxyl sulfate, p-cresyl sulfate, carboxymethyllysine, protein carbonyls) and middle molecules (β₂-microglobulin, free light chains, prolactin, parathyroid hormone, soluble receptor for advanced glycation end-products). <h3>Analytical Approach</h3> Pre- and post-dialysis plasma concentrations were measured, and corrected reduction ratios values were calculated adjusting for hemoconcentration. Between-group comparisons were performed using nonparametric tests. <h3>Results</h3> Corrected reduction ratios for key protein-bound uremic toxins were similar between medium cut-off dialysis with hemoadsorption and hemodiafiltration. Indoxyl sulfate corrected reduction ratios was 28.0% (IQR 21.6–41.7) with medium cut-off dialysis with hemoadsorption and 26.0% (22.5–37.9) with hemodiafiltration, while p-cresyl sulfate corrected reduction ratios was 31.8% (23.9–37.4) versus 36.5% (23.9–39.7), respectively (all p>0.05). Carboxymethyllysine and protein carbonyl removal did not differ between modalities. In contrast, hemodiafiltration achieved higher corrected reduction ratios for conventional middle molecules, including β₂-microglobulin and free light chains. soluble receptor for advanced glycation end-products reduction was modest and comparable across treatments. <h3>Limitations</h3> Small sample size, single-session design, and reliance on plasma reduction ratios without direct dialysate mass measurements. <h3>Conclusions</h3> In this exploratory study, medium cut-off dialysis with hemoadsorption achieved protein-bound uremic toxins removal similar to optimized postfilter hemodiafiltration, despite lower clearance of conventional middle molecules. Hybrid strategies integrating diffusion, convection, and adsorption may expand protein-bound uremic toxins removal options, particularly where hemodiafiltration is not feasible.