RESUMO
Hemodiafiltration with endogenous reinfusion (HFR) after ultrafiltrate passage through a resin cartridge combines adsorption, convection, and diffusion. Our prospective single-center crossover study compared HFR and online-hemodiafiltration (OLHDF) effects on two uremic toxins and 13 inflammatory, endothelial status, or oxidative stress markers. After an 8-week run-in period of high-flux hemodialysis, 17 eligible stable dialysis patients (median age 65 years, 10 male) without overt clinical inflammation were scheduled for four 8-week periods in the sequence: HFR/OLHDF/HFR/OLHDF. Relative to OLHDF, HFR was associated with greater indoxyl sulfate removal and lesser abnormalities in all other study variables, namely circulating interleukin-6, tumor necrosis factor-alpha, proportions of activated proinflammatory (CD14+CD16+, CD14++CD16+) monocytes, endothelial progenitor cells, apoptotic endothelial microparticles, vascular endothelial growth factor, vascular cellular adhesion molecule, angiopoietins 2 and 1, annexin V, and superoxide dismutase. Differences were significant (P < 0.05) in median values of 13/15 variables. Study period comparisons were generally consistent with dialysis technique comparisons, as were data from the subgroup completing all study periods (n = 9). Our investigation provides hypothesis-generating results suggesting that compared with OLHDF, HFR improves protein-bound toxin removal, inflammatory and endothelial status, and oxidative stress.