Effective removal of leptin via hemodiafiltration with on-line endogenous reinfusion therapy

Leptin is a middle-molecular weight uremic toxin. Hemodiafiltration with on-line endogenous reinfusion (HFR) is a novel dialytic method combining the processes of diffusion, convection and adsorption. We performed a prospective crossover study of patients with end-stage renal disease to investigate the effect of HFR therapy on the level of leptin as compared to conventional low flux hemodialysis (LHD).Eleven stable hemodialysis patients were treated with LHD for 12 weeks and then treated with HFR (SG30 Plus; Sorin Group Italia S.r.1, Mirandola, Italy) for 12 weeks.After 12 weeks of HFR treatment, serum leptin levels significantly decreased (17.1 (2.66 - 39.5) at Week 12 vs. 12.3 (1.80 - 24.3) ng/ml at Week 24, p = 0.014). Although serum adiponectin levels also decreased (1.66 (1.44 - 1.86) at Week 12 vs. 1.12 (0.79 - 1.34) g/ml at Week 24, p = 0.001), the ratio of leptin to adiponectin did not increase after HFR treatment. Serum beta2-microglobulin (beta2M) levels significantly decreased (37.7 (29.8 - 42.6) at Week 12 vs. 28.3 (26.5 - 32.2) mg/dl at Week 24, p = 0.002). Dry weight, Kt/V(urea), normalized protein equivalent of nitrogen appearance, subjective global assessment, and serum albumin levels of the patients were not changed after HFR treatment. There was no difference in the serum levels of C-reactive protein or interleukin-6 between Week 12 and Week 24.The results of our study indicate that HFR may be a better therapy than LHD for removal of middle-molecular-weight uremic toxins such as leptin and b2M.