The effect of hemodiafiltration with on-line endogenous reinfusion (on-line HFR) on anemia: design of a European, open, randomised, multicentre trial

The lack of backfiltration reduces plasma levels of C-reactive protein and interleukin-6. Paired filtration dialysis is the hemodialfitration techniqu e that abolishes backfiltration. By physically separating convection from d iffusion, it allows pure ultrafiltrate to be available during the entire se ssion, so the ultrafiltrate can be regenerated and used as infusion fluid. On these premises, we have developed a European, open, randomised, multicen tre study aimed at evaluating the effect of hemodiafiltration with on-line endogenous reinfusion (on-line HFR) on anemia. At least 130 chronically ure mic hemodialysed (bicarbonate hemodialysis) stable patients with mild anemi a (Hb between 9 and 11 g/dL) will be enrolled and normalized for iron store s by concomitantly repleting iron deposits (if ferritin <300 mu g/L) and re ducing the dose of erythropoietin to maintain Hb values within the range at enrollment (9-11 g/dL). Patients will be included in the study, randomized to the two treatments (test treatment: online HFR; control treatment: hemo diafiltration or modified forms) and followed up for nine months. Iron stor es will be maintained within normal levels and the dose of erythropoietin w ill be kept constant. The primary question and response variable will be th e mean monthly changes in hemoglobin levels over the period of nine months. As secondary questions and response variables, we will measure the nutriti onal status using a subjective global assessment, protein catabolic rate, u rea generation rate and the dietician's assessment, serum concentrations of vitamins A, C, E and serum C-reactive protein.