ß-trace protein is highly removed during haemodialysis with high-flux and super high-flux membranes.

ABSTRACT

BACKGROUND: Serum ß-trace protein (ßTP, MW 23-29 kDa) is a marker of GFR impairment in renal patients. Recent papers propose to predict residual renal function (RRF) in maintenance haemodialysis (MHD) patients from serum concentrations of ßTP and other small proteins, avoiding the collection of urine. Few data are available on the removal of ßTP in patients treated with dialysis membranes with different flux characteristics. The aim of this study was to evaluate the effects of haemodialysis with low-flux, high-flux and super high-flux membranes on serum concentrations of ßTP in MHD patients with null RRF. METHODS: Serum ßTP concentrations were measured before and after the first dialysis of the week in 51 MDH patients treated by low-flux (n = 24), high-flux (n = 17), or super high-flux (n = 10) membranes. The removal of ß2-microglobulin (ß2M, MW 11.8), cystatin C (Cys, MW 13.3), urea and creatinine was also analyzed. RESULTS: Low-flux membranes did not remove ßTP, ß2M and Cys whose concentration increased at the end of dialysis. High-flux membrane removed more efficiently ß2M and Cys than ßTP. Super high-flux membrane had the highest efficiency to remove ßTP mean reduction ratio (RR) 53.4%, similar to ß2M (59.5%), and Cys (62.0%). CONCLUSIONS: In conclusion, the plasma clearance of small proteins and particularly of ßTP is dependent from the permeability of the dialysis membranes Therefore, the reliability of the formulas proposed to predict RRF from serum ßTP and other LMWP may be affected by the different permeability of the dialysis membranes.