The effect of dialysis membrane flux on amino acid loss in hemodialysis patients

We examined whether high flux membranes (HF) may induce a greater loss of amino acids compared to low flux membranes (LF). Ten hemodialysis patients participated in this study. Pre- and post-hemodialysis plasma amino acid profiles were measured by reverse-phase high pressure liquid chromatography for both HF and LF. We measured the dialysate amino acid losses during hemodialysis. The reduction difference for plasma total amino acid (TAA), essential amino acid (EAA), and branch chained amino acid (BCAA) was not significantly different in comparisons between the two membranes. (HF vs. LF; TAA 66.85 +/- 30.56 vs. 53.78 +/- 41.28, p=0.12; EAA 14.79 +/- 17.16 vs. 17.97 +/- 28.69, p=0.12; BCAA 2.21 +/- 6.08 vs. 4.16 +/- 10.98 mg/L, p=0.13). For the HF, the reduction in plasma amino acid levels for TAA and EAA were statistically significant. Although it was not statistically significant, the dialysate losses of BCAA were greater than the reduction in plasma (plasma reduction vs. dialysate loss; HF 2.21 +/- 6.08 vs. 6.58 +/- 4.32, LF 4.16 +/- 10.98 vs. 7.96 +/- 3.25 mg/L). HF with large pores and a sieving coefficient do not influence dialysate amino acid losses. Hemodialysis itself may influence the dialysate amino acid losses and may have an effect on protein metabolism.