Background: Uraemic pruritus (UP) is one of the most common problems in patients with chronic renal failure. Owing to the complexity of UP, no specific treatment is currently available. Recently, the accumulated toxins of mid and macro molecules in advanced renal failure have been proposed to play an important role in the mediation of pruritus.
Aim: To evaluate the effect of high permeability haemodialysis (HPHD) against conventional haemodialysis (CHD) on UP.
Methods: A randomized, prospective, double-blind study was performed to compare the efficacy of HPHD against CHD in the treatment of UP. In total, 116 patients with chronic renal failure and UP were enrolled in the trial. A visual analogue scale (VAS) was used to assess the severity of itch. The toxins of mid and macro molecules [beta2-microglobulin (beta2-MG), parathyroid hormone (PTH), respectively] were measured, and the solute clearance rate (SCR) and urea clearance index (Kt/V) were also determined.
Results: The pruritus scores in the HPHD group were significantly lower (2.23 +/- 1.05) than those in the CHD group (5.45 +/- 1.91, P = 0.012), although the SCR and Kt/V showed no significance between the two groups (SCR P = 0.075; Kt/V P = 0.082). It was found that HPHD and CHD achieved a reasonable clearance rate of blood urea nitrogen and creatinine. However, the toxins of mid and macro molecules were markedly reduced in the blood of patients treated with HPHD, compared with those treated with CHD. The concentrations of PTH and beta2-MG were significantly reduced by HPHD in comparison with CHD (PTH 119.27 +/- 8.41 vs. 165.18 +/- 9.37 pmol/L, P = 0.01; beta2-MG 3.39 +/- 0.76 vs. 5.92+/- 1.58 g/mL, P = 0.012).
Conclusions: These data indicate that HPHD can efficiently relieve UP through clearance of accumulated mid and macro molecules in vivo. This further supports the hypothesis that these molecules are involved in UP.