Acute effect of hemodialysis on serum levels of the proinflammatory cytokines

CHRONIC inflammation is a common feature of end-stage renal disease, which carries a heightened risk of atherosclerosis and other co-morbid conditions. Dialysis treatment per se can bring additional risk factors for inflammation, such as increased risk of local graft and fistula infections, impure dialysate or bio-incompatible membranes. Our study was designed to determine whether a hemodialysis session leads to an acute substantial alteration in the plasma levels of the proinflammatory cytokines interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α, the T-lymphocyte activation factor soluble IL-2 receptor (sIL-2R), and an inflammation mediator and chemotactic granulocyte factor, IL-8, in end-stage renal disease patients receiving chronic intermittent HD. In this study, 21 (12 male/nine female) patients undergoing chronic hemodialysis were enrolled. The acute effect of a hemodialysis session on serum cytokine concentrations was assessed by comparison of pre-hemodialysis and post-hemodialysis determinations. Serum IL-1β, sIL-2R, IL-6, IL-8 and TNF-α levels were determined with chemiluminescence enzyme immunometric assays. A significant difference was not observed for IL-1β, IL-6, TNF-α, and sIL-2R concentrations in pre-hemodialysis and post-hemodialysis specimens (p > 0.05). Serum median (25th-75th percentiles) IL-8 concentration was 69.4 (34.9-110.3) pg/ml before hemodialysis, and decreased to 31.5 (18.0-78.8) pg/ml following hemodialysis (p: 0.006). Clearance of IL-8 increased by 0.47 ± 0.08 pg/ml for each unit increase in pre-dialysis IL-8 (p < 0.001) and decreased by 5.63 ± 2.59 pg/ml for each unit increase in pre-dialysis urea mmol/l (p < 0.05). In conclusion, the results of our study demonstrate that a hemodialysis session markedly decreases IL-8 concentration, which is significantly affected by pre-dialysis concentrations, indicating that removal of IL-8 is a concentration gradient-dependent action, but does not change the serum levels of IL-1β, sIL-2R, IL-6, and TNF-α, underlining importance of the structural characteristics of the molecules.