Sorbents in the treatment of renal failure

Standard renal replacement therapy in acute renal failure (ARF) and end-stage renal disease (ESRD) is based on membrane technology. The transition from natural cellulosic membranes to synthetic membranes has not been associated with improvement in mortality rates. Modifications of dialysis with continuous arteriovenous hemofiltration and hemodiafiltration to remove middle molecular weight toxins, low molecular weight proteins and peptides (LMWP) and cytokines involved in inflammation appear to have reached their limits. High flux dialyzers are not efficient at removing LMWP and for this reason sorbents to augment or replace dialysis have been used in clinical trials. Removal of LMWP such as β2-microglobulin, leptin, complement factor D, angiogenin, and cytokines such as IL-1, IL-6, IL-10, IL-18 and TNFα, have been established in animal models of sepsis, and in ESRD patients using sorbents in conjunction with high flux dialysis. Sorbent devices added to hemodialysis, or alone in inflammatory states, are being studied in diseases which possess a common pathway of systemic inflammatory response syndrome; these states are sepsis, ARF cardio-pulmonary bypass, in brain dead subjects prior to explantation of donor organs and ESRD.