Uremic toxins and peritoneal dialysis

Uremic toxicity is related in part to the accumulation of toxic substances, the nature of which has only partly been characterized. Because of the use of a highly permeable membrane and better preservation of the residual ren al function, it could be anticipated that some of these uremic toxins are m ore efficiently cleared across the peritoneal membrane, and that the plasma and tissue levels of these compounds are lower than in hemodialysis patien ts. This article analyzes the generation and removal of several uremic toxi ns in peritoneal dialysis patients. The following uremic toxins are discuss ed: beta (2)-microglobulin, advanced glycation end products, advanced oxida tion protein products, granulocyte inhibitory proteins, p-Cresol, and hyper homocysteinemia. Some recent studies are reviewed suggesting that uremic to xins are involved in the progression of renal failure and are at least part ially removed by peritoneal dialysis. We conclude that, although the plasma levels of some of these compounds are lower in peritoneal dialysis versus hemodialysis patients, it does not mean that the peritoneal dialysis patien t is "better" protected against the numerous disturbances caused by these t oxins.