Biocompatibility of the new peritoneal dialysis solutions. Basic features

Abstract

Over time, peritoneal dialysis (PD) produces morphological and functional changes in the peritoneal membrane. This process is related to uremic status as well as to continuous exposure to PD solutions. Novel PD fluids (PDFs) have greater biocompatibility, as they are designed to minimize the formation of glucose degradation products (GDPs) and the ready-to-use solution has a neutral pH. These properties have been achieved in both the balance and the bicavera ® solutions manufactured by Fresenius Medical Care (Bad Homburg, Germany). GDPs are strong catalysts of the formation of advanced glycation end products (AGE). In turn, AGEs, mediated by interaction with their receptor RAGE, lead to various cellular responses, such as up-regulation of inflammatory markers and cellular transdifferentiation. Moreover, cell growth, viability and functionality are impaired in the presence of GDPs, but are less affected if low GDP solutions are applied. Structural changes in the peritoneal membrane, such as membrane thickening and neovascularization are less pronounced with low GDP solutions than with conventional solutions. A more intact structure of the peritoneal membrane is further suggested by the increased levels of CA125, a marker of mesothelial cell mass and function associated with the use of biocompatible PDFs. As a consequence of these alterations, functional changes in the peritoneal membrane are also associated with AGE deposits, correlating with increased membrane permeability and decreased ultrafiltration capacity. Evidence supports further a systemic effect of GDPs present in PDF on serum AGE. Low GDP solutions exert both fewer local effects on the peritoneal membrane and less pronounced systemic effects. Clinical studies show better preservation of residual renal function and improved survival with the use of low GDP solutions.