The new peritoneal dialysis solutions: friends only, or foes in part?

Over the past decade new solutions for peritoneal dialysis have been developed in an effort to reduce the bioincompatibility of conventional glucose-containing, lactate-buffered solutions, and thereby to improve the clinical outcomes of peritoneal dialysis. The new solutions contain either other non-glucose osmotic agents, such as glucose polymers or amino acids, or have a neutral pH; the buffer content is altered in some of the new solutions. In vitro and in vivo studies have shown the biocompatibility of these new solutions to be superior to that of standard solutions. In this paper, available clinical data on the use of these new solutions are reviewed. In general, the data indicate improved biocompatibility of the new solutions; a number of studies, however, detected no superiority when levels of accepted markers of biocompatibility, such as vascular endothelial growth factor or hyaluronic acid, were measured. This finding could be explained by the assumption that the new peritoneal dialysis solutions not only induce less damage to the peritoneal membrane but also better maintain repair mechanisms, which apparently are associated with enhanced release of such markers.