Peritoneal dialysis solution biocompatibility: definitions and evaluation strategies.

It is well established that materials employed for medical diagnostic and therapeutic purposes require biocompatibility testing before human use, as evidenced by the comprehensive and general guide to biocompatibility testing published in the International Standard ISO-10993 [1]. Similarly, in hemodialysis, biocompatibility profiling has become a prerequisite for any new membrane that is developed [2‐5]. This requirement has been in response to the recognition that biocompatibility may play an important role both in acute intradialytic symptoms and chronic morbidities associated with hemodialysis therapy, such as susceptibility to infection, osteodystrophy, and amyloidosis. Today, biocompatibility profiling of peritoneal dialysis (PD) solutions has become an important feature of both conventional and new dialysis solution performance [6‐11]. It is now over 20 years since the in vitro detrimental effects of commercial dialysis solution on phagocyte function were first described [12]. Since this time, there has been a plethora of reports describing a wide variety of approaches, techniques, and results of biocompatibility PD solution testing. The impetus for this proliferation of research is the growing belief that the first generation of commercially available PD solutions that have low pH, high lactate and glucose concentrations, are hyperosmolar, and contain glucose degradation products that may be causally associated with some of the complications of PD therapy [7, 8, 13‐19]. Examples of the latter are pain upon infusion in the acute setting and loss of ultrafiltration in the long-term patient. The aim of this review is to discuss definitions of biocompatibility, the hierarchical testing schemes that are often selected for biocompatibility testing, how these schemes relate to contemporary models of structural and functional alterations of the peritoneal membrane, and the associated clinical consequences. Finally, an example of how the results of such a biocompatibility testing scheme helped to