Advances in peritoneal dialysis: a review

Peritoneal dialysis (PD) is a simple, "low-tech" form of renal replacement therapy that is less expensive than conventional in-center hemodialysis in many parts of the world. Despite the advantages associated with this modality, it has not been as embraced as it deserves to be in many countries, including the United States. This brief review will focus on recent interesting and germane publications related to therapy with PD, centering on three broad themes: (i) "biocompatible" PD solutions; (ii) encapsulating peritoneal sclerosis; and (iii) comparisons of survival between PD and conventional hemodialysis. Recent publications concerning biocompatible solutions are hampered by varying trial designs, confounding by indication, and solutions with different compositions. Perhaps the most robust result, a reduction in peritonitis, has not been a consistent finding across studies. The results are generally disappointing with respect to clinically relevant endpoints such as membrane function and patient survival. The rarity of encapsulating peritoneal sclerosis, still a vexing and worrying complication, hampers any systematic examination of pathogenesis and treatment. The establishment of registries may help to better understand this condition. In the absence of randomized, controlled trials of PD versus hemodialysis, survival analyses are fraught with enormous methodological and statistical pitfalls. Nevertheless, many investigators remain focused on small differences in survival between the two modalities; even more inappropriately, some clinicians use these imperfect data to guide their modality recommendations. Recent outcome studies suggest that the survival of patients on PD compared with conventional hemodialysis is astonishingly similar, and differences between early and late survival are more explainable by the circumstances around initiation than by the modality itself.