For the roughly one in three kidney transplant candidates who arrive with a history of peritoneal dialysis complications, the stakes at the transplant table may be meaningfully higher than previously quantified. This large registry analysis reframes peritonitis not merely as a dialysis-era complication but as a durable signal of post-transplant vulnerability — information that could reshape pre-transplant risk stratification and watchful follow-up protocols.

Drawing on nearly two decades of data from the Australia and New Zealand Dialysis and Transplant Registry, investigators followed 4,957 patients who transitioned from peritoneal dialysis to kidney transplantation between 2006 and 2024. Approximately 30% had a documented history of peritonitis prior to transplant. After adjusting for confounders including obesity, comorbidity burden, smoking history, dialysis duration, and modality type, peritonitis history was independently associated with a 55% higher hazard of death-censored graft failure (aHR 1.55). The analysis also examined biopsy-proven acute rejection and all-cause mortality as secondary endpoints, with median follow-up of six years providing meaningful long-term signal.

The biological plausibility here is not trivial. Recurrent peritoneal inflammation is known to accelerate mesothelial damage and systemic immune activation, potentially priming aberrant alloimmune responses after transplantation. Earlier smaller studies hinted at this relationship, but the current cohort's size gives the hazard estimate considerably more statistical credibility. A critical limitation is the retrospective, observational design: causal inference is constrained, and unmeasured confounders — such as peritonitis episode frequency, causative organisms, or antibiotic treatment adequacy — could modulate the true relationship. The finding is also drawn from a predominantly white, high-income-country registry, limiting generalizability to more ethnically diverse or resource-limited populations. Nevertheless, this appears more than incremental: if validated prospectively, a peritonitis history could become a formal pre-transplant risk variable warranting enhanced post-transplant immunological surveillance.