Peritoneal protein leakage, systemic inflammation, and peritonitis risk in patients on peritoneal dialysis.

Background: Whether peritoneal protein leakage predicts risk for peritonitis in patients on peritoneal dialysis (PD) is unknown. In this observational cohort study, we aimed to determine that association and, further, to explore if it might be explained by systemic inflammation. ♢

Methods: We prospectively followed 305 incident PD patients to first-episode peritonitis, censoring, or the end of the study. Demographics, comorbidity score, biochemistry, and peritoneal protein clearance (PrC) were collected at baseline. The predictors of first-episode peritonitis were analyzed prospectively. ♢

Results: During follow-up, 14 868 patient months and 251 episodes of peritonitis were observed. The baseline PrC was 73.2 mL/day (range: 53.2 - 102 mL/day). Patients with a high PrC were prone to be older and malnourished. They also had a higher comorbidity score and higher C-reactive protein values. In 132 first episodes of peritonitis, baseline PrC was shown to be a significant independent predictor after adjustment for age, sex, body mass index, diabetes, residual renal function, hemoglobin, and peritoneal transport rate. Systemic inflammatory markers such as serum albumin, C-reactive protein, and interleukin-6 could not explain the association of PrC and high risk for peritonitis. ♢

Conclusions: Baseline peritoneal protein leakage was able to independently predict risk for peritonitis, which is not explained by systemic inflammation. The underlying mechanisms should be explored in future.