The association between exit site infection and subsequent peritonitis among peritoneal dialysis patients.

BACKGROUND AND OBJECTIVES: Peritonitis is the most common infectious complication seen in peritoneal dialysis (PD). Traditionally, exit site infection (ESI) has been thought to predispose PD patients to peritonitis, although the risks have not been quantified. This study aimed to quantify the risk of PD peritonitis after ESI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Data from 203 clinically stable PD patients >18 years of age who were followed as part of a randomized controlled trial over 18 months were used to estimate the risk of developing peritonitis within 30 days of an ESI compared with individuals who did not have a recent ESI. Sensitivity analyses were performed at 15, 45, and 60 days.

RESULTS: Patients were mostly male (64.5%) and Caucasian, with a mean age of 60.5 ± 14.4 years. There were 44 ESIs and 87 peritonitis episodes during the 18-month study. Seven patients had an ESI followed by peritonitis within 30 days. Using a frailty model, patients who had an ESI had a significantly higher risk of developing peritonitis within 30 days, even if the ESI was appropriately treated. This risk was maximal early on and diminished with time, with hazard ratios (95% confidence interval) of 11.1 at 15 days (HR=11.1, 95% CI=4.9-25.1), 5.3 at 45 days (2.5-11.3), and 4.9 at 60 days (2.4-9.9). In 2.3% of patients, subsequent peritonitis was caused by the same organism as the previous ESI.

CONCLUSIONS: A strong association between a treated ESI and subsequent PD peritonitis was present up to 60 days after initial diagnosis.