High serum DcR3 levels are associated with the occurrence of peritonitis in patients receiving chronic peritoneal dialysis

Background: Peritoneal dialysis (PD)-related peritonitis is a serious complication that typically leads to hospitalization, catheter loss, and even mortality. Previous studies of the risk factors for peritonitis are discordant. To date, no biomarker associated with PD-related peritonitis has been investigated. However, it has been shown that serum decoy receptor 3 (DcR3) is a valuable marker in predicting the outcome of several inflammatory diseases. The aim of this study was to investigate whether serum DcR3 is a predictor of peritonitis in chronic PD patients. Methods: We conducted a prospective cohort study of PD patients in the PD unit of a tertiary referral center from March 1 to November 30, 2007, and followed up until December 31, 2009. Clinical and laboratory parameters were recorded and serum DcR3 was measured to assess risk factors for developing PD-related peritonitis. Results: A total of 77 patients (38 men and 39 women; mean age 58 ± 13 years) were enrolled in this study. The average time on PD was 24.5 months and 46 patients (60%) were diabetic. The mean follow-up duration was 499 ± 17 days. The rate of peritonitis incidence was 0.17 episodes per patient-year. Baseline serum DcR3 in 77 patients was 1.94 ± 1.23 ng/mL. Kaplan–Meier survival analysis showed that patients with serum DcR3 > 1.8 ng/mL had a higher risk of peritonitis than those with serum DcR3 < 1.8 ng/mL (p = 0.016). The Cox proportional hazard model further showed that high serum DcR3 (>1.8 ng/mL) was an independent risk factor for subsequent peritonitis (hazard ratio 3.61, 95% CI 1.17–11.08; p = 0.03). Conclusion: Serum DcR3 was associated with increased risk of PD-related peritonitis