Abstract: Objective To analyze the correlation between serum endothelial cell-specific molecule-1 (Endocan), soluble interleukin-2 receptor (sIL-2R) and inflammatory markers,and their predictive value for clinical outcomes in patients with peritoneal dialysis-associated peritonitis (PDAP). Methods A total of 121 patients with PDAP (PDAP group) and 121 patients with normal peritoneal dialysis (control group) admitted to Linyi Central Hospital from February 2019 to January 2022 were selected. The serum Endocan, sIL-2R and inflammatory markers were compared between the two groups, and the correlations were analyzed by Pearson method. The PDAP patients were divided into the cure and treatment failure groups based on clinical outcomes. Baseline data were collected, and factors influencing treatment failure in PDAP patients were analyzed using multivariate Logistic regression model. The predictive value of serum Endocan and sIL-2R in treatment failure group were analyzed using receiver operating characteristic (ROC) curves. Results The levels of serum Endocan, sIL-2R, interleukin (IL)-1β, IL-6 and hs-CRP in the PDAP group were higher than those in the control group (P<0.05). Pearson correlation analysis showed that serum Endocan, sIL-2R were positively correlated with IL-1β, IL-6 and hs-CRP in the PDAP group (P<0.05). Of 121 patients, 82 (67.77%) were cured, and 39 (32.23%) were failed treatment. The dialysis age, time from symptom onset to treatment, white blood cell (WBC) count, IL-1β, IL-6, hs-CRP, endocan and sIL-2R in the treatment failure group were higher than those in the cure group, while the serum albumin, potassium and dialysate white blood cells were lower (P<0.05). Multivariate logistic regression analysis showed that long duration from symptom onset to treatment, elevated serum endocan and sIL-2R levels were independent risk factors for treatment failure in PADP patients, and elevated serum albumin was an independent protective factor (P<0.05). ROC curve analysis showed that the area under the curve (AUC) of serum IL-1β, IL-6, hs-CRP, endocan and sIL-2R in predicting treatment failure in PDAP patients were 0.694 (95% CI, 0.604-0.775), 0.654 (95% CI, 0.562-0.738) and 0.685 (95% CI, 0.5955-0.767), 0.779 (95% CI, 0.694~0.849) and 0.720 (95% CI, 0.631~0.797), respectively. The predictive efficacy of serum endocan and sIL-2R was higher than that of IL-1β, IL-6 and hs-CRP. The combinations of serum endocan and sIL-2R (LogP mode) predicted an AUC of 0.849 (95% CI, 0.773~0.908) for treatment failure in PDAP patients. Conclusion Elevated serum endocan and sIL-2R levels were higher risk factors for treatment failure, and combinations of the two tests can predict the clinical outcomes for PADP patients.

Key words: Peritoneal dialysis-associated peritonitis, Endothelial cell-specific molecule-1, Soluble interleukin-2 receptor, Inflammatory, Clinical outcomes