Predictive value of the neutrophil percentage-to-albumin ratio for treatment outcomes in patients with peritoneal dialysis-associated peritonitis

ObjectiveTo investigate the predictive value of the neutrophil percentage-to-albumin ratio （NPAR） for treatment outcomes in patients with peritoneal dialysis-associated peritonitis （PDAP）.MethodsClinical data of 231 PDAP patients hospitalized in the Department of Nephrology， the Second Affiliated Hospital of Anhui Medical University， from January 1， 2016 to April 30， 2025， were retrospectively analyzed. According to treatment outcomes， the patients diagnosed with PDAP were divided into a cured group and a treatment failure group. The differences in relevant laboratory indicators and NPAR at the first blood draw after admission， as well as the predictive value of NPAR for treatment outcomes in PDAP patients， were compared between the two groups.ResultsAs of April 30， 2025， a total of 231 PDAP patients who met the inclusion and exclusion criteria were enrolled in this study， including 193 episodes in the cure group （83.5%） and 38 episodes in the treatment failure group （16.5%）. Compared with the cure group， the treatment failure group had longer dialysis vintage （Z=-3.621， P<0.001）， higher blood C-reactive protein （C-reactive protein， CRP） （Z=-3.329， P<0.001）， higher white blood cell count （Z=-1.982， P=0.047）， higher neutrophil count （Z=-2.306， P=0.021）， and higher NPAR （Z=-5.542， P<0.001）， but lower body mass index （BMI） （t=2.411， P=0.019）， lower lymphocyte count （Z=3.554， P<0.001）， and lower serum creatinine （Z=2.0， P=0.046）. Univariate logistic regression analysis showed that longer dialysis vintage （OR=1.019， 95%CI： 1.009-1.029， P<0.001）， higher CRP （OR=1.006， 95%CI： 1.002-1.010， P=0.001）， and higher NPAR （OR=1.148， 95%CI： 1.091-1.208， P<0.001）， as well as lower BMI （OR=0.90， 95%CI： 0.811-0.999， P=0.049）， lower lymphocyte count （OR=0.153， 95%CI： 0.050-0.467， P<0.001）， and lower serum creatinine （OR=0.999， 95%CI： 0.997-1.000， P=0.039）， were risk factors for treatment failure in patients with PDAP. Multivariate logistic regression analysis showed that longer dialysis vintage （OR=1.018， 95%CI： 1.006-1.029， P=0.002） and higher NPAR （OR=1.099， 95%CI： 1.036-1.167， P=0.002） were independent risk factors for treatment failure in patients with PDAP. In this center， the maximum area under the receiver operating characteristic （ROC） curve （AUC） for NPAR in predicting PDAP treatment failure was 0.785 （95%CI： 0.710-0.859）， with a sensitivity of 73.7%， a specificity of 74.6%， and an optimal cutoff value of 31.27. The maximum AUC for dialysis vintage in predicting PDAP treatment failure was 0.686 （95%CI： 0.593-0.779）， with a sensitivity of 44.7%， a specificity of 83.4%， and an optimal cutoff value of 68.50. The combined prediction of the two yielded a maximum AUC of 0.816 （95%CI： 0.748-0.885）， with a sensitivity of 76.3%， a specificity of 73.1%， and an optimal cutoff value of 0.14.ConclusionLonger dialysis vintage and higher NPAR are independent risk factors for treatment failure in patients with PDAP， and their combined use provides a higher predictive value for treatment failure.