Predictors of culture-negative peritoneal dialysis-associated peritonitis: a single center, retrospective study

Abstract

Background: Empirical antibiotic treatment against peritoneal dialysis (PD)-related peritonitis should be immediately initiated before PD effluent culture results are obtained. As culture results guide the choice of antibiotics, culture-negative peritonitis (CNP) is a serious issue. In addition, the identification of the causative organism often indicates a possible source of infection. This study aimed to clarify the predictors of CNP. Methods: This single-center, retrospective study was conducted from November 2007–December 2018 in patients undergoing PD with peritonitis at our institution, where 204 peritonitis episodes (57 culture-negative, 147 culture-positive) were investigated based on demographics, and clinical parameters. CNP predictors were investigated using logistic regression. Results: CNP rate was significantly higher in female and in patients with higher platelet counts, lower dialysate cell counts at peritonitis diagnosis, and higher serum β2-microglobulin levels. In multivariate logistic regression, female sex (odds ratio [OR] 2.69, 95% confidence interval [CI] 1.31–5.54), dialysate cell count at diagnosis (OR0.99, 95% CI 0.99–0.99), and serum β2-microglobulin level (OR 1.04, 95% CI 1.00–1.07) were significantly associated with CNP. The areas under the receiver operating characteristic curve for female patients, dialysate cell counts at diagnosis of peritonitis, serum β2-microglobulin level, and female patients + dialysate cell counts at diagnosis of peritonitis + serum β2-microglobulin level were 0.604, 0.694, 0.603, and 0.751, respectively. Conclusions: Female sex, dialysate cell counts at peritonitis diagnosis, and serum β2-microglobulin levels may be predictors of CNP.