Serum procalcitonin and other biologic markers to distinguish between bacterial and aseptic meningitis

Objective: To identify the biologic tests that best distinguish between bacterial and aseptic meningitis in an emergency department (ED). Study design: All children hospitalized for bacterial meningitis between 1995 and 2004 or for aseptic meningitis between 2000 and 2004 were included in a retrospective cohort study. Predictive values of blood (C-reactive protein, procalcitonin [PCT], white blood cell [WBC] count, neutrophil count) and cerebrospinal fluid (CSF) findings (protein, glucose, WBC count, neutrophil count) available in the ED were determined. Tests with the best predictive value were identified by using univariate and multivariate analyses and ROC curves comparison. Results: Among the 167 patients included, 21 had bacterial meningitis. The CSF gram-stain and bacterial antigen test had 86% and 60% sensitivity rates, respectively. PCT (>= 0.5 ng/mL) and CSF protein (>= 0.5 g/L) were the best biologic tests, with 89% and 86% sensitivity rates, 89% and 78% specificity rates, adjusted odds ratios of 108 (95% CI, 15-772) and 34 (95% Cl, 5-217), and areas under the ROC curves of 0.95 and 0.93, respectively. Conclusion: PCT and CSF protein had the best predictive value to distinguish between bacterial and aseptic meningitis in children.