In this study, S–PCT had a 95% sensitivity, 100% specificity, and 100% negative predictive value, as well as a 97% positive predictive value for distinguishing BM versus Viral Meningitis (VM) when using a diagnostic cut-off level of 0.28 ng/mL (AUC, 0.99; 95% CI, 0.99 to 1) [17]. Here, CALCA is linked to viral meningitis.