CRP and bacterial meningitis: Median CRP concentration in CSF in the overall cohort was 0.00 (IQR 0.00–0.58), with 1.63 mg/L (IQR 0.49–5.36) in bacterial meningitis, and 0.00 mg/L (IQR 0.00–0.00) in viral CNS infections (Fig. 1, Supplementary Fig. S2 and Table S2).