Median CRP concentration in CSF in the whole cohort was 0.00 (IQR 0.00–0.00), with 3.02 (IQR 1.40–8.42) in bacterial meningitis patients, and 0.00 (IQR 0.00–0.00) in all other patients (Fig. 1, Supplementary Fig. S2 and Table S2). This evidence concerns the gene CRP and bacterial meningitis.