Fig. 4

Neopterin, kynurenine metabolites, and ratios in patients with encephalitis (Enc, n = 10), viral meningitis (VM, n = 12), and bacterial meningitis (ABM, n = 6) in comparison with controls (Ctr, n = 22). Data shown are median with IQR, and all were significant in the analysis of variance with the Kruskal-Wallis test. Comparisons of two groups were analyzed by Mann-Whitney U test. Asterisks above patient groups indicate significant difference vs controls, asterisks above horizontal lines indicate significant differences between individual groups (Mann-Whitney U test): *p < 0.05, **p < 0.01, and ***p < 0.001. a: TRP levels below the lower level of detection (LOD) for 9 patients with CNS infection were adjusted to this value (0.4 μM) for calculation of the KYN/TRP ratio as the expression of IDO activity (KYN (nmol)/TRP(μmol))