IL6 and infection: Serum IL-6 levels were unchanged in patients with meningitis as compared to aSAH patients without infections (Figure 4C) except on day 3 as shown by multivariate analysis revealing a negative independent association between serum IL-6 and meningitis (OR = 0.002, p = 0.024, 95% CI = 0.0–0.4) (see also Table S1).