In terms of defining potential biomarkers, previous studies identified CXCL8 and tumour necrosis factor-α as potentially useful in determining whether patients have bacterial CNS infection (Mukai et al., 2006; Hsieh et al., 2009; Pinto Junior et al., 2011; García-Hernández et al., 2016; Srinivasan et al., 2016, 2018), although none of these were sufficiently predictive for differentiating infection from inflammation. Here, CXCL8 is linked to infection.