Assessment of selected inflammatory markers in bacterial and viral neuroinfections in children

Aim: The aim of the study was to assess the suggested biomarkers’ usefulness in diagnosing central nervous system infections in order to optimise treatment and minimise adverse outcomes. The study included a comprehensive comparison of the known parameters and a search for correlations with proposed biomarkers. Materials and methods: The data of 73 hospitalised children were reviewed. According to their final diagnoses, 42 participants were assigned to the control group, 13 to the cohort with bacterial and 18 to the cohort with viral neuroinfections. The children underwent clinically indicated blood and cerebrospinal fluid tests. The serum interleukin (IL)-1β, IL-6 and neopterin concentrations, and S100B protein and matrix metalloproteinase (MMP)-9 levels in the cerebrospinal fluid were determined. The results were compared between the groups and correlations were sought. Results: Serum IL-6 levels were found to have increased in viral (p = 0.0412) and bacterial (p < 0.0001) infections, with a predominance of the latter (p = 0.0403). In terms of serum neopterin and IL-1β, the neuroinfection cohort did not differ from the control group. The level of S100B in the cerebrospinal fluid in bacterial disease was higher compared with the viral aetiology (p = 0.0325). The cerebrospinal fluid S100B correlated positively with serum IL-6 (p = 0.0138, R = 0.6396) and reversely with IgA and IgG levels (p = 0.0499, R = −0.5325; p = 0.0022, R = −0.7451, respectively) in the neuroinfection cohort. The cerebrospinal fluid MMP-9 was linked with cerebrospinal fluid cytosis in patients with viral (p = 0.0018, R = 0.7547) and bacterial (p = 0.0124, R = 0.6935) disease. The serum IL-6 levels correlated with IgA in the viral aetiology (p = 0.0374, R = 0.9). Conclusions: The MMP-9 level correlated with blood–brain barrier permeability, expressed by cerebrospinal fluid proteins and cytosis, which may indicate the possibility of sequelae. The higher serum concentrations of IL-6 and S100B in bacterial neuroinfections may reflect a more intense immune reaction associated with this aetiology.