No structural cerebral differences between children with a history of bacterial meningitis and healthy siblings

Aim: After bacterial meningitis, about one-third of children develops academic and/or behavioural limitations. The aim of our study was to search for structural differences in the brain, with a special focus on the hippocampus, between childhood survivors of bacterial meningitis with and without academic and/or behavioural limitations and healthy siblings. Patients and methods: A selection of a cohort, compiled in an earlier performed retrospective study, was used in this case-control study. Magnetic Resonance Imaging scans of the brain were performed in 43 post-meningitis children, of whom 18 had learning and/or behavioural limitations and 25 had no problems, and 18 controls. Voxel-based morphometry investigated the brain for structural changes. Hippocampal volume and lateral ventricle width were measured. Results: No structural differences between the groups, in any area of the brain, were found. There were no significant differences in hippocampal volume or lateral ventricle width. The group with limitations had three children with a right hippocampal volume smaller than two standard deviations below the mean of the control group. Conclusion: Despite hippocampus lesions found in experimental studies, we found no anatomical differences of the brain or hippocampus related to bacterial meningitis in children, nor to the academic and/or behavioural limitations seen after bacterial meningitis.