Post-COVID-19 Vaccination Meningitis and Meningoencephalitis: A Systematic Review of Case Series and Case Reports.

Meningitis and meningoencephalitis, as inflammatory diseases of the brain parenchyma, are serious events reported sporadically after coronavirus disease 2019 (COVID-19) vaccination. However, there is a lack of systematic reviews consolidating these reported cases. By using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted across PubMed, Scopus, Embase, and Web of Science databases. All case reports and series discussing the emergence of meningitis and meningoencephalitis after COVID-19 vaccination were included and evaluated using the Joanna Briggs Institute critical appraisal tool. Out of 967 records, 27 studies with 31 patients were eventually included. The most commonly reported symptoms were headaches and fever. About one-third of the patients exhibited positive meningeal signs. Most of the findings in the computed tomography scans and magnetic resonance images revealed no significant changes or enhancement in the leptomeninges. Cerebrospinal fluid analysis dominantly suggested aseptic meningitis, and about 80.6% of the patients experienced a full recovery. After a detailed review of the reported cases, further research is needed to establish a definitive correlation between meningitis and COVID-19 vaccination on a larger scale.