Immune-mediated encephalitis following SARS-CoV-2 vaccinations

Abstract

Objectives: one of the neurological side effects of SARS-CoV-2 vaccinations is immune encephalitis. This review aims at summarising previous and current findings on the frequency, clinical presentation, diagnosis, treatment, and outcome of SARS-CoV-2 vaccination-associated encephalitis (SC2VIE).

Methods: narrative review of eligible articles meeting defined search criteria and published between January 2021 and January 2024.

Results: A total of 21 patients with SC2VIE reported in 18 articles were included. The AstraZeneca vaccine (ChAdOx1) was the trigger in 10 cases, the Biontech Pfizer vaccine (BNT162b2) in 8 cases, and the Moderna (mRNA1273), CoronaVac, and Sinopharm vaccine (BBIBP-CorV) in one case each. The ages ranged from 21 to 82 years. Twelve patients were female. SC2VIE developed after the first dose in eight patients, after the second in six patients, and in two after the third dose. The latency between vaccination and onset of clinical manifestations ranged from 1 to 56d. Eighteen patients received steroids, one patient intravenous immunoglobulins, one patient plasmapheresis, and two patients rituximab. Complete recovery was achieved in nine patients and incomplete recovery in ten.

Conclusions: SC2VIE is not an uncommon complication of SARS-CoV-2 vaccinations. The clinical presentation and treatment of SC2VIE do not differ from those of autoimmune encephalitis of other causes. Since SC2VIE can manifest only as a psychiatric disease, patients with post-SARS-CoV-2 vaccination psychosis should be evaluated for SC2VIA. The outcome of SC2VIE depends largely on the severity of the immune response and comorbidities.

Keywords: COVID-19; Encephalitis; SARS-CoV-2; Side effect; Vaccination.