New onset limbic encephalitis and COVID-19 vaccine: a case report

ABSTRACT

Background: Autoimmune limbic encephalitis (ALE) is an inflammatory disease involving the medial temporal lobes. It is characterized by subacute onset of short-term memory deficits, seizures and psychiatric disorders. Few new cases of ALE associated both with SARS-CoV2 infection and COVID-19 vaccine have recently been described. Case presentation A 56-year-old woman was admitted to emergency department for persistent fever and acute onset of confusion few days apart the first dose of BNT162b2 COVID-19 vaccine. Neurological examination revealed confusion and short-term memory loss. Blood test showed only leukopenia and mild increase of the PCR. The patient underwent brain CT-scan which excluded organic lesion for the cognitive deficit. During the hospitalization the patient presented tonic clonic seizures and postictal state therefore an EEG was performed and revealed epileptiform abnormalities in the temporal lobes. Since the hypothesis of encephalitis brain MRI and lombar puncture for cerebral spinal fluid (CSF) analysis were performed with evidence of T2 hyperintensity in temporal lobes and normal values of CSF. Despite steroid and antiepileptic therapy with Carbamazepine, Valproate and Perampanel, several epileptic relapses occurred and there was no improvement of neurological manifestation. The patient was finally discharged with need of home care Conclusions: New onset ALE following COVID-19 vaccine or infection has rarely been described. Clinicians should monitor neurological symptoms to ensure appropriate therapy to maximize the likelihood of good outcome.