Sex: M
Vaccine: COVID19
Symptoms: Blood glucose, Blood test, CSF immunoglobulin G index, CSF protein, CSF test
Clinical narrative: Anti-LGI1 encephalitis after mRNA COVID-19 vaccination; This is a literature report for the following literature source(s).  A 56-year-old male patient received BNT162b2 (BNT162B2), as dose 2, single (Batch/Lot number: unknown) for covid-19 immunisation. The patient's relevant medical history and concomitant medications were not reported. Vaccination history included: Bnt162b2 (DOSE 1, SINGLE), for COVID-19 immunisation, reaction(s): "Anti-LGI1 encephalitis after mRNA COVID-19 vaccination". The following information was reported: ENCEPHALITIS AUTOIMMUNE (hospitalization, medically significant, life threatening), outcome "recovering", described as "Anti-LGI1 encephalitis after mRNA COVID-19 vaccination". The patient underwent the following laboratory tests and procedures: Blood glucose: elevated; Blood test: Positive, notes: for LGI1 antibodies; Computerised tomogram abdomen: showed no signs of malignancy; Computerised tomogram pelvis: showed no signs of malignancy; Computerised tomogram thorax: showed no signs of malignancy; CSF immunoglobulin G index: elevated; CSF protein: elevated; CSF test: Positive, notes: for LGI1 antibodies; showed elevated, notes: glucose, protein and IgG synthesis rate; Electroencephalogram: frequent faciobrachial dystonic seizures, notes: and three left hemisphere electrographic seizures associated with chills, piloerection and emotional distress (pilomotor seizures); Heart rate: 120-130, notes: throughout the recording; Interleukin level (0-13): 38.7 pg/mL; paraneoplastic panel: Negative; Labs: were significant for hyponatremia; Magnetic resonance imaging head: demonstrated T2/fluidattenuated, notes: inversion recovery signal abnormality involving bilateral mesial temporal lobes, left temporal pole and left insulation; Mini mental status examination: 20/30; Polymerase chain reaction: Negative; SARS-CoV-2 test: Negative. Therapeutic measures were taken as a result of encephalitis autoimmune.  Clinical information: A 56-year-old man with no significant past medical history developed episodic heart palpitations and dizziness with chills 2 weeks after his first dose of the BNT162b2 mRNA COVID-19 Vaccine (Pfizer). Symptoms became more frequent after his second dose of the same vaccine (Pfizer). He presented to the neurology clinic with cognitive impairment and behavioral changes 3 months later. Clinically, he displayed impulsive episodes characterized by a sudden rise from a seated position stepping forward with preserved consciousness. His score on the Mini-Mental State Examination was 20/30. A COVID PCR test was negative. He was admitted for long-term video EEG monitoring which captured frequent faciobrachial dystonic seizures (FBDS) and three left hemisphere electrographic seizures associated with chills, piloerection and emotional distress (pilomotor seizures). His heart rate was in the range of 120130 throughout the recording. MRI brain demonstrated T2/fluid attenuated inversion recovery signal abnormality involving bilateral mesial temporal lobes, left temporal pole and left insula. Labs were significant for hyponatremia and an elevated serum interleukin-6 of 38.7 pg/ml (013). CSF analysis showed elevated glucose, protein and IgG synthesis rate. Meningitis/encephalitis PCR panel and araneoplastic panel were negative. CT chest, abdomen and pelvis showed no signs of malignancy. No additional pilomotor seizures were recorded after Vimpat was started, but FBDS persisted. IV methylprednisolone (IVMP) 1 g was subsequently started for suspected autoimmune encephalitis based on CSF and MRI brain findings. He improved significantly after IVIMP was initiated. Ultimately, his serum and CSF came back positive for LGI1 antibodies, and he was diagnosed with anti-LGI1 encephalitis. He finished 5 days IVMP followed by IVIG 2 g/kg and discharged on steroid taper. He remained seizure free with a mild executive function deficit 1 year after symptom onset.   No follow-up attempts are possible.; Sender's Comments: Based on the available information and implied temporal association, a causal relationship between the reported event Encephalitis autoimmune and suspect product cannot be excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.