AMPAR encephalitis in a child with short-term amnesia after COVID-19 vaccination – A case report

We report a 12-year-old boy that developed α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR) encephalitis, a rare condition in children, 15 days after receiving the Pfizer-BioNTech COVID-19 vaccine. Initially presenting with short-term amnesia, he showed normal results on EEG and brain MRI. Antibodies against AMPAR were found in his cerebrospinal fluid (CSF). Cancer screenings were normal. The patient was treated with intravenous human immunoglobulin (IVIG) for five days, but relapsed 45 days later. Upon relapse, he received IVIG, dexamethasone, and rituximab, leading to full recovery. While a temporal connection suggests a potential link between vaccination and encephalitis, this has not been previously documented and could be coincidental. Further studies are needed to confirm any causation. Early suspicion and treatment of this condition are crucial for a better prognosis. • A child was diagnosed with AMPAR encephalitis after receiving a COVID-19 vaccine • This is a rare disorder in children, and has not previously been linked to vaccination • Aggressive therapy with IVIG, dexamethasone and rituximab resulted in a good outcome