Anti-NMDA receptor encephalitis following SARS-CoV-2 infection in children

The purpose of this study was to report the phenomenon of anti-N-methyl-d-aspartate (anti-NMDA) receptor encephalitis following novel coronavirus disease 2019 (COVID-19), to minimize misdiagnoses of this as post-COVID-19 syndrome, and to promote early identification, enabling these patients to benefit from early immunotherapy.

The study included three pediatric patients with anti-NMDA receptor encephalitis following COVID-19, treated at our hospital from July to September 2023. We collected and analyzed the clinical data from these patients, including background information, clinical presentations, laboratory examination results, imaging results, electrophysiological results, treatment, and prognosis.

Three patients presented with varying degrees of nonspecific symptoms, including recurrent dizziness, headache, and/or sleep disturbance, after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, initially considered as post-COVID-19 syndrome. After 2 months, 3 months, and 5 months, they developed seizures, speech disturbance, motor abnormalities, mood abnormalities, and other neuropsychiatric symptoms, with elevated cerebrospinal fluid monocytes, positive cerebrospinal fluid SARS-CoV-2-IgG, and anti-NMDAR-IgG. They were diagnosed with anti-NMDA receptor encephalitis following novel coronavirus disease. They were treated with intravenous immunoglobulin and corticosteroids, and each made a general recovery.

SARS-CoV-2 virus infection may be a trigger for the development of anti-NMDAR encephalitis. When neurological symptoms (even some nonspecific symptoms) are present following SARS-CoV-2 virus infection, neuroantibody assays are warranted to enable such patients to reap the potential benefits of early immunotherapy treatment.