Influence of SARS-CoV-2 omicron variant infection on seizure occurrence among children: The large-scale multicenter study

Purpose: During the pandemic of the coronavirus disease 2019 (COVID-19) Omicron variant, we experienced an increase in patients with COVID-19-associated seizures. However, there was a lack of literature about the occurrence of seizures according to different pandemics. Therefore, we investigated the characteristics of seizures in pediatric patients before and after the spread of the Omicron variant. Method: We analyzed the clinical findings of pediatric patients who visited outpatient clinics or emergency rooms and were diagnosed with COVID-19 at seven hospitals in Korea from 2020 to 2022. We divided the participants into pre-Omicron and post-Omicron groups based on whether it was before or after January 1, 2022, the onset of the Omicron variant pandemic in Korea. We then compared seizure incidence and clinical characteristics between the two groups. Result: We enrolled 1608 patients aged 5.2 +/- 4.8 years. Among post-Omicron group (n = 1293), 286 (22 %) patients presented with COVID-19-associated seizures; in contrast, only one (0.3 %) patient in pre-Omicron group (n = 315). Status epilepticus occurred in 18 (6.2 %) patients, multiple seizures in 64 (22 %), and afebrile seizures in 33 (11.5 %). Clinical diagnoses of seizures were seizures associated with COVID-19 infection (239/286, 83.6 %), epilepsy (39/286, 13.6 %), neuroinflammatory disease (4/286, 1.4 %), seizures associated with multisystem inflammatory syndrome in children (MIS-C, 4/286, 1.4 %), and hyponatremic seizures (1/286, 0.3 %). Conclusion: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant is associated with a high incidence of seizure as a presenting symptom. Clinical diagnoses vary, including seizures associated with the SARS-CoV-2 omicron variant without a definitive diagnosis, epilepsy, MIS-C, neuroinflammatory disease, and hyponatremia.