Predicting Factors for Acute Encephalopathy in Febrile Seizure Children with SARS-CoV-2 Omicron Variant: a Retrospective Study

Background: SARS-CoV-2 posed a threat to children during the early phase of Omicron wave because many patients presented with febrile seizures. The study aimed to investigate predicting factors for acute encephalopathy of children infected by SARS-CoV-2 Omicron variant presenting with febrile seizures.

Methods: The retrospective study analyzed data from pediatric patients who visited the emergency department of Chang Gung Memorial Hospital in Taiwan between April and July 2022. We specifically focused on children with COVID-19 who presented with febrile seizures, collecting demographic, clinical, and laboratory data at the pediatric emergency department, as well as final discharge diagnoses. Subsequently, we conducted a comparative analysis of the clinical and laboratory characteristics between patients diagnosed with acute encephalopathy and those with other causes of febrile seizures.

Results: Overall, 10,878 children were included, of which 260 patients presented with febrile seizures. Among them, 116 individuals tested positive for SARS-CoV-2 and of them, 14 subsequently developed acute encephalopathy (12%). Those with acute encephalopathy displayed distinctive features, including older age (5.1 vs. 2.6 years old), longer fever duration preceding the first seizure (1.6 vs. 0.9 days), cluster seizure (50% vs. 16.7%), status epilepticus (50% vs. 13.7%) and occurrences of bradycardia (26.8% vs. 0%) and hypotension (14.3% vs. 0%) in the encephalopathy group. Besides, the laboratory findings in the encephalopathy group are characterized by hyperglycemia (mean (95% CI) 146 mg/dL (95% CI 109-157) vs. 108 mg/dL (95% CI 103-114) and metabolic acidosis (mean (95% CI) pH 7.29(95% CI 7.22-7.36) vs. 7.39 (95%CI 7.37-7.41)).

Conclusions: In pediatric patients with COVID-19-related febrile seizures, the occurrence of seizures beyond the first day of fever, bradycardia, clustered seizures, status epilepticus, hyperglycemia, and metabolic acidosis should raise concerns about acute encephalitis/encephalopathy. However, the highest body temperature and the severity of leukocytosis or C-reactive protein levels were not associated with poor outcomes.