Prognostic Factors Among Children With Acute Encephalitis/Encephalopathy Associated With Viral and Other Pathogens

BACKGROUND: Acute encephalitis/encephalopathy (AE) associated with viral and other pathogens leads to neurological sequelae and mortality. Knowing the prognostic factors is therefore important for immediate interventions. We examined early-phase unfavorable prognostic factors among children with AE using a nationwide database. METHODS: We performed a retrospective cohort study using the Diagnosis Procedure Combination database, which includes approximately half of acute-care inpatients across Japan. We enrolled children aged ≤ 18 years who were hospitalized for AE and discharged from April 2010 to March 2018. The composite unfavorable outcome included the following at discharge: in-hospital death, tracheostomy, enteral tube feeding, and physical rehabilitation. Unfavorable prognostic factors were assessed using a multivariable Poisson regression model including patient characteristics, associated pathogens, and interventions within 2 days of admission adjusting for within-hospital clustering. RESULTS: This study included 9386 children with AE (median age, 3 years). A total of 241 (2.6%) in-hospital deaths occurred, and 2027 (21.6%) patients had the composite unfavorable outcome. Significant unfavorable prognostic factors were age 12-18 years, congenital anomalies, epilepsy, and Japan Coma Scale score of 100-300 at admission (ie, worse levels of consciousness). In contrast, herpes simplex virus infection and influenza virus infection were associated with favorable outcomes. CONCLUSIONS: We identified early-phase (within 2 days of admission) unfavorable prognostic factors among children with AE. These findings will help identify patients who may benefit from early aggressive therapeutic interventions.