High fever, low GCS, and high lactate: independent risk factors for progression of influenza-associated encephalopathy to acute necrotizing encephalopathy in children

Influenza-associated encephalopathy(IAE), as the most severe neurological complication of influenza virus infection, has become an increasingly severe public health challenge in the global pediatric field. Acute necrotizing encephalopathy(ANE) is a malignant subtype of IAE and currently shows a significant upward trend. Therefore, early identification of independent risk factors for the progression of IAE to ANE is crucial. A retrospective analysis was conducted on the clinical data of children diagnosed with IAE who were hospitalized at Wuhan Children’s Hospital from January 2020 to January 2025. According to whether ANE occurred during hospitalization, the children were divided into the ANE group and Non-ANE for comparative study. SPSS was used to analyze the risk factors of ANE. Among 55 children diagnosed with IAE, 25 progressed to ANE. Compared with Non-ANE group, the risk factors for progression to ANE were peak fever, GCS score, and lactate. The areas under the curve (AUC) for distinguishing IAE and ANE using peak fever, GCS score, and lactate were 0.751, 0.675, and 0.765, respectively. The sensitivity and specificity of a peak fever ≥ 39.7℃ were 60% and 83.33%, respectively; for a GCS score ≤ 5, the sensitivity was 44% and specificity 96.67%; for lactate > 2.87, the sensitivity was 60% and specificity 83.33%. When the three risk factors were combined to diagnose ANE, the AUC was 0.912, with sensitivity and specificity of 72% and 96.67%, respectively. The combination of high fever peak, low GCS score, and high lactate level can serve as early predictors of ANE; however, due to the limitations of retrospective single-center small sample data, further confirmation from multi-center large sample studies is needed in the future.