Comparison of Acute COVID-19 Encephalopathy with Seasonal Influenza A-associated Encephalopathy

Objectives: To compare the clinical presentations and neurobiological features in children with acute Coronavirus disease 2019 (COVID-19) encephalopathy and Seasonal influenza A virus (IAV)-associated encephalopathy. Methods: We conducted a retrospective cohort study on patients diagnosed with COVID-19 encephalopathy between December 15, 2022, and January 15, 2023, and children diagnosed with IAV-associated encephalopathy between November 2017 and March 2023, who were less than 18 years old at the Children’s Hospital, Zhejiang University School of Medicine. Results: A total of 34 patients with acute COVID-19 encephalopathy and 37 patients with IAV-associated encephalopathy were included in this study. Elevation of cerebrospinal fluid (CSF) pleocytosis and CSF glucose, as well as downregulation of monocyte and TNF-α, were observed in both the COVID-19 ICU group and the moderate & severe group. The median age was younger (P < 0.001) and the median time for the occurrence of neurological symptoms was shorter (P < 0.001) in the COVID-19 group compared with the IAV group. More patients in the IAV group had altered levels of consciousness (P < 0.001) and were admitted to the ICU (P < 0.001). Consequently, more severe cases were observed in the IAV group (P = 0.007). Brain imaging showed a predominance appearance of acute necrotizing encephalopathy in the IAV group (P = 0.038). Regarding blood parameters, leukomonocyte levels were lower in the IAV group (P = 0.003) with lower expression of CD4 (P = 0.047). Random blood glucose (P = 0.001), D dimer (P = 0.004), and cytokine IL-2 (P = 0.005) were lower in the COVID-19 group, while IFN-γ (P = 0.013) was significantly higher. Conclusions: Influenza A virus-associated encephalopathy presented more severe manifestations. However, IFN-γ may act as a protective cytokine in COVID-19 encephalopathy.