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National study on pediatric acute encephalopathy in Japan (April 2020 to October 2023): Insights from the third study
Taku Omata1, Hiroshi Sakuma2, Hiroaki Nagase3
1Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
Insights
This study tracked pediatric acute encephalopathy in Japan during COVID-19, noting increased rates of hemorrhagic shock and encephalopathy syndrome (HSES) and acute fulminant cerebral edema (AFCE). Current treatments include steroid pulse therapy and mitochondrial cocktails.
Area of Science:
- Pediatric Neurology
- Infectious Diseases
- Epidemiology
Background:
- Previous national studies on acute encephalopathy in Japan were conducted between 2007-2010 and 2014-2017.
- This third study (April 2020-October 2023) occurred during the COVID-19 pandemic, allowing for comparison of trends in pediatric viral infections and treatments.
Purpose of the Study:
- To assess trends in pediatric viral infections and therapeutic practices for acute encephalopathy in Japan.
- To compare findings with previous national studies, particularly in the context of the COVID-19 outbreak.
Main Methods:
- A nationwide survey was conducted using questionnaires sent to 430 hospitals, with 241 responses.
- A secondary survey identified 622 eligible pediatric patients for data collection on background, syndrome classification, causative virus, treatment, and prognosis.
Main Results:
- The highest incidence of acute encephalopathy was observed in 1-year-olds, with peaks during COVID-19 and influenza outbreaks.
- The combined rate of Hemorrhagic Shock and Encephalopathy Syndrome (HSES) and Acute Fulminant Cerebral Edema (AFCE) increased significantly from 1.9% to 9.1%, potentially due to enhanced diagnosis and COVID-19.
- Common causative pathogens included exanthem subitum (16.1%), SARS-CoV-2 (15.9%), and influenza (7.7%). Treatment modalities included steroid pulse therapy (68.9%) and mitochondrial cocktails (42.5%).
Conclusions:
- This study offers a comprehensive overview of pediatric acute encephalopathy during the COVID-19 pandemic in Japan.
- A notable increase in HSES/AFCE incidence was observed, highlighting the impact of the pandemic and diagnostic improvements.
- Current treatment practices, including steroid pulse therapy and mitochondrial cocktails, are presented.
Background:
Previous national studies of acute encephalopathy in Japan were conducted in 2007-2010 and 2014-2017. In this third study (April 1, 2020-October 31, 2023), spanning the coronavirus disease 2019 (COVID-19) outbreak, we compared results to assess trends in pediatric viral infections and therapeutic practices.
Methods:
Questionnaires were sent to 430 hospitals of the Japanese Pediatric Society, yielding 241 responses and 1197 cases. A secondary survey to 151 facilities received 110 responses (72.8 %), identifying 622 eligible patients (604 for treatment, 544 for outcome analysis). Data on patient background, syndrome classification, causative virus, treatment, and prognosis were collected.
Results:
Among 622 cases (54.6 % boys), the highest incidence was in 1-year-olds, with case numbers peaking during COVID-19 and influenza outbreaks. The frequency of clinical syndromes was: acute encephalopathy with biphasic seizures and late reduced diffusion, 35.1 %; clinically mild encephalitis/encephalopathy with a reversible splenial lesion, 17.8 %; hemorrhagic shock and encephalopathy syndrome (HSES), 6.9 %; acute encephalitis with refractory, repetitive partial seizures, 3.7 %; acute fulminant cerebral edema (AFCE), 2.2 %; acute necrotizing encephalopathy, 1.6 %; and unclassifiable, 31.4 %. Notably, the combined HSES/AFCE rate increased from 1.9 % in the 2014-2017 survey to 9.1 %, likely due to enhanced diagnosis and COVID-19 impact. Pathogens were exanthem subitum (16.1 %), severe acute respiratory syndrome coronavirus 2 (15.9 %), and influenza (7.7 %). Treatments included steroid pulse therapy (68.9 %), mitochondrial cocktails (42.5 %), and targeted temperature management (31.0 %).
Conclusion:
This study provides a comprehensive overview of pediatric acute encephalopathy during COVID-19 outbreaks, shows increases in the incidence of HSES/AFCE, and presents current treatment.
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