Hepatitis of unknown etiology in children: Current evidence and association

Two years after the coronavirus disease 2019 (COVID-19) pandemic, acute hepatitis of unknown etiology in children (AHUCD) began to be reported worldwide. The novel coronavirus and adenovirus were found in pathogen and antibody tests in AHUCD cases reported by the World Health Organization. Children are not exposed to the viruses that children are generally exposed to owing to COVID-19 infection preventive measures such as isolation and wearing masks; therefore, some researchers have speculated that this disease is related to reduced exposure to pathogens. Some scientists have also speculated that the disease is related to liver injury and adenoviral hepatitis, which are the sequelae of COVID-19. Some evidence also suggests a weak association between the disease and COVID-19 vaccination. Therefore, further research and investigation of the pathogenesis, preventive measures, and early treatment of hepatitis of unknown etiology are required. This study aimed to synthesize available evidence to further elucidate this disease in order to treat and prevent it effectively.