SARS-CoV-2 infection can enhance broad and non-specific immune activation including hyperactivation of the complement[13]. Co-occurrence of SARS-CoV-2 infection may be an exacerbating factor and may be the reason for the high rate of SARS-CoV-2 co-infection
Corticosteroids have been reported to be effective in the treatment of liver injury with AAV vectors. Since all of the current candidate causes are unlikely to be seriously aggravated by short-term corticosteroid administration, a single, short-acting corticosteroid administration and observation of response may be considered at an early stage of diagnosis, given the risk of progression to severe hepatitis. AAV type 2 is difficult to test for in the general hospital setting, and guidelines should be urgently developed for tests that should be performed on acute hepatitis of unknown origin in children. Polymerase Chain Reaction testing for AAV should be performed in both blood and stool, along with adenovirus. In addition, analysis of AAV type 2 capsid-specific T cells by ELISPOT in patients may be the key to elucidating the cause
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