Introduction
COVID-19 was originally identified as a respiratory illness with emerging literature highlighting extrapulmonary manifestations ranging from neurological to dermatological, inclusive of gastrointestinal and hepatobiliary complications. In adult literature, between 10 and 58% of hospitalized patients with COVID-19 have elevated liver enzymes, predominantly transaminitis with aspartate aminotransferase (AST) higher than alanine aminotransferase (ALT). Transaminitis greater than five times the upper limit of normal is uncommon, as are significant elevations in alkaline phosphatase. COVID-19 associated liver injury (known as COVALI) is postulated to result from direct virus-mediated hepatocyte damage via angiotensin converting enzyme-2 (ACE-2) receptor, ischemic/hypoxic bystander injury, cytokine-driven and immune-mediated damage, or antiviral drug-related liver injury. COVALI in adult studies is typically mild and self-limiting.
Medical literature on liver injury associated with COVID-19 in children is more limited and spans from single center cohorts to case reports, covering both respiratory COVID-19 as well as the unique multi-system inflammatory syndrome (MIS-C). A study of 291 patients (220 with COVID-19 and 71 with MIS-C) had an overall rate of elevated ALT of 36%, 31% in COVID-19 cases and 51% in MIS-C cases. Severe liver injury, denoted as ALT > 200 U/L, was noted in 8% of children with COVID-19 and 4% with MIS-C with one child with MIS-C and acute liver failure that recovered(Perez et al. 2021). No matter straightforward COVID-19 or more severe development of MIS-C, those with elevated ALT had more severe disease with higher rates of multisystem organ dysfunction, respiratory failure, and longer hospitalization as well as ICU stay(Perez et al. 2021).
Few case reports have described pediatric patients presenting with acute liver failure in the context of acute COVID-19 infection. While recovery with native liver was the more common outcome, at least one case had a fatal outcome(Sgouropoulou et al. 2021).