COVID-19 and the Liver: A 2021 Update

Catherine W. Spearman; Alessio Aghemo; Luca Valenti; Mark W. Sonderup


Liver International. 2021;41(9):1988-1998. 

In This Article

Approach to Abnormal Liver Enzymes in COVID-19 Patients

Patients admitted to hospital with moderate-to-severe disease should have baseline liver tests including ALT, AST, GGT, ALP and bilirubin. Liver enzymes should be monitored as COVID-19 progresses. The aetiology of deranged liver enzymes is invariably multifactorial in the COVID-19 setting. Acute or chronic viral hepatitis and potential hepatotoxins such as statins, azithromycin, lopinavir/ritonavir, remdesivir, tocilizumab, enoxaparin and paracetamol need to be excluded. A direct cytopathic effect on hepatocytes of SARS-CoV-2 is possible as the virus has been isolated from the liver.[46] Furthermore, mitochondrial proteins may directly interact with the virus, which may explain the frequent AST predominance observed.[50] Lastly, the pro-inflammatory response enabling the cytokine storm (IL-2, IL-6, IL-7, GM-CSF, IP-10, MCP-1, MIP-1α, TNF-α) further exacerbated by intrahepatic cytotoxic T cells and Kupffer cell activation contributes to liver enzyme derangement. Myocarditis or skeletal muscle myositis can accentuate the AST levels and warrants consideration in those with disproportionately elevated AST levels.