COVID-19 and liver injury: Pathophysiology, risk factors, outcome and management in special populations

Abstract

The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 is an ongoing health concern. In addition to affecting the respiratory system, COVID-19 can potentially damage other systems in the body, leading to extra-pulmonary manifestations. Hepatic manifestations are among the common consequences of COVID-19. Although the precise mechanism of liver injury is still questionable, several mechanisms have been hypothesized, including direct viral effect, cytokine storm, hypoxic-ischemic injury, hypoxia-reperfusion injury, ferroptosis, and hepatotoxic medications. Risk factors of COVID-19-induced liver injury include severe COVID-19 infection, male gender, advanced age, obesity, and underlying diseases. The presentations of liver involvement comprise abnormalities in liver enzymes and radiologic findings, which can be utilized to predict the prognosis. Increased gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase levels with hypoalbuminemia can indicate severe liver injury and anticipate the need for intensive care units’ hospitalization. In imaging, a lower liver-to-spleen ratio and liver computed tomography attenuation may indicate a more severe illness. Furthermore, chronic liver disease patients are at a higher risk for severe disease and death from COVID-19. Nonalcoholic fatty liver disease had the highest risk of advanced COVID-19 disease and death, followed by metabolic-associated fatty liver disease and cirrhosis. In addition to COVID-19-induced liver injury, the pandemic has also altered the epidemiology and pattern of some hepatic diseases, such as alcoholic liver disease and hepatitis B. Therefore, it warrants special vigilance and awareness by healthcare professionals to screen and treat COVID-19-associated liver injury accordingly.

Keywords: SARS-CoV-2; COVID-19; Liver injury; Chronic liver disease; Management; Liver transplant

Core Tip: Severe acute respiratory syndrome coronavirus-2 can involve the liver and cause damage through different mechanisms. Liver injury can be diagnosed based on alterations in the liver function tests, which can also predict the disease severity and fatality. In patients without underlying liver disease, liver injury is typically mild and can be treated with supportive care. However, it requires additional awareness and appropriate therapy in patients with chronic liver diseases, including autoimmune hepatitis, viral hepatitis, liver cirrhosis, liver transplantation, and nonalcoholic fatty liver disease, which we have discussed in detail.