Published online Jul 21, 2021. doi: 10.3748/wjg.v27.i27.4358
Peer-review started: January 31, 2021
First decision: May 13, 2021
Revised: May 15, 2021
Accepted: June 22, 2021
Article in press: June 22, 2021
Published online: July 21, 2021
Since it was first reported in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has spread rapidly around the world to cause the ongoing pandemic. Although the clinical manifestations of SARS-CoV-2 infection are predominantly in the respiratory system, liver enzyme abnormalities exist in around half of the cases, which indicate liver injury, and raise clinical concern. At present, there is no consensus whether the liver injury is directly caused by viral replication in the liver tissue or indirectly by the systemic inflammatory response. This review aims to summarize the clinical manifestations and to explore the underlying mechanisms of liver dysfunction in patients with SARS-CoV-2 infection.
Core Tip: The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is one of the most influential emerging infectious diseases worldwide. Accumulating evidence suggests that liver injury is common in COVID-19 patients, and many severe cases tend to be associated with dysregulated liver functions. In this review, we summarize the currently available data of liver enzyme abnormalities in patients confirmed to have COVID-19 and analyze multiple risk factors for liver injury. However, the mechanism of liver impairment seems to be multifactorial. The evidence of direct liver injury triggered by SARS-CoV-2 infection or indirect liver injury induced by overwhelmed cytokine storm will also be discussed.