Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 21, 2021; 27(27): 4358-4370
Published online Jul 21, 2021. doi: 10.3748/wjg.v27.i27.4358
Dysregulated liver function in SARS-CoV-2 infection: Current understanding and perspectives
Yi-Ke Huang, Yu-Jia Li, Bin Li, Pan Wang, Qing-Hua Wang
Yi-Ke Huang, Yu-Jia Li, Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Peking Union Medical College, Key Laboratory for Transfusion-transmitted Infectious Diseases of the Health Commission of Sichuan Province, Chengdu 610052, Sichuan Province, China
Yu-Jia Li, Bin Li, Joint laboratory on Transfusion-transmitted Diseases between Institute of Blood Transfusion, Chinese Academy of Medical Sciences and Nanning Blood Center, Nanning 530007, Guangxi Zhuang Autonomous Region, China
Pan Wang, Qing-Hua Wang, Department of Emergency, The Traditional Chinese Medicine Hospital of Wenjiang District, Chengdu 611130, Sichuan Province, China
Author contributions: Huang YK, Li YJ and Li B collected/analyzed data and drafted the manuscript; Wang P and Wang QH concepted and designed the structure of the manuscript and performed critical editing and proof-reading; All authors have read and approve the final manuscript; Wang P and Wang QH contributed equally to this manuscript.
Supported by Sino-German Center for Research Promotion, National Natural Science Foundation of China, No. C-0029; and Health Commission of Chengdu, No. 2020179.
Conflict-of-interest statement: There are no conflicts of interest to declare.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Qing-Hua Wang, MD, Chief Doctor, Department of Emergency, The Traditional Chinese Medicine Hospital of Wenjiang District, No. 156 Dongda Street, Chengdu 611130, Sichuan Province, China.
Received: January 31, 2021
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.

Keywords: SARS-CoV-2, COVID-19, Dysregulated liver function, Cytokine storm

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.