Changes in liver function tests caused by COVID-19 and impact on patient outcome: A systematic review

Abstract

Introduction: In March 2020, the World Health Organization declared COVID-19, a disease caused by SARS-CoV-2 infection, a global pandemic. This virus uses human angiotensin-converting enzyme 2 (ACE2) as its receptor for entry. ACE2 is found in pulmonary, cardiac, gastrointestinal, hepatic, renal and vascular tissues, thus posing a potential risk for multisystemic involvement. The excessive release of inflammatory cytokines in COVID-19, as well as the use of medicines with hepatotoxic potential for the treatment of its symptoms, can damage the liver. Objective: To analyze the relationship between changes in liver function tests caused by SARS-CoV-2 infection and their impact on patient prognosis. Methodology: This is a systematic review of stu-dies selected from the PMC, LILACS and SciELO databases. After applying the inclusion and exclusion criteria, 30 articles were included in the final sample for analysis. Results: Elevated AST (aspartate aminotransferase) enzyme levels were reported most frequently and were found in 4 695 cases, while ALT (alanine aminotrans-ferase) elevation was described in 3 226 cases. It was observed that patients with digestive symptoms were more likely to present hepatocellular damage and, consequently, enzymatic alterations. Furthermore, 28.9 % of individuals with impaired liver function died, compared to 9 % of patients with normal function. Conclusion: It is evident that there is a relationship between liver involvement in COVID-19 and mortality. However, there is still a limitation in the number and, more importantly, the homogeneity of the research that performed this assessment.