RELATIONSHIP OF FATTY LIVER GRADING ALONG WITH THE LIVER ENZYMES

Abstract

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), is the most common chronic liver disease worldwide. Although liver enzymes are routinely used to assess hepatic injury, their relationship with imaging-based fatty liver grading remains inconsistent. This systematic review aimed to evaluate the association between fatty liver grading and serum liver enzyme levels.

Methods: A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Electronic databases including PubMed/MEDLINE, Scopus, Web of Science, Embase, Google Scholar, and the Cochrane Library were searched for studies published between January 2018 and December 2026. Studies evaluating the relationship between imaging-based fatty liver grading and liver enzyme levels were included. Two reviewers independently screened studies, extracted data, and assessed methodological quality using the Newcastle–Ottawa Scale and the Cochrane Risk of Bias tool. Data were synthesized qualitatively.

Results: A total of 102 records were identified, of which 20 studies met the inclusion criteria. Most studies demonstrated a positive association between increasing fatty liver grade and elevated serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Several intervention studies reported significant reductions in liver enzyme levels following improvements in hepatic steatosis through lifestyle modification, pharmacological therapy, probiotic supplementation, glucose-lowering agents, or bariatric surgery. However, several studies also reported normal liver enzyme values despite moderate-to-severe hepatic steatosis. Elevated gamma-glutamyl transferase (GGT) levels and higher AST/ALT ratios were more frequently associated with advanced liver disease and adverse clinical outcomes.

Conclusion: Liver enzyme abnormalities generally increase with worsening fatty liver grade; however, liver enzymes alone cannot reliably determine the severity of hepatic steatosis. Combining imaging-based fatty liver grading with biochemical liver enzyme assessment provides a more accurate approach for diagnosis, disease monitoring, and prognostic evaluation in patients with fatty liver disease.