The spontaneous course of liver enzymes and its correlation in nonalcoholic fatty liver disease

Background: The course of liver enzymes and their clinical correlations in nonalcoholic fatty liver disease (NAFLD) remains largely undescribed. Aims: The objective of this study was to determine the spontaneous course of liver enzymes, and the association between changes in liver enzymes with changes in body weight and liver histology in NAFLD. Methods: Follow-up data were prospectively collected for 2 years in 73 untreated patients with NAFLD. Liver enzymes were measured every 3 months, and liver biopsy repeated at 2 years. Results: A significant improvement in serum levels of aminotransferases, alkaline phosphatase, and γ-glutamyl-transferase levels, and a significant decrease in albumin levels occurred with no significant change in body weight over the 2 years. During this period, alanine aminotrans-ferase levels were persistently elevated in 68% of patients, fluctuated between normal and elevated in 22% of patients, and normalized in 10% of patients. There was no clear-cut correlation between the pattern of alanine aminotransferase levels and changes in steatosis, inflammation, hepatocyte ballooning, or fibrosis stage over time. Conclusions: Liver enzyme levels and aminotransferase activity are insensitive tools to follow changes in liver histological features in NAFLD. These data should be taken into consideration in patient counseling and monitoring, and in the design of future therapeutic trials.