The role of serum bile acid profile in differentiation between nonalcoholic fatty liver disease and chronic viral hepatitis

Abstract

Background: Bile acids are essential organic molecules synthesized from cholesterol in the liver. They have been utilized as indicators of hepatobiliary impairment because synthesis of BAs and their metabolism are influenced by liver diseases. We aimed to investigate the role of serum bile acid level and composition in differentiation between nonalcoholic fatty liver disease (NAFLD) and chronic viral hepatitis. An ultra-performance liquid chromatography coupled with mass spectrometry assay was used to measure the serum level of 14 bile acids in chronic viral hepatitis and NAFLD patients beside normal healthy control subjects. Results: The mean serum levels of 11 out of the 14 bile acids (two primary, six conjugated, and three secondary) were significantly higher in viral hepatitis compared to control. Only 4 bile acids [2 primary, one glycine conjugated (GCDCA), and one secondary (LCA)] had statistically significant increase in their mean serum bile acid level in NAFLD compared to control. Comparing viral hepatitis group against NAFLD group revealed that the mean serum levels of five conjugated and one secondary bile acid (DCA) were significantly higher in viral hepatitis group. Receiver operating characteristic (ROC) curve analysis revealed that LCA had the best diagnostic performance for viral hepatitis followed by TCA and GCDCA. ROC curve for the combined three parameters had better sensitivity and specificity (70.55% and 94.87% respectively). Conclusion: BA compositions including primary, secondary, and conjugated ones could differentiate between chronic viral hepatitis and NAFLD patients, and they might be potential distinguishing biomarkers for this purpose.