Primary Versus Secondary NAFLD: Perspective on Advanced Fibrosis

J Clin Exp Hepatol. 2021 Sep-Oct;11(5):557-564. doi: 10.1016/j.jceh.2020.12.009. Epub 2020 Dec 31.

Abstract

Background: The presence of macrovesicular steatosis on liver biopsy is the commonest histopathological finding. Nonalcoholic fatty liver disease (NAFLD) is the presence of ≥5% macrovesicular steatosis without significant alcohol use. It is subdivided into primary and secondary NAFLD; information on their differences is limited.

Aim: To determine the histopathological differences between primary and secondary NAFLD and establish whether the prevalence of advanced fibrosis varies between the two types.

Methodology: Three years of retrospective study of 90 liver biopsies with ≥5% macrovesicular steatosis. Age, gender, clinical history, serum transaminase levels were noted. The biopsy was reviewed for steatosis, inflammation, and fibrosis. Differences between primary and secondary NAFLD for age, gender, AST/ALT ratio, histopathological features were determined. Descriptive statistical analysis, 2-tailed Student's t test, Chi-square test, Fisher's exact test were used, where p < 0.05 was considered significant.

Result: Primary and secondary NAFLD were 42 (46.7%) and 48 (53.3%), respectively. Inflammation was noted in 50 (55.5%) and fibrosis in 31 (34.4%). The prevalence of advanced fibrosis was 24.4%. Primary and secondary NAFLD differed significantly on ballooning degeneration, Mallory Denk bodies (MDBs), glycogenated nuclei, and fibrosis stage (p < 0.05). There were no significant differences among AST/ALT ratio, steatosis, and inflammation grade.

Conclusion: Primary NAFLD is a more severe type of liver disease. On histopathology, ballooning degeneration, MDBs, glycogenated nuclei, and advanced fibrosis was more prevalent in primary than secondary NAFLD.

Keywords: ALT, Alanine aminotransferase; AST, Aspartate aminotransferase; HBV, Hepatitis B virus; HCC, Hepatocellular carcinoma; HIV, Human immunodeficiency virus; MDB, Mallory hyaline bodies; MTX, Methotrexate; NAFLD, Nonalcoholic fatty liver disease; NAS, NAFLD activity score; NASH, Nonalcoholic steatohepatitis; advanced fibrosis; inflammation; non-alcoholic fatty liver disease; primary NAFLD; secondary NAFLD.