Primary Versus Secondary NAFLD: Perspective on Advanced Fibrosis

Abstract

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. To determine the histopathological differences between primary and secondary NAFLD and establish whether the prevalence of advanced fibrosis varies between the two types. Three years of retrospective study of 90 liver biopsies with ≥5% macrovesicular steatosis. Age, gender, clinical history, serum transaminaselevels 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. 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. 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.