FIB-4 index to rule-out advanced liver fibrosis in NAFLD

Last edited 11/2020 and last reviewed 04/2023

The FIB-4 index incorporates routinely available clinical data including age, AST, platelet count (PLT), and ALT level according to Sterling’s formula as follows:

• the scoring system creates a score - <1.45 has a negative predictive value of over 90% for advanced liver fibrosis of multiple aetiologies (1)(2)
• a score of >3.25 has a positive predictive value of 65% for advanced fibrosis with a specificity of 97%
• it has been suggested (3):
• A FIB-4 index<1.45 in a context of fatty liver disease excludes clinically significant hepatic fibrosis
• additional explorations are mandatory to excluded hepatic fibrosis for a a FIB-4 index>1.45 in a context of fatty liver disease
• a complete hepatological workup is mandatory for a FIB-4 index>3.25 in a context of fatty liver disease

Reference:

• Sterling RK, Lissen E, Clumeck N, et. al. Development of a simple noninvasive index to predict significant fibrosis patients with HIV/HCV co-infection. Hepatology 2006;43:1317-1325
• McPherson S, Stewart SF, Henderson E et al. Simple non-invasive fibrosis scoring systems can reliably exclude advanced fibrosis in patients with non-alcoholic fatty liver disease. Gut 2010;59:1265–9 doi:10.1136/gut.2010.216077
• Mallett V et al.FIB-4 index to rule-out advanced liver fibrosis in NAFLD patients. Presse Med 2019 Dec;48(12):1484-1488.