FIB-4 for Noninvasive Diagnosis of Hepatic Fibrosis
Non-invasively identify hepatic fibrosis
In Sterling et al, which studied patients co-infected with HIV and Hepatitis C, a simple, non-invasive index (FIB-4) was developed to identify significant hepatic fibrosis.
The formula for FIB-4 is: Age ([yr] x AST [U/L]) / ((PLT [10(9)/L]) x (ALT [U/L])(1/2)).
The AUROC of the index was 0.765 for differentiation between Ishak stage 0-3 and 4-6. At a cutoff of <1.45 in the validation set, the negative predictive value to exclude advanced fibrosis (stage 4-6) was 90% with a sensitivity of 70%. A cutoff of >3.25 had a positive predictive value of 65% and a specificity of 97%. Using these cutoffs, 87% of the 198 patients with FIB-4 values outside 1.45-3.25 would be correctly classified, and liver biopsy could be avoided in 71% of the validation group.
Sterling RK, Lissen E, Clumeck N, et. al.