Diagnostic value of biochemical markers (FibroTest-FibroSURE) for the prediction of liver fibrosis in patients with non-alcoholic fatty liver disease

Background: Liver biopsy is considered as the gold standard for assessing non-alcoholic fatty liver disease (NAFLD) histologic lesions. The aim of this study was to determine the diagnostic utility of non-invasive markers of fibrosis, validated in chronic viral hepatitis and alcoholic liver disease ( FibroTest, FT), in patients with NAFLD. Methods: 170 patients with suspected NAFLD were prospectively included in a reference center ( Group 1), 97 in a multicenter study ( Group 2) and 954 blood donors as controls. Fibrosis was assessed on a 5 stage histological scale validated by Kleiner et al from F0 = none, F1 = perisinusoidal or periportal, F2 = perisinusoidal and portal/periportal, F3 = bridging and F4 = cirrhosis. Histology and the biochemical measurements were blinded to any other characteristics. The area under the ROC curves (AUROC), sensitivity ( Se), specificity (Sp), positive and negative predictive values (PPV, NPV) were assessed. Results: In both groups FT has elevated and not different AUROCs for the diagnosis of advanced fibrosis (F2F3F4): 0.86 (95% CI 0.77 - 0.91) versus 0.75 ( 95% CI 0.61 - 0.83; P = 0.10), and for F3F4: 0.92 ( 95% CI 0.83 - 0.96) versus 0.81 ( 95% CI 0.64 - 0.91; P = 0.12) in Group1 and Group 2 respectively. When the 2 groups were pooled together a FT cutoff of 0.30 had a 90% NPV for advanced fibrosis ( Se 77%); a FT cutoff of 0.70 had a 73% PPV for advanced fibrosis ( Sp 98%). Conclusion: In patients with NAFLD, FibroTest, a simple and non-invasive quantitative estimate of liver fibrosis reliably predicts advanced fibrosis.