Diagnostic performance of FibroTest-ActiTest, transient elastography, and the fibrosis-4 index in patients with autoimmune hepatitis using histological reference.

Background: Noninvasive tests are crucial for the management and follow-up of patients with autoimmune hepatitis, but their validation is limited because of insufficient data.

Aim: To investigate the diagnostic performance of three fibrosis noninvasive tests [FibroTest, vibration-controlled transient elastography (VCTE), and the fibrosis-4 index (FIB-4) and two activity biomarkers (alanine aminotransferase (ALT) and ActiTest].

Methods: This study enrolled 103 patients for whom liver biopsy, hepatic elastography results, and laboratory markers were available. Diagnostic performance was assessed with receiver operating characteristic (ROC) curves, the Obuchowski measure (OM), and the Bayesian latent class model.

Results: FibroTest and VCTE outperformed FIB-4 in cases of significant fibrosis (≥ F2), with areas under the ROC curve of 0.83 [95% confidence interval (CI): 0.73-0.90], 0.86 (95%CI: 0.77-0.92), and 0.71 (95%CI: 0.60-0.80), respectively. The mean (standard error) OM values were 0.92 (0.01), 0.93 (0.01), and 0.88 (0.02) for FibroTest, VCTE, and FIB-4, respectively; FibroTest and VCTE performed comparably, and both were superior to FIB-4 (P = 0.03 and P = 0.005). The areas under the ROC curve values for activity biomarkers were 0.86 (95%CI: 0.76-0.92) for ActiTest and 0.84 (95%CI: 0.73-0.90) for ALT (P = 0.06). The OM values for ActiTest and ALT were 0.92 (0.02) and 0.90 (0.02), respectively (P = 0.005).

Conclusion: FibroTest and VCTE outperformed FIB-4 according to the OM. FibroTest-ActiTest facilitated the evaluation of both fibrosis and activity.