Diagnostic value of Transient Elastography (Fibroscan) in the evaluation of liver fibrosis in chronic viral hepatitis C: Comparison to liver biopsy

Purpose: To assess the Transient Elastography diagnostic and staging role in liver fibrosis in chronic hepatitis C in comparison to hepatic biopsy. Material and methods: 70 chronic viral hepatitis C patients who are candidate for therapy using antiviral drugs underwent Transient Elastography and percutaneous hepatic biopsy on the same day. Measurements of liver stiffness obtained by Fibroscan were correlated with different histological stages of fibrosis. The diagnostic yield of the measurements obtained by Fibroscan were compared to histolopathological stage of fibrosis (Metavir score) to achieve the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) as well as Kappa test. Receiver operating characteristic (ROC) curves were analyzed. Results: There was a correlation between Fibroscan measurements and histological fibrosis stage (r = 0.87, p < 0.001). The Area under the curve (AUC for detection of fibrosis (≥ F1) was 0.91 with a sensitivity, specificity, PPV and NPV of 88%, 77.8%, 96.4% and 50.0% respectively while kappa test and p-value were 0.53 and <0.001 respectively at cut off value of 4.95 kPa. The AUC for fibrosis (≥ F2) was 0.93 with a sensitivity, specificity, PPV, NPV, kappa test and ρ-value 92.0%, 65.7%, 76.1%, 87.5%, 0.59 and <0.001 respectively at cut off value of 6.25 kPa. The AUC for sever fibrosis (≥ F3) was 0.97 with a sensitivity, specificity, PPV, NPP, kappa test and p-value 95%, 89.2%, 80.0%, 97.5%, 0.80 and <0.001 respectively at cut off value of 10.1 kPa. For cirrhosis (=F4) the AUC was 0.98 with a sensitivity, specificity, PPV, NPV, kappa test and p-value 91.7%, 98.3%, 91.7%, 98.5%, 0.89 and <0.001 respectively at cut off value of 17.15 kPa. Conclusion: Transient Elastography is a useful diagnostic method with significantly higher correlation with the liver fibrosis histological grade which is a crucial factor in proper management