Fibrosis assessment in patients with HCV or HBV chronic infection

Meanwhile, measurement of liver stiffness (LS) is the standard for fibrosis screening in patients with chronic hepatitis C virus (HCV) and chronic hepatitis B virus (HBV), namely for the diagnosis of severe fibrosis and cirrhosis (F3 or F4 according to the METAVIR scoring system, respectively) and for the exclusion of significant fibrosis. LS values can be influenced by the degree of necroinflammation in both HBV and HCV infection. In particular, the international guidelines suggest considering normal ALT versus elevated ALT (5 × ULN) in the measurement of LS in HBV-infected patients. Several studies were performed using transient elastography to evaluate its reliability in defining the presence of portal hypertension and esophageal varices. A wide range of cut-off levels have been reported to date. LS is also a strong pre-treatment predictor with regard to the response to antiviral treatment. The precise distinction between advanced fibrosis and cirrhosis is of fundamental importance in terms of both diagnostic and therapeutic approaches. Regression of fibrosis has been demonstrated in patients with HCV after virus elimination and in patients with HBV during antiviral treatment. In HCV patients, a sustained virological response was accompanied by a significant improvement in hepatic function and a decrease of LS. In HBV patients, pre-treatment and LS changes during nucleoside/nucleotide analogues can predict liver-related events. In conclusion, LS measurement has become essential for the clinical management of patients with HCV and HBV chronic infection.