Shear wave elastography in hepatitis C patients before and after antiviral therapy

AIM To investigate shear wave (SW) propagation velocity in patients with untreated hepatitis C and patients with sustained virological response (SVR). METHODS A total of 136 hepatitis C patients [85 patients who had not received antiviral therapy (naïve group) and 51 patients who had received antiviral therapy and subsequently achieved SVR of at least 24 wk (SVR group)] and 58 healthy volunteers and outpatients without liver disease (control group) underwent evaluation of liver stiffness by SW elastography (SWE). Various parameters were evaluated in the chronic hepatitis C patients at the time of SWE. RESULTS SW propagation velocity (Vs) was 1.23 ± 0.14 m/s in the control group, 1.56 ± 0.32 m/s in the SVR group, and 1.69 ± 0.31 m/s in the naïve group. Significant differences were seen between the control group and the SVR group (P = 0.0000) and between the SVR group and the naïve group (P = 0.01417). All four fibrosis markers were higher in the naïve group than in the SVR group. In the naïve group, Vs was positively correlated with alanine aminotransferase (ALT) (r = 0.5372), α feto protein (AFP) (r = 0.4389), type IV collagen (r = 0.5883), procollagen III peptide (P-III-P) (r = 0.4140), hyaluronic acid (r = 0.4551), and Mac-2 binding protein glycosylation isomer (M2BPGi) (r = 0.6092) and negatively correlated with albumin (r = -0.4289), platelets (r = -0.5372), and prothrombin activity (r = -0.5235). On multiple regression analysis, Vs was the most strongly correlated with ALT (standard partial regression std β = 0.4039, P = 0.00000). In the SVR group, Vs was positively correlated with AFP (r = 0.6977), type IV collagen (r = 0.5228), P-III-P (r = 0.5812), hyaluronic acid (r = 0.5189), and M2BPGi (r = 0.6251) and negatively correlated with albumin (r = -0.4283), platelets (r = -0.4842), and prothrombin activity (r = -0.4771). On multiple regression analysis, Vs was strongly correlated with AFP (standard partial regression std β = 0.5953, P = 0.00000) and M2BPGi (standard partial regression std β= 0.2969, P = 0.03363). CONCLUSION In hepatitis C patients, liver stiffness is higher in treatment-naïve patients than in those showing SVR. SWE may be a predictor of hepatocarcinogenesis in SVR patients.