Diagnostic performance of controlled attenuation parameter for predicting steatosis grade in chronic hepatitis B

Background & aims. A novel controlled attenuation parameter (CAP) using the signals acquired by the FibroScan (R) has been developed as a method for evaluating steatosis. The aim of this study is to assess the performance of the CAP for the detection and quantification of steatosis in patients with chronic hepatitis B (CHB). Material and methods. 136 subjects with CHB underwent liver biopsy and FibroScan (R) within 60 days. CAP was evaluated retrospectively using raw FibroScan (R) data. Steatosis was graded as follows: SO (steatosis < 10% of hepatocytes), S1 (10 to < 30%), S2 (30 to < 60%) or S3 (>= 60%). Performance was evaluated by area under the receiver operating characteristic (AUROC) curve. Results. Proportions of each steatosis grade (S0-S3) were 78, 10, 9 and 3%, respectively. Using univariate analysis, liver stiffness measurement (LMS) significantly correlated with fibrosis stage (tau = 0.43; P < 10(-10)), sex, necro-inflammatory activity, steatosis, age, NASH, and perisinusoidal fibrosis, and with liver fibrosis stage (P < 10(-8)) and perisinusoidal fibrosis (P = 0.008) using multivariate analysis. CAP correlated with steatosis (tau = 0.38, P < 10(-7)), body mass index, NASH, fibrosis and perisinusoidal fibrosis using univariate analysis, but only steatosis (P < 10(-10)) and perisinusoidal fibrosis (P = 0.002) using multivariate analysis. AUROCs for LSM were: 0.77 (0.69-0.85), 0.87 (0.80-0.95), and 0.93 (0.83-1.00), respectively, for fibrosis stages F >= 2, F >= 3 and F = 4. AUROCs for CAP were: 0.82 (0.73-0.92), 0.82 (0.69-0.95), and 0.97 (0.84-1.00) for >= S1, >= S2 and S3 steatosis, respectively. Conclusions. In conclusion CAP is a novel, accurate non-invasive tool and may be suitable for detecting and quantifying steatosis in CHB patients.