Precise fibrosis staging with shear wave elastography in chronic hepatitis B depends on liver inflammation and steatosis

Background Two-dimensional shear wave elastography (2D-SWE) is the latest generation of ultrasound elastography for the non-invasive assessment of liver fibrosis in chronic hepatitis B (CHB). We aimed to identify confounders of 2D-SWE in fibrosis grading. Methods A prospective cohort of 440 CHB patients (286 with liver biopsy and 154 with clinical decompensated cirrhosis) was consecutively enrolled from a clinical trial (registration number: ChiCTR-DCD-15006000) aimed at optimizing 2D-SWE assessments from 2015 to 2018. All patients underwent 2D-SWE examination, anthropometric measurement, and serum biomarker assessment. Steatosis was graded by the magnetic resonance imaging-derived proton density fat fraction (MRI-PDFF). Results Overall, the prevalence of incorrect fibrosis staging by 2D-SWE was 26.1% (n = 115), with 43.5% of patients under-staged and 56.5% over-staged. In multivariate analysis, the steatosis degree was an independent predictor of 2D-SWE discordance in the overall cohort, with moderate-severe steatosis for underestimation (odds ratio, [OR] = 4.3, 95% confidence interval [CI] 1.2-18.2, p = 0.049) and overestimation (OR = 8.2, 95% CI 2.9-23.5, p < 0.001), and mild steatosis for overestimation (OR = 3.7, 95% CI 1.5-9.0, p = 0.004). In patients with liver biopsy, both histological inflammation activity over 2 (OR = 5.0, 95% CI 2.0-25.3, p = 0.048) and moderate-severe steatosis (OR = 5.2, 95% CI 2.1-13.4, p < 0.001) were independent factors associated with discordance. For the risk of 2D-SWE mis-staging, a nomogram that integrated these confounders was established and the area under the receiver operating characteristic curve of the model was 0.861. Conclusions Steatosis and inflammation activities were confounders for 2D-SWE. The combination of these confounders could predict mis-staging risks of CHB-related fibrosis with 2D-SWE and may be valuable to decision-making on liver biopsy for fibrosis staging.