Liver fibrosis evaluation using real-time shear wave elastography: Applicability and diagnostic performance using methods without a gold standard

Background & Aims: Real-time shear wave elastography (SWE) is a new two-dimensional transient elastography which had no assessment of factors associated with reliability, and had limited comparisons with other validated fibrosis biomarkers. The aim was to assess the applicability and performances of SWE for the diagnosis of fibrosis as compared with FibroTest (FT) and liver stiffness measurement (LSM) by transient elastography using two probes (TE-M and TE-XL). Methods: Without a gold standard, the strength of concordance, discordance analysis and latent class analysis (LCM) were applied. Results: 422 patients were included. The applicability of SWE (90.0%) was significantly lower than that of FT (97.9%; p <0.0001) and did not differ from those of TE-M (90.5%) and TE-XL (90.3%); it was higher though for SWE (86%) in 22 patients with ascites vs. 55% using TE-M (p = 0.04). For the diagnosis of all fibrosis stages as presumed by FT, the performance of SWE was highly significant (Obuchowski measure 0.807 +/- 0.013 [m +/- se]), but lower than those of TE-M (0.852; p = 0.0007) and TE-XL (0.834; p = 0.046). SWE had a low performance for discrimination between F0 and F1. For the diagnosis of cirrhosis using LCM, SWE specificities were all equal to 99%, and SWE sensitivities ranged from 0.47 to 0.64. For the diagnosis of non-cirrhotic stages, the results were heterogeneous. Conclusions: The performance of SWE for the diagnosis of cirrhosis was similar to those of FT and TE. SWE applicability was lower than that of FT, but greater than that of TE in patients with ascites. (c) 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.