Clinical relevance of shear wave elastography compared with transient elastography and other markers of liver fibrosis

Abstract

Background: Early and accurate non-invasive diagnosis of liver fibrosis is important for reducing the burden of cirrhosis and related complications.

Aim: This cross-sectional study compares shear wave elastography (SWE), transient elastography (TE) and clinical markers of chronic liver disease in patients with various liver disorders.

Methods: Liver ultrasound with SWE was performed on 421 adult patients, 227 of whom also had TE. Patient age, gender, body mass index (BMI), liver disease aetiology and laboratory results were recorded. Associations between SWE, TE and other tests for liver fibrosis and chronic liver disease severity were sought. Advanced liver fibrosis was defined as liver stiffness measurement (LSM) equivalent to ≥F3 using Metavir staging.

Results: Patients were predominantly male (68%), with mean (standard deviation) age 54 (13) years, BMI 28 (6) kg/m² and serum alanine aminotransferase (ALT) 39 (27) U/L. Liver disorders were predominantly non-alcoholic fatty liver disease (NAFLD), chronic hepatitis B (CHB), chronic hepatitis C (CHC) and alcohol-related liver disease. The median (interquartile range) LSM was 10 (6-20) kPa with SWE and 9.2 (6-21) kPa with TE. Advanced liver fibrosis was associated with older age, higher BMI, model for end-stage liver disease score, aspartate aminotransferase (AST), AST/ALT ratio, AST to platelet ratio index, fibrosis-4 index and Hepascore. SWE and TE LSM were positively correlated, particularly for NAFLD and CHC. SWE LSM predicted ultrasound and endoscopy-diagnosed portal hypertension and oesophageal varices.

Conclusions: Across various liver diseases, SWE is at least comparable with TE and other non-invasive tests of liver fibrosis. SWE is accurate for predicting liver-related portal hypertension.

Keywords: chronic liver disease; elastography; endoscopy; liver fibrosis; portal hypertension; ultrasound.

Figure 1

Relationship between shear wave elastography (SWE) liver stiffness measurement and age, body mass index (BMI) and other risk factors for liver fibrosis. Error bars represent the means and standard deviations. ALT, alanine aminotransferase; APRI, AST to platelet ratio index; AST, aspartate aminotransferase; CI, confidence interval; FIB‐4, fibrosis‐4 index.

Figure 2

Correlations between shear wave elastography and transient elastography liver stiffness measurement (LSM) in different liver disorders: alcohol (r = 0.53, P = 0.03); non‐alcoholic fatty liver disease (NAFLD) (r = 0.87, P < 0.001); hepatitis C virus (HCV) (r = 0.76, P < 0.001); hepatitis B virus (HBV) (r = 0.50, P < 0.001).

Figure 3

Diagnostic ability of various tests for (A) transient elastography (TE) significant fibrosis (≥F2); (B) TE advanced liver fibrosis (≥F3); (C) TE‐diagnosed cirrhosis (F4). Tables display area under the receiver operating characteristics curve (AUROC) and 95% confidence intervals (CI). P‐values compare shear wave elastography (SWE) AUROC with AUROC for Hepascore, fibrosis‐4 index (FIB‐4), AST to platelet ratio index (APRI) and aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio.