Abstract and Introduction
Hepatitis delta virus (HDV) infection is associated with accelerated progression of liver disease to cirrhosis. Shear wave elastography (SWE) is a non-invasive evaluation method of liver fibrosis. Its performance in accurately characterizing HDV fibrosis compared to other noninvasive markers remains unknown. We assessed the performance of SWE in patients with chronic HDV, Hepatitis B (HBV) and Hepatitis C (HCV) infection. Cirrhosis was determined by histology or clinical data. Area under receiver operator characteristics (AUROC) was used to assess diagnostic performance in identifying cirrhosis by SWE in comparison with Fibroscan® (VCTE) and serologic tests of fibrosis. 158 patients with chronic hepatitis (HDV:44%, HBV: 46% and HCV: 29%) were evaluated. Cirrhosis was diagnosed in 28 (17.7%) patients. Mean noninvasive fibrosis measurements for the HBV/HCV and HDV groups, respectively, were as follows: APRI: 0.73 ± 1.08 and 1.3 ± 1.38; FIB-4: 1.90 ± 2.24 and 2.33 ± 2.24; VCTE: 8.9 ± 6.7 kPa vs 10.4 ± 5.3 kPa; SWE: 1.5 ± 0.2 m/s and 1.6 ± 0.2 m/s. The performance of SWE in detecting HDV-induced cirrhosis (AUROC 0.84, 95% CI 0.71–0.97) was slightly lower than in HBV/HCV induced disease (AUROC 0.88, 95% CI 0.81–0.96). For HDV patients, the performance of SWE was comparable to VCTE and slightly better than APRI and FIB-4 especially in APRI and FIB-4 indeterminate zones. The overall less accurate performance of noninvasive markers in HDV in comparison with HBV and HCV may be a result of significant hepatic inflammation in HDV.
Hepatitis Delta virus (HDV) infection is the most devastating chronic viral liver disease known to humans. It leads to a chronic unremitting inflammation in the hepatic parenchyma whose consequences include fibrosis leading up to cirrhosis and hepatocellular carcinoma (HCC). Unlike the much more common chronic hepatitis B virus (HBV) mono-infection and chronic hepatitis C virus (HCV) infection, the catastrophic end results of HDV infection arrive much sooner and more frequently. Despite multiple attempts at finding an effective and durable treatment regimen for HDV, to this day HDV is considered an incurable disease that has no approved treatment other than the recent conditional approval of bulevirtide by the European Medicine Agency (EMA). While clinical trials attempting to find a cure for HDV are ongoing, proper disease stratification of patients has become imperative as the status of advanced liver fibrosis or cirrhosis will determine the patient's eligibility for trial participation as well as clinical management.
Noninvasive markers of liver fibrosis are commonly used in clinical practice for the evaluation of patients with viral hepatitis. They include the laboratory-based aspartate aminotransferase (AST) to Platelet Ratio Index (APRI) and Fibrosis-4 (FIB-4) score as well as the imaging-based modalities vibration controlled transient elastography (VCTE, Fibroscan®) and shear wave elastography (SWE). SWE is a relatively newer ultrasound (US)-based modality to evaluate fibrosis in the hepatic parenchyma. Unlike the 1-dimensional VCTE which is performed without direct image guidance, in the 2-dimensional SWE, multiple acoustic radiation force impulse (ARFI) measurements are performed on multiple visible points of interest in the hepatic parenchyma in order to estimate shear wave speed. Real-time US imaging allows avoidance of large masses and blood vessels and thus improves measurement accuracy. While all mentioned noninvasive biomarkers have been used extensively and successfully to evaluate fibrosis in HBV and HCV,[9–11] their profile in HDV is different. While VCTE was found to be a reliable test in determining cirrhosis, both APRI and FIB-4 were found to have low-performance accuracy in cirrhosis determination. Data regarding the performance of SWE in the evaluation of fibrosis due to HDV are currently unavailable.
In this study, we set out to compare the performance of SWE in chronic HDV-infected patients to the performance of other available noninvasive markers for the detection of cirrhosis. We also compared our findings in HDV to a cohort of patients infected with either HBV or HCV where the performance of SWE, VCTE and serologic tests of fibrosis was already evaluated.
J Viral Hepat. 2022;29(12):1127-1133. © 2022 Blackwell Publishing