Published online Jul 7, 2019. doi: 10.3748/wjg.v25.i25.3256
Peer-review started: April 19, 2019
First decision: May 9, 2019
Revised: May 20, 2019
Accepted: June 8, 2019
Article in press: June 8, 2019
Published online: July 7, 2019
Accurate detection of significant fibrosis (fibrosis stage 2 or higher on the METAVIR scale) is important especially for chronic hepatitis B (CHB) patients with high viral loads but with normal or mildly elevated alanine aminotransferase (ALT) levels because the presence of significant fibrosis is accepted as the indication for antiviral treatment. Liver biopsy is the reference standard for diagnosing significant fibrosis, but it is an invasive procedure. Consequently, noninvasive imaging-based measurements, such as magnetic resonance elastography (MRE) or two-dimensional shear-wave elastography (2D-SWE), have been proposed for the quantitative assessment of liver fibrosis.
To explore MRE and 2D-SWE to identify fibrosis stage, and to compare their performance with that of serum-based indices.
The study enrolled 63 treatment-naïve CHB patients with high viral loads but with normal or mildly elevated ALT levels who underwent liver biopsy before a decision was made to initiate antiviral therapy. MRE and 2D-SWE were performed, and serum-based indices, such as FIB-4 and aspartate transaminase to platelet ratio index (APRI), were calculated. The diagnostic performances of MRE, 2D-SWE, FIB-4, and APRI for assessing significant fibrosis (≥ F2) and cirrhosis (F4) were evaluated with liver histology as the reference standard, using receiver operating characteristic analyses.
The liver fibrosis stage was F0/F1 in 19, F2 in 14, F3 in 14, and F4 in 16 patients, respectively. MRE significantly discriminated F2 from F0/1 (P = 0.022), whereas 2D-SWE showed a broad overlap in distinguishing those stages. MRE showed a higher correlation coefficient value with fibrosis stage than 2D-SWE with fibrosis stage (0.869 vs 0.649, Spearman test; P < 0.001). Multivariate linear regression analyses showed that fibrosis stage was the only factor affecting the values of MRE (P < 0.001), whereas body mass index (P = 0.042) and fibrosis stage (P < 0.001) were independent factors affecting 2D-SWE values. MRE performance for diagnosing significant fibrosis was better [area under the curve (AUC) = 0.906, positive predictive value (PPV) 97.3%, negative predictive value (NPV) 69.2%] than that of FIB-4 (AUC = 0.697, P = 0.002) and APRI (AUC = 0.717, P = 0.010), whereas the performance of 2D-SWE (AUC = 0.843, PPV 86%, NPV 65%) was not significantly different from that of FIB-4 or APRI.
Compared to SWE, MRE might be more precise non-invasive assessment for depicting significant fibrosis and for making-decision to initiate antiviral-therapy in treatment-naïve CHB patients with normal or mildly-elevated ALT levels.
Core tip: The present study investigated magnetic resonance elastography (MRE) and two-dimensional shear-wave elastography (2D-SWE) to identify significant fibrosis, and to compare their performance with that of serum-based indices in treatment-naïve chronic hepatitis B (CHB) patients with borderline-normal alanine aminotransferase levels, who should be considered for initiation of antiviral therapy depending on the presence of significant fibrosis. Our data demonstrated that MRE was a more accurate and noninvasive measurement for detecting significant fibrosis, compared to 2D-SWE as well as serum-based indices, and our results suggested that MRE could be used as a basis for anti-HBV treatment-decisions in treatment-naïve CHB patients.