Comparison of two-dimensional shear wave elastography, magnetic resonance elastography, and three serum markers for diagnosing fibrosis in patients with chronic hepatitis B: a meta-analysis

Noninvasive diagnosis of liver cirrhosis: qualitative and quantitative imaging biomarkers

A diagnosis of cirrhosis initiates a shift in the management of chronic liver disease and affects the diagnostic workflow and treatment decision of primary liver cancer. Liver biopsy remains the gold standard for cirrhosis diagnosis, but it is invasive and susceptible to sampling bias and observer variability. Various qualitative and quantitative imaging biomarkers based on ultrasound, CT and MRI have been proposed for noninvasive diagnosis of cirrhosis. Qualitative imaging features are easy to apply but have moderate diagnostic sensitivity. Elastography techniques allow quantitative assessment of liver stiffness and are highly accurate for cirrhosis diagnosis. Ultrasound elastography are widely used in clinical practice, while MR elastography has narrower availability. Although not applicable in clinical practice yet, other quantitative imaging features, including liver surface nodularity, linear and volumetric measurement, extracellular volume fraction, liver enhancement on hepatobiliary phase, and parameters derived from diffusion-weighted imaging, can provide additional information of liver morphology, perfusion, and function, thus may increase diagnosis performance. The introduction of radiomics and deep learning has further improved diagnostic accuracy while reducing subjectivity. Several imaging features may also help to assess liver function and outcomes in patients with cirrhosis. In this review, we summarize the qualitative and quantitative imaging biomarkers for noninvasive cirrhosis diagnosis, and the assessment of liver function and outcomes, and discuss the challenges and future directions in this field.

Non-Invasive Assessment of Liver Fibrosis in Hepatitis B Patients

The aim of this review is to provide updated information on the clinical use of non-invasive serum and imaging-based tests for fibrosis assessment in chronic hepatitis B (CHB) virus infection. In recent years, non-invasive tests (NIT) have been increasingly used to determine eligibility for treatment. Liver biopsy is still considered the gold standard for assessing inflammatory activity and fibrosis staging, but it is an invasive procedure with inherent limitations. Simple serum markers such as APRI and FIB-4 are limited by indeterminate results but remain useful initial tests for fibrosis severity if imaging elastography is not available. Point-of-care US-based elastography techniques, such as vibration-controlled transient elastography or 2D shear wave elastography, are increasingly available and have better accuracy than simple serum tests for advanced fibrosis or cirrhosis, although stiffness cut-offs are variable based on E-antigen status and inflammatory activity. Current NITs have poor diagnostic performance for following changes in fibrosis with antiviral therapy. However, NITs may have greater clinical utility for determining prognosis in patients with CHB that have advanced disease, especially for the development of hepatocellular carcinoma and/or liver decompensation. Algorithms combining serum and imaging NITs appear promising for advanced fibrosis and prognostic risk stratification.

FIB-4 and APRI scores for progressive liver fibrosis diagnosis in children with biliary atresia

Introduction

Finding non-invasive methods to predict the degree of liver fibrosis is very important in managing children with biliary atresia. Therefore, we explored the predictive value of APRI, FIB-4, and serological markers for liver fibrosis in children with biliary atresia.

Methods

This study retrospectively reviewed data from children diagnosed with BA between March and December 2022. Liver tissue pathology specimens were obtained during surgery. The serum markers were measured within 2 days before the Kasai procedure or liver transplantation. The aspartate aminotransferase-to-platelet ratio index (APRI) and the four-factor-based fibrosis index (FIB-4) were calculated. The outcome was the diagnosis of progressive liver fibrosis.

Results

This study reviewed the data from 41 children with biliary atresia. APRI had 52% sensitivity and 83% specificity for progressive liver fibrosis, while FIB-4 had 83% sensitivity and 67% specificity. Their areas under the curve were not significantly different from those of conventional markers.

Conclusion

Although they were not better than conventional markers, APRI and FIB-4 can be used as follow-up markers for progressive liver fibrosis in patients with biliary atresia, but their predictive value was moderate. Additional studies are necessary to determine whether they could be combined with other markers to improve their predictive value.

Autoimmune Hepatitis and Fibrosis

Autoimmune hepatitis (AIH) is a chronic immune-inflammatory disease of the liver, generally considered a rare condition. The clinical manifestation is extremely varied and can range from paucisymptomatic forms to severe hepatitis. Chronic liver damage causes activation of hepatic and inflammatory cells leading to inflammation and oxidative stress through the production of mediators. This results in increased collagen production and extracellular matrix deposition leading to fibrosis and even cirrhosis. The gold standard for the diagnosis of fibrosis is liver biopsy; however, there are serum biomarkers, scoring systems, and radiological methods useful for diagnosis and staging. The goal of AIH treatment is to suppress fibrotic and inflammatory activities in the liver to prevent disease progression and achieve complete remission. Therapy involves the use of classic steroidal anti-inflammatory drugs and immunosuppressants, but in recent years scientific research has focused on several new alternative drugs for AIH that will be discussed in the review.

Current Best Practice in Hepatitis B Management and Understanding Long-term Prospects for Cure

The hepatitis B virus (HBV) is a major cause of cirrhosis and hepatocellular carcinoma worldwide. Despite an effective vaccine, the prevalence of chronic infection remains high. Current therapy is effective at achieving on-treatment, but not off-treatment, viral suppression. Loss of hepatitis B surface antigen, the best surrogate marker of off-treatment viral suppression, is associated with improved clinical outcomes. Unfortunately, this end point is rarely achieved with current therapy because of their lack of effect on covalently closed circular DNA, the template of viral transcription and genome replication. Major advancements in our understanding of HBV virology along with better understanding of immunopathogenesis have led to the development of a multitude of novel therapeutic approaches with the prospect of achieving functional cure (hepatitis B surface antigen loss) and perhaps complete cure (clearance of covalently closed circular DNA and integrated HBV DNA). This review will cover current best practice for managing chronic HBV infection and emerging novel therapies for HBV infection and their prospect for cure.

Serum Fibroblast Growth Factor 19 as a Biomarker in Hepatitis B Virus-Related Liver Disease

Background: Past research has found that fibroblast growth factor 19 (FGF19) is associated with several hepatic disorders, such as alcoholic liver disease and primary biliary cirrhosis. However, there is currently a lack of relevant studies on the relationship between FGF19 and hepatitis B virus (HBV)-related liver disease. Objectives: This study aimed to assess the role of serum FGF19 as a new biomarker for HBV-related liver disease and provide scientific data to show the clinical value of this biomarker. Methods: A retrospective study included 37 patients with chronic hepatitis B (CHB), 33 patients with HBV-related cirrhosis (HBV-cirrhosis), and 32 patients with HBV-related hepatocellular carcinoma (HBV-HCC). Furthermore, 33 normal people were randomly selected as healthy controls. The serum levels of FGF19 were measured by ELISA. Results: Serum FGF19 levels were increased sequentially in the CHB group, HBV-cirrhosis group, and HBV-HCC group. Furthermore, serum FGF19 levels positively correlated with alpha-fetoprotein, prothrombin time, international normalized ratio, total bilirubin, direct bilirubin, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl-transferase, alkaline phosphatase, total bile acid, serum markers for liver fibrosis, ascites, cirrhosis, Child-Pugh classification and model for end-stage liver disease sodium (MELD-Na) score, while negatively correlated with platelet count, prothrombin activity, and albumin. The diagnostic threshold of serum FGF19 for HBV-related HCC was 165.32 pg/mL, with a sensitivity of 81.25% and specificity of 58.57%. Conclusions: Serum FGF19 levels are positively associated with cholestasis, hepatocyte damage, and liver fibrosis but negatively correlated with liver synthetic function and liver functional reserve in HBV-related liver disease. Diverse changes in serum FGF19 may be used as a predictive marker for the progression of HBV-related liver disease. In addition, serum FGF19 has a potential role in monitoring carcinogenesis in patients with HBV-related liver disease.

Diagnostic Performance of Transient Elastography Versus Two-Dimensional Shear Wave Elastography for Liver Fibrosis in Chronic Viral Hepatitis: Direct Comparison and a Meta-Analysis

Objective. This systematic review and meta-analysis aimed to compare the diagnostic performance of transient elastography (TE) and two-dimensional shear wave elastography (2D-SWE) for staging liver fibrosis in patients with chronic viral hepatitis (CVH). Methods. Pubmed, Embase, Web of Science, and Cochrane Library were searched (-01/08/2021) for studies comparing TE with 2D-SWE in patients with CVH. Other etiologies of chronic liver disease (CLD) and articles not published in SCI journals were excluded. The bivariate random-effects model was used to pool the performance of the TE and 2D-SWE. Results. Eight articles with a total of 1301 CVH patients were included. The prevalence of significant fibrosis ( $\text{fibrosis}\text{stage}\ge 2$ ), advanced fibrosis ( $\text{fibrosis}\text{stage}\ge 3$ ), and cirrhosis was 50.8%, 44.8%, and 34.7%, respectively. 2D-SWE expressed higher overall accuracy than TE in detecting significant fibrosis (0.93 vs. 0.85, $P=0.04$ ). No significant difference among the overall diagnostic accuracy of TE and 2D-SWE in staging advanced fibrosis and cirrhosis was found. Conclusion. TE and 2D-SWE express good to excellent diagnostic accuracies to stage fibrosis in CVH patients. 2D-SWE compares favorably with TE especially for predicting significant fibrosis.

Aspartate Aminotransferase to Platelet Ratio Index and Fibrosis-4 Index for Detecting Liver Fibrosis in Patients With Autoimmune Hepatitis: A Meta-Analysis

Background

Aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis-4 index (FIB-4) are the two most widely studied noninvasive markers of liver fibrosis. We aimed to assess the diagnostic accuracy of APRI and FIB-4 for liver fibrosis in patients with autoimmune hepatitis (AIH) using liver biopsy as the reference standard.

Methods

PubMed, EMBASE, Cochrane Library and Web of Science databases were searched for studies (published as of May 1st, 2021) that assessed the diagnostic performance of APRI and FIB-4 for liver fibrosis in AIH. The summary area under receiver operating characteristics curve (AUROC), sensitivity, specificity, diagnostic odds ratios were used to assess the diagnostic accuracy of APRI and FIB-4 for detecting liver fibrosis.

Results

Fourteen studies (including 1015 patients) were selected with 13 studies each evaluating the use of APRI and FIB-4 for detecting different stages of fibrosis in AIH. For prediction of significant fibrosis, advanced fibrosis, and cirrhosis, the summary AUROC value was 0.66 [95% confidence interval (CI): 0.61-0.70], 0.71 (95% CI: 0.67-0.75), and 0.75 (95% CI: 0.71-0.79) for APRI, and the summary AUROC value was 0.75 (95% CI: 0.71-0.79), 0.73 (95% CI: 0.69-0.77) and 0.79 (95% CI: 0.75-0.82) for FIB-4, respectively. The summary sensitivity and specificity for diagnosis of significant fibrosis, advanced fibrosis, and cirrhosis were 90% and 36%, 78% and 55%, and 77% and 61% for APRI, and 70% and 70%, 65% and 70%, and 78% and 65% for FIB-4, respectively.

Conclusions

APRI and FIB-4 showed suboptimal diagnostic performance for identifying liver fibrosis in AIH with mediocre sensitivity and specificity.

Quantitative Assessment of Portal Hypertension by Two-Dimensional Shear Wave Elastography in Rat Models of Nonalcoholic Fatty Liver Disease: Comparison With Four Composite Scores

Background

Measurement of hepatic venous pressure gradients is the gold standard for assessing portal hypertension (PH) but is invasive with potential complications. We aimed to assess the performance in liver and spleen stiffness measurement (LSM and SSM, respectively) by two-dimensional shear wave elastography (2D-SWE) and composite scores including liver stiffness-spleen diameter to platelet ratio score (LSPS), platelet (PLT) count/spleen diameter ratio (PSR), aspartate aminotransferase (AST)/alanine aminotransferase ratio (AAR), and AST-to-PLT ratio index (APRI) for diagnosing PH in nonalcoholic fatty liver disease (NAFLD) rat models.

Methods

Animal models with PH in NAFLD were established in 65 rats, which then underwent 2D-SWE measurements. Morphological and biological parameters were collected for calculation of four composite scores. Correlations of noninvasive methods with portal venous pressure were evaluated by Spearman correlation analysis. The area under the receiver operating characteristic curve (AUC) was used to assess the performance of noninvasive methods in predicting PH.

Results

LSM and SSM were significantly associated with portal venous pressure (r = 0.636 and 0.602, respectively; all P < 0.001). The AUCs of LSM and SSM in the diagnosis of PH were 0.906 (95% confidence interval [CI]:0.841–0.97) and 0.87 (95% CI:0.776–0.964), respectively, and were significantly higher than those in composite scores. The AUCs for LSPS, PSR, AAR, and APRI were 0.793, 0.52, 0.668, and 0.533, respectively, for diagnosing PH. The AUCs of the combined models of LSM and SSM, LSM and PLT, SSM and PLT, and LSM, SSM and PLT were 0.923, 0.913, 0.872, and 0.923, respectively. The four combined models showed no statistical differences compared to LSM and SSM in evaluating PH (all P > 0.05).

Conclusions

LSM and SSM by 2D-SWE can be used as promising noninvasive parameters for diagnosing PH in NAFLD and have higher accuracy than composite scores. The combined models, compared to LSM and SSM, did not significantly improve the performance in diagnosing PH.

Liver fibrosis quantification

Liver fibrosis (LF) is the wound healing response to chronic liver injury. LF is the endpoint of chronic liver disease (CLD) regardless of etiology and the single most important determinant of long-term liver-related clinical outcomes. Quantification of LF is important for staging, to evaluate response to treatment and to predict outcomes. LF is traditionally staged by liver biopsy. However, liver biopsy is invasive and suffers from sampling errors when biopsy size is inadequate; therefore, non-invasive tests (NITs) have found important roles in clinical care. NITs include simple laboratory-based serum tests, panels of serum tests, and imaging biomarkers. NITs are validated against the liver biopsy and will be used in the future for evaluation of nearly all CLDs with invasive liver biopsy reserved for some cases. Both serum tests and some imaging biomarkers such as elastography are currently used clinically as surrogate markers for LF. Several other imaging biomarkers are still considered research and awaiting clinical application in the future. As the evaluation of imaging biomarkers will likely become the norm in the future, understanding pathogenesis of LF is important. Knowledge of properties measured by imaging biomarkers and its correlation with LF is important to understand the application of NITs by abdominal radiologists. In this review, we present a brief overview of pathogenesis of LF, spatiotemporal evolution of LF in different CLD, and severity assessment with liver biopsy. This will be followed by a brief discussion on properties measured by imaging biomarkers and their relationship to the LF.

OUP accepted manuscript

Background

This study aimed to assess the performance of transient elastography (TE), two-dimensional shear wave elastography (2D-SWE), and magnetic resonance elastography (MRE) for staging significant fibrosis and cirrhosis in untreated chronic hepatitis B (CHB) patients.

Methods

Pubmed, Embase, Web of Science, and Cochrane Library were searched for terms involving CHB, TE, 2D-SWE, and MRE. Other etiologies of chronic liver disease, previous treatment in patients, or articles not published in SCI journals were excluded. Hierarchical non-linear models were used to evaluate the diagnostic accuracy of TE, 2D-SWE, and MRE. Heterogeneity was explored via analysis of threshold effect and meta-regression.

Results

Twenty-eight articles with a total of 4,540 untreated CHB patients were included. The summary areas under the receiver-operating characteristic curves (AUROCs) using TE, 2D-SWE, and MRE for predicting significant fibrosis (SF) were 0.84, 0.89, and 0.99, respectively. The AUROC values of TE, 2D-SWE, and MRE for staging cirrhosis were 0.9, 0.94, and 0.99, respectively. Based on the meta-analysis of studies with head-to-head comparison, 2D-SWE is superior to TE (0.92 vs 0.85, P < 0.01) in staging significant fibrosis.

Conclusion

TE, 2D-SWE, and MRE express acceptable diagnostic accuracies in staging significant fibrosis and cirrhosis in untreated CHB patients. 2D-SWE outperforms TE in detecting significant fibrosis in treatment-naive people with hepatitis B virus.

Evaluation of liver fibrosis using hepatic extracellular volume fraction by contrast-enhanced computed tomography before and after direct-acting antiviral therapy in patients with chronic hepatitis C infection: comparison with serological liver fibrosis markers

OBJECTIVE

To evaluate time-dependent changes in hepatic extracellular volume (ECV) fraction using contrast-enhanced CT (CECT) and serological liver fibrosis markers, the fibrosis-4 (FIB-4) index and aspartate aminotransferase to platelet ratio index (APRI), before and after direct-acting antiviral therapy (DAA) for hepatitis C virus (HCV) infection.

METHODS

41 HCV-infected patients who achieved sustained virological response (SVR) after DAA (SVR group) and 10 control patients (untreated or unresponsive to treatment) who underwent CECT and serum biochemical tests before or after the first examination/DAA (T1) and at intervals thereafter (T2:<6 months after T1, T3: at 6-12 months, T4: at 12-24 months, and T5:>24 months) were evaluated.

RESULTS

In the control group, ECV fractions remained relatively unchanged through the study, and significant differences in FIB-4 index comparisons and APRI comparisons were only seen between the T2 and T4 values (p = 0.046 and p = 0.028, respectively). In the SVR group, ECV fractions were significantly different between T1 and T4 and T1 and T5 (p = 0.046 and 0.022, respectively), and both FIB-4 index and APRI were significantly different between T1 and all other time points (p = 0.017 to p < 0.001 and p = 0.001 to p < 0.001, respectively).

CONCLUSION

After DAA, ECV fraction decreased slowly, suggesting an improvement in hepatic fibrosis, while serological liver fibrosis markers decreased immediately, probably due to improvement in hepatic inflammation.

ADVANCES IN KNOWLEDGE

ECV fraction has the potential to be a non-invasive biomarker for the assessment of liver fibrosis after direct-acting antiviral therapy.