Factors associated with unreliable liver stiffness measurement and its failure with transient elastography in the Chinese population

Determining the ideal measurement site and respiratory condition for liver transient elastography: toward clinical practice standardization

OBJECTIVES

Liver transient elastography (TE) has been endorsed by the WHO as the first-line diagnostic tool for liver diseases. Although unreliable and invalid results caused by intercostal space (ICS)-associated factors (including excessive subcutaneous fat and a narrow ICS relative to the transducer size) and operator inexperience are not uncommon, no standard guidelines for ideal probe placement are currently available. Herein, we conducted a prospective observational study to identify an ideal measurement site and respiratory condition for TE by characterizing anatomical and biomechanical properties of the ICSs using ultrasound B-mode and elasticity imaging.

METHODS

Intercostal ultrasound was performed pointwise at four specific sites in 59 patients to simultaneously measure the width, stiffness, and skin‒liver capsule distance (SCD) of the ICSs over the liver, under end-inspiratory and end-expiratory conditions. Intersections between the 8th ICS and anterior axillary line, the 7th ICS and anterior axillary line, the 8th ICS and mid-axillary line, and the 7th ICS and mid-axillary line were defined as Sites 1 to 4, respectively.

RESULTS

Results indicated that Sites 2 and 3 presented greater intercostal width; Sites 3 and 4 displayed lower intercostal stiffness; Sites 2 and 3 exhibited a shorter SCD. The ICSs were significantly wider and stiffer at end-inspiration. Additionally, the liver was more easily visualized at Sites 1 and 3.

CONCLUSION

We recommend Site 3 for TE probe placement owing to its greater width, lower stiffness, and smaller abdominal wall thickness. Performing TE at end-inspiration is preferred to minimize transducer-rib interferences. This study paves the way toward a standardized TE examination procedure.

CRITICAL RELEVANCE STATEMENT

A standardized measurement protocol for WHO-recommended liver TE was first established to improve the success and efficiency of the examination procedure.

KEY POINTS

WHO-recommended TE is unreliable or fails due to intercostal space-related factors. The 8th intercostal space on the mid-axillary line and end-inspiration are recommended. This standardized protocol aids in handling challenging cases and simplifies operational procedures.

Fatty liver is associated with significant liver inflammation and increases the burden of advanced fibrosis in chronic HBV infection

BACKGROUND

Concurrent non-alcoholic fatty liver disease (NAFLD) is common in patients with chronic HBV infection. But the impact of fatty liver on the histologic progression of HBV infection remains controversial.

METHODS

Consecutive HBV-infected patients who underwent liver biopsy between 2016 and 2021 were included. Alcohol consumption and other types of viral hepatitis were excluded. All biopsies were scored for grading and staging by Scheuer's score, and the steatosis was scored as an estimate of the percentage of liver parenchyma replaced by fat. Logistic regression analyses were applied to assess the associated factors for significant liver inflammation (G ≥ 2), significant fibrosis (S ≥ 2) and advanced fibrosis (S ≥ 3).

RESULTS

Among the 871 HBV-infected patients, hepatic steatosis was prevalent in 255 patients (29.28%). Significant liver inflammation was present in 461 patients (52.93%). Significant fibrosis was observed in 527 patients (60.51%), while advanced liver fibrosis was observed in 171 patients (19.63%). Patients with concomitant NAFLD were more likely to have significant liver inflammation and advanced fibrosis. Fatty liver was an independent risk factor for significant liver inflammation (OR: 2.117, 95% CI: 1.500-2.988), but it could not predict the development of fibrosis. Especially, in HBV-infected patients with persistent normal ALT (immune tolerant and inactive carrier phase), the presence of significant liver inflammation was higher in NAFLD than those without NAFLD. The prevalence of advanced liver fibrosis was higher in NAFLD than non-NAFLD only in the immune tolerant phase, while NAFLD did not increase fibrosis burden in other stages of HBV infection. We developed a predictive model for significant liver inflammation with the area under receiver operating characteristic curve (AUROC) of 0.825, and a model for significant fibrosis with the AUROC of 0.760.

CONCLUSIONS

NAFLD is independently associated with significant liver inflammation, and increases the burden of advanced liver fibrosis in HBV-infected patients. The influence of NAFLD on the degree of liver inflammation and fibrosis is different in distinct clinical phases of chronic HBV infection.

Transient Elastography as the First-Line Assessment of Liver Fibrosis and Its Correlation with Serum Markers

Background and objectives: Recently, rapid progress has been made in the development of noninvasive methods for liver fibrosis assessment. The study aimed to assess the correlation between LSM and serum fibrosis markers to identify patients with advanced liver fibrosis in daily clinical practice. Methods: Between 2017 and 2019, 89 patients with chronic liver disease of various etiology, 58 males and 31 females, were enrolled in the study and underwent ultrasound examination, vibration-controlled transient elastography (VCTE), AST to Platelet Ratio Index (APRI score), Fibrosis-4 (FIB-4) score, and enhanced liver fibrosis (ELF) test. Results: The diagnoses were as follows: NAFLD (30.3%), HCV (24.3%), HBV (13.1%), ALD (10.1%), other (7.8%). Their median age was 49 (21-79), and their median BMI was 27.5 (18.4-39.5). The median liver stiffness measurement (LSM) was 6.7 kPa (2.9-54.2 kPa), the median of the ELF test was 9.0 (7.3-12.6), and the median APRI was 0.40 (0.13-3.13). Advanced fibrosis assessed by LSM was present in 18/89 (20.2%) patients. The LSM values correlated with the ELF test results (r² = 0.31, p < 0.0001), with the APRI score (r² = 0.23, p < 0.0001), the age of the patients (r² = 0.14, p < 0.001), and with the FIB-4 values (r² = 0.58, p < 0.0001). The ELF test values correlated with the APRI score (r² = 0.14, p = 0.001), the age (r² = 0.38, p < 0.0001), and the FIB-4 (r² = 0.34, p < 0.0001). By determining the confidence intervals of the linear model, we proved that patients younger than 38.1 years have a 95% probability of absence of advanced liver fibrosis when assessed by VCTE. Conclusions: We identified APRI and FIB-4 as simple tools for screening liver disease in primary care in an unselected population of patients. The results also showed that individuals younger than 38.1 years had a negligible risk of advanced liver fibrosis.

How to Identify Advanced Fibrosis in Adult Patients with Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH) Using Ultrasound Elastography-A Review of the Literature and Proposed Multistep Approach

Non-alcoholic fatty liver disease (NAFLD), and its progressive form, non-alcoholic steatohepatitis (NASH), represent, nowadays, real challenges for the healthcare system. Liver fibrosis is the most important prognostic factor for NAFLD, and advanced fibrosis is associated with higher liver-related mortality rates. Therefore, the key issues in NAFLD are the differentiation of NASH from simple steatosis and identification of advanced hepatic fibrosis. We critically reviewed the ultrasound (US) elastography techniques for the quantitative characterization of fibrosis, steatosis, and inflammation in NAFLD and NASH, with a specific focus on how to differentiate advanced fibrosis in adult patients. Vibration-controlled transient elastography (VCTE) is still the most utilized and validated elastography method for liver fibrosis assessment. The recently developed point shear wave elastography (pSWE) and two-dimensional shear wave elastography (2D-SWE) techniques that use multiparametric approaches could bring essential improvements to diagnosis and risk stratification.

Performance of Noninvasive Tests of Fibrosis Among Asians, Hispanic, and non-Hispanic Whites in the STELLAR Trials

BACKGROUND & AIMS

The effect of race on routinely available noninvasive tests of fibrosis is incompletely understood. This study evaluated the performance of noninvasive tests among white and Asian patients in the STELLAR trials (NCT03053050 and NCT03053063), which evaluated selonsertib in patients with advanced (F3-F4) fibrosis due to nonalcoholic steatohepatitis (NASH).

METHODS

Baseline liver biopsies were centrally read using the NASH Clinical Research Network system, and 4 noninvasive tests (Nonalcoholic fatty liver disease fibrosis score [NFS], Fibrosis-4 index [FIB-4], Enhanced Liver Fibrosis test [ELF], and liver stiffness by vibration-controlled transient elastography) were measured. The performance of these tests to discriminate advanced fibrosis was evaluated using areas under the receiver operating characteristics curves with 5-fold cross-validation repeated 100 times.

RESULTS

Among 3207 patients screened with evaluable liver histology, 2281 were whites and 762 were Asians. Seventy-two percent of whites and 67% of Asians had advanced fibrosis. The areas under the receiver operating characteristics curves of the noninvasive tests for advanced fibrosis were similar in whites and Asians: 0.73 and 0.75 for NFS, 0.78 and 0.80 for FIB-4, 0.79 and 0.81 for ELF, and 0.80 and 0.83 for liver stiffness, respectively. At the published cutoffs, the tests had similar sensitivities and specificities in the 2 groups. However, the sensitivities of NFS, FIB-4, and ELF were low in both white and Asian patients younger than 40 years.

CONCLUSIONS

In the global phase III STELLAR trials, the diagnostic performance of routinely available noninvasive tests for the detection of advanced fibrosis due to NASH was acceptable and similar between white and Asian patients.

Validation and Performance of FibroScan®-AST (FAST) Score on a Brazilian Population with Nonalcoholic Fatty Liver Disease

BACKGROUND AND AIM

FAST score has a good performance for diagnosing the composite of NASH + NAS ≥ 4 + F ≥ 2. However, it has not been evaluated in Latin American individuals with nonalcoholic fatty liver disease (NAFLD). We aimed to analyze the performance of the FAST score in a Brazilian NAFLD population.

METHODS

Cross-sectional study was held in ≥ 18 years NAFLD patients diagnosed by ultrasonography and submitted to liver biopsy (LB). Liver stiffness (LSM) and CAP measurements were performed with FibroScan®, using M (BMI < 32 kg/m²) or XL probes. Area under receiver operating characteristic (AUROC) curves were calculated as well as sensitivity (S), specificity (Spe), positive predictive value (VPP) and negative predictive value (NPV) for the previously established FAST score cut-offs.

RESULTS

Among 287 patients included (75% female; mean age 55 ± 10 years), NASH + NAS ≥ 4 + F ≥ 2 was reported in 30% of LB. For the FAST cut-off of 0.35, the S and NPV to rule out NASH + NAS ≥ 4 + F ≥ 2 were 78.8% and 87.8%, respectively. Regarding the cut-off of 0.67, the Spe and PPV to rule-in NASH + NAS ≥ 4 + F ≥ 2 were 89.1%, 61.8%, respectively. The AUROC of FAST for all included patients was 0.78 (95% CI 0.72-0.84) and for those with ≥ 32 kg/m² was 0.81 (95% CI 0.74-0.88).

CONCLUSION

FAST score has a good performance in a Brazilian NAFLD population, even in patients with higher BMI when the XL probe is adopted. Therefore, FAST can be used as a noninvasive screening tool mainly for excluding the diagnosis of progressive NASH, reducing the number of unnecessary liver biopsies.

Diagnostic Performance of 2-D Shear Wave Elastography on the Evaluation of Hepatic Fibrosis with Emphasis on Impact of the Different Region-of-Interest Methods

The purpose of this study was to evaluate the impact of the different region-of-interest (ROI) methods of 2-D shear wave elastography (2-D SWE) on hepatic fibrosis diagnosis. In this retrospective study, 83 patients who underwent 2-D SWE with three ROI methods (a circle ROI, a box ROI and multiple ROIs in an elastogram) and transient elastography (TE) were included. Liver stiffness (LS) was measured five times with each ROI method. These LS values were compared, and their correlation with those obtained from TE was evaluated. The LS values obtained using the three different ROI methods differed statistically (p < 0.001). However, the LS values obtained using each ROI method of 2-D SWE were highly correlated with those obtained using TE (r > 0.7, p < 0.001). All three ROI methods of 2-D SWE had high areas under the receiver operating characteristic curve in diagnosing significant fibrosis and cirrhosis (0.841, 0.820 and 0.840, respectively; 0.962, 0.946 and 0.945, respectively). There were no significant differences in area under the receiver operating characteristic curve among the ROI methods of 2-D SWE. Regardless of the ROI method, 2-D SWE had high performance in diagnosing hepatic fibrosis.

Non-alcoholic steatohepatitis in liver transplant recipients diagnosed by serum cytokeratin 18 and transient elastography: A prospective study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) seem common after liver transplantation.

AIM

To investigate incidence and predictors of NAFLD and NASH by employing noninvasive testing in liver transplant recipients, namely controlled attenuation parameter (CAP) and the serum biomarker cytokeratin 18 (CK-18). We also evaluated the diagnostic accuracy of CK-18 and CAP compared to liver histology.

METHODS

We prospectively recruited consecutive adult patients who received liver transplant at the McGill University Health Centre between 2015-2018. Serial measurements of CK-18 and CAP were recorded. NAFLD and NASH were diagnosed by CAP ≥ 270 dB/m, and a combination of CAP ≥ 270 dB/m with CK-18 > 130.5 U/L, respectively. Incidences and predictors of NAFLD and NASH were investigated using survival analysis and Cox proportional hazards.

RESULTS

Overall, 40 liver transplant recipients (mean age 57 years; 70% males) were included. During a median follow-up of 16.8 mo (interquartile range 15.6-18.0), 63.0% and 48.5% of patients developed NAFLD and NASH, respectively. On multivariable analysis, after adjusting for sex and alanine aminotransferase, body mass index was an independent predictor of development of NAFLD [adjusted hazard ratio (aHR): 1.21, 95% confidence interval (CI): 1.04-1.41; P = 0.01] and NASH (aHR: 1.26, 95%CI: 1.06-1.49; P < 0.01). Compared to liver histology, CAP had a 76% accuracy to diagnose NAFLD, while the accuracy of CAP plus CK-18 to diagnose NASH was 82%.

CONCLUSION

NAFLD and NASH diagnosed non-invasively are frequent in liver transplant recipients within the first 18 mo. Close follow-up and nutritional counselling should be planned in overweight patients.

An ultrasound image-based deep multi-scale texture network for liver fibrosis grading in patients with chronic HBV infection

BACKGROUND & AIMS

The evaluation of the stage of liver fibrosis is essential in patients with chronic liver disease. However, due to the low quality of ultrasound images, the non-invasive diagnosis of liver fibrosis based on ultrasound images is still an outstanding question. This study aimed to investigate the diagnostic accuracy of a deep learning-based method in ultrasound images for liver fibrosis staging in multicentre patients.

METHODS

In this study, we proposed a novel deep learning-based approach, named multi-scale texture network (MSTNet), to assess liver fibrosis, which extracted multi-scale texture features from constructed image pyramid patches. Its diagnostic accuracy was investigated by comparing it with APRI, FIB-4, Forns and sonographers. Data of 508 patients who underwent liver biopsy were included from 4 hospitals. The area-under-the ROC curve (AUC) was determined by receiver operating characteristics (ROC) curves for significant fibrosis (≥F2) and cirrhosis (F4).

RESULTS

The AUCs (95% confidence interval) of MSTNet were 0.92 (0.87-0.96) for ≥F2 and 0.89 (0.83-0.95) for F4 on the validation group, which significantly outperformed APRI, FIB-4 and Forns. The sensitivity and specificity of MSTNet (85.1% (74.5%-92.0%) and 87.6% (78.0%-93.6%)) were better than those of three sonographers in assessing ≥F2.

CONCLUSIONS

The proposed MSTNet is a promising ultrasound image-based method for the non-invasive grading of liver fibrosis in patients with chronic HBV infection.

Non-invasive diagnosis of nonalcoholic fatty liver disease in patients with type 2 diabetes

Liver disease has emerged as a significant cause of death in people with type 2 diabetes (T2D). Due to a common underlying pathogenic mechanism, namely insulin resistance, T2D represents the main risk factor for nonalcoholic fatty liver disease (NAFLD), characterized by a buildup of fat in the liver. Globally, NAFLD is the most common liver disease, affecting a quarter of the general adult population. The development of nonalcoholic steatohepatitis (NASH) signifies an increased risk of liver fibrosis progression that can result in cirrhosis, hepatocellular carcinoma (HCC), and death. Liver fibrosis progression and development of cirrhosis is mostly asymptomatic until complications from decompensated end-stage liver disease arise. Traditionally, liver biopsy is used to diagnose NASH and stage fibrosis, however, it is invasive and costly. Non-invasive diagnostic alternatives include serum biomarkers and imaging techniques. Early identification of advanced liver fibrosis is pivotal to prompt initiation of targeted surveillance, including screening for HCC, as well as providing options for current and investigational therapeutic interventions to reduce fibrosis progression. This review gives an update on non-invasive diagnostic tools for NAFLD and liver fibrosis in the specific context of T2D, providing clinicians a pragmatic diagnostic approach to this frequent comorbidity in diabetes medicine.

Performance of liver stiffness measurements obtained with FibroScan is affected by glucose metabolism in patients with nonalcoholic fatty liver disease

Background

The performance of liver stiffness measurements (LSMs) obtained using FibroScan can be affected by several factors, and cut-off values are different for fibrosis caused by various aetiologies. The study aims to evaluate the diagnostic accuracy of LSM in nonalcoholic fatty liver disease (NAFLD) patients with abnormal glucose metabolism and investigate whether the LSM value would be affected by metabolic indicators.

Methods

The study involved 91 NAFLD patients with abnormal glucose metabolism who underwent liver biopsy. The diagnostic accuracy of LSM value was evaluated by the receiver operator characteristic (ROC) curves, with the biopsy results taken as the gold standard. Multivariate linear regression and subgroup analysis were performed to determine the correlated indicators.

Results

The areas under the ROC curves (AUROCs) of LSM values for detecting fibrosis stage ≥1, 2, 3 and 4 were 0.793 (95% confidence interval [CI]: 0.695–0.871), 0.764 (95% CI: 0.663–0.846), 0.837 (95% CI: 0.744–0.906) and 0.902 (95% CI: 0.822–0.955), with cut-off values of 6.3, 7.6, 8.3 and 13.8 kPa, respectively. Multivariate linear regression demonstrated that haemoglobin A1c (HbA1c, β = 0.205, P = 0.026) and alanine aminotransferase (ALT, β = 0.192, P = 0.047) were independently associated with the LSM value after adjustment for fibrosis stage, ballooning and inflammation grade from liver biopsy. Subgroup analysis demonstrated that LSM values were slightly higher in patients with HbA1c ≥7% than in those with HbA1c < 7% and in patients with body mass index (BMI) ≥30 kg/m² than in those with BMI < 30 kg/m².

Conclusions

FibroScan was valuable for the evaluation of liver fibrosis in NAFLD patients with abnormal glucose metabolism. FibroScan is recommended to evaluate severe fibrosis, especially to exclude advanced fibrosis. Glucose metabolism state may affect LSM values.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01453-5.

Hepatocellular Carcinoma and Non-Alcoholic Fatty Liver Disease: A Step Forward for Better Evaluation Using Ultrasound Elastography

Simple Summary

Non-alcoholic fatty liver disease (NAFLD) attracts a lot of attention, due to the increasing prevalence and progression to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Consequently, new non-invasive, cost-effective diagnostic methods are needed. This review aims to explore the diagnostic performance of ultrasound (US) elastography in NAFLD and NAFLD-related HCC, adding a new dimension to the conventional US examination—the liver stiffness quantification. The vibration controlled transient elastography (VCTE), and 2D-Shear wave elastography (2D-SWE) are effective in staging liver fibrosis in NAFLD. VCTE presents the upside of assessing steatosis through the controlled attenuation parameter. Hereby, we critically reviewed the elastography techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography and 2D-SWE. 2D-SWE presents a great potential to differentiate malignant from benign FLLs, guiding the clinician towards the next diagnostic steps. As a disease-specific surveillance tool, US elastography presents prognostic capability, improving the NAFLD-related HCC monitoring.

Abstract

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in the general population prompts for a quick response from physicians. As NAFLD can progress to liver fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC), new non-invasive, rapid, cost-effective diagnostic methods are needed. In this review, we explore the diagnostic performance of ultrasound elastography for non-invasive assessment of NAFLD and NAFLD-related HCC. Elastography provides a new dimension to the conventional ultrasound examination, by adding the liver stiffness quantification in the diagnostic algorithm. Whilst the most efficient elastographic techniques in staging liver fibrosis in NAFLD are vibration controlled transient elastography (VCTE) and 2D-Shear wave elastography (2D-SWE), VCTE presents the upside of assessing steatosis through the controlled attenuation parameter (CAP). Hereby, we have also critically reviewed the most important elastographic techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography (pSWE) and 2D-SWE. As our paper shows, elastography should not be considered as a substitute for FLL biopsy because of the stiffness values overlap. Furthermore, by using non-invasive, disease-specific surveillance tools, such as US elastography, a subset of the non-cirrhotic NAFLD patients at risk for developing HCC can be detected early, leading to a better outcome. A recent ultrasomics study exemplified the wide potential of 2D-SWE to differentiate benign FLLs from malignant ones, guiding the clinician towards the next steps of diagnosis and contributing to better long-term disease surveillance.

The Use of Transient Elastography Technology in the Bariatric Patient: a Review of the Literature

Transient elastography (TE) is a non-invasive technology that demonstrates promise in assessing liver steatosis and fibrosis without the risks of traditional percutaneous liver biopsy. Many studies have examined its reliability in respect to liver biopsy, but fewer have examined using TE in obese and bariatric surgery patients. With evidence showing that bariatric surgery can lead to improvement of liver steatosis and fibrosis, TE has the potential to provide a simple avenue of hepatic assessment in patients before and after procedures. This review article investigates what is known about the reliability of TE and its implementation in obese and bariatric surgery patients.

Multicenter prospective study to validate a new transient elastography device for staging liver fibrosis in patients with chronic hepatitis B

OBJECTIVES

To validate the operational and diagnostic performances of a new device for transient elastography (TE), FibroTouch, for liver fibrosis in patients with chronic hepatitis B (CHB).

METHODS

In this prospective multicenter study, adult patients with CHB and valid liver pathological results were recruited to validate the operational and diagnostic performance of a TE device by FibroTouch for staging liver fibrosis.

RESULTS

In total, 517 patients with histologically proven CHB were enrolled. All had achieved at least 10 successful liver stiffness measurements (LSM), resulting in a success rate of 99.1% and reliable evaluations of 95.2%. Altogether 412 patients were included to analyze the diagnostic performance of FibroTouch. The area under the receiver operating characteristic curve for the LSM was 0.846 (95% confidence interval [CI] 0.808-0.880) for fibrosis stage ≥ F1, 0.850 (95% CI 0.811-0.883) for ≥ F2, 0.908 (95% CI 0.876-0.934) for ≥ F3 and 0.874 (95% CI 0.836-0.903) for F4. The diagnostic accuracy of LSM was superior to that of gamma-glutamyl transpeptidase-to-platelet ratio (GPR), aminotransferase-to-platelet ratio index (APRI), or fibrosis index based on 4 factors (FIB-4) index in staging fibrosis F2-F4 (P = 0.007 to < 0.0001). Optimal LSM cut-off values for diagnosing fibrosis stage ≥ F1, ≥ F2, ≥ F3, and F4 were 5.5 kPa, 7.85 kPa, 10.0 kPa, and 12.7 kPa, respectively.

CONCLUSION

FibroTouch has a high success rate and good reliability in staging liver fibrosis in patients with CHB.

Advances in ultrasound elastography for nonalcoholic fatty liver disease

The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) has increased rapidly worldwide, making NAFLD/NASH an important global health problem from both a medical and socioeconomic standpoint. NAFLD is also regarded as a liver component of metabolic syndrome and is reported to be associated with the risk factors for metabolic syndrome. It has been suggested that NAFLD/NASH be recognized both as a liver-specific disease and as an early mediator of systemic diseases. Liver biopsy is recommended as the gold standard method for the diagnosis of NASH and for the staging of liver fibrosis in patients with NAFLD. However, because of its high cost, high risk, and high weightage as a healthcare resource, invasive liver biopsy is a poorly suited diagnostic test for such a highly prevalent condition. Therefore, the development of reliable noninvasive methods for the assessment of liver fibrosis has been sought to estimate the risk of progression of NASH to cirrhosis, estimate the risk of cardiovascular events, aid in the surveillance for HCC, and guide therapy in patients with NAFLD/NASH. In this review, we highlight the principles and recent advances in ultrasound elastography techniques (Real-time Tissue Elastography^®, vibration-controlled transient elastography, point shear wave elastography, and two-dimensional shear wave elastography) used to evaluate the liver fibrosis stage and steatosis grade in patients with NAFLD.

Elastography Techniques for the Assessment of Liver Fibrosis in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is expected to increase in prevalence because of the ongoing epidemics of obesity and diabetes, and it has become a major cause of chronic liver disease worldwide. Liver fibrosis is associated with long-term outcomes in patients with NAFLD. Liver biopsy is recommended as the gold standard method for the staging of liver fibrosis. However, it has several problems. Therefore, simple and noninvasive methods for the diagnosis and staging of liver fibrosis are urgently needed in place of biopsy. This review discusses recent studies of elastography techniques (vibration-controlled transient elastography, point shear wave elastography, two-dimensional shear wave elastography, and magnetic resonance elastography) that can be used for the assessment of liver fibrosis in patients with NAFLD.

Noninvasive Serum Fibrosis Markers are Associated with Coronary Artery Calcification in Patients with Nonalcoholic Fatty Liver Disease

Background/Aims

Advanced hepatic fibrosis is associated with cardiovascular disease (CVD) in patients with nonalcoholic fatty liver disease (NAFLD). We investigated the association between noninvasive serum fibrosis markers and the coronary artery calcium score (CACS) in subjects with NAFLD.

Methods

We analyzed 665 NAFLD subjects without chronic liver disease or heart disease between 2011 and 2015. The noninvasive fibrosis markers that were used to evaluate the severity of hepatic fibrosis included the NAFLD fibrosis score (NFS), fibrosis-4 (FIB-4) score, Forn's index, and the aspartate aminotransferase to platelet ratio index (APRI).

Results

The areas under the receiver operating characteristics curves for the NFS, FIB-4 score, Forn's index and APRI for predicting CACS >100 were 0.689, 0.683, 0.659, and 0.595, respectively. According to the multivariate analysis, older age, increased body mass index (BMI), and decreased estimated glomerular filtration rate (eGFR) were significant factors associated with CACS >100. The NFS, FIB-4 score and APRI were significantly associated with CACS >100 after adjusting for age and gender (p=0.006, p=0.012, and p=0.012, respectively) and after adjusting for age, gender, BMI and eGFR (p=0.013, p=0.022, and p=0.027, respectively). Scores integrating noninvasive fibrosis markers and other risk factors improved the predictive accuracy.

Conclusions

The NFS and FIB-4 score were associated with coronary atherosclerosis in subjects with NAFLD. Furthermore, scores integrating these noninvasive scores and risk factors for CVD showed good discriminatory power in predicting CACS >100. Therefore, noninvasive serum fibrosis markers may be useful tools for identifying NAFLD subjects at a high risk for CVD.

Prospective comparison of transient elastography, point shear wave elastography, APRI and FIB-4 for staging liver fibrosis in chronic viral hepatitis

Ultrasound-based elastography and serum indexes have been individually validated as noninvasive methods for staging liver fibrosis in chronic viral hepatitis. We aimed to compare the accuracy of transient elastography (TE), shear wave elastography (SWE), aspartate aminotransferase to platelet index (APRI) and Fibrosis-4 index (FIB-4) with the METAVIR liver fibrosis staging in viral hepatitis patients. We enrolled 121 treatment-naïve chronic hepatitis B and C monoinfected patients. All underwent liver biopsy had biochemistry tests and liver stiffness measurements by TE using M and XL probes followed by point SWE performed on the same day. The accuracy of each method for predicting different fibrosis stages was demonstrated as an area under the receiver operating characteristic (AUROC) curves. The AUROCs of TE using M and XL probes, SWE, APRI and FIB-4 were 0.771, 0.761, 0.700, 0.698 and 0.697, respectively, for significant fibrosis; 0.974, 0.973, 0.929, 0.738 and 0.859, respectively, for advanced fibrosis; and 0.954, 0.949, 0.962, 0.765 and 0.962, respectively, for cirrhosis. TE using the M probe was comparable to the XL probe in detecting all fibrosis stages. TE was superior to SWE for assessing significant fibrosis and advanced fibrosis. For cirrhosis, the performances of TE, SWE and FIB-4 were similar. APRI was least accurate in liver fibrosis staging. To conclude, for patients with viral hepatitis, TE using either M or XL probe is an effective noninvasive test for assessing liver fibrosis, particularly advanced fibrosis and cirrhosis, while SWE and FIB-4 possess an excellent accuracy in predicting cirrhosis.

Non-Alcoholic Fatty Liver Disease in Patients with Type 2 Diabetes: Evaluation of Hepatic Fibrosis and Steatosis Using Fibroscan

Patients with type 2 diabetes mellitus (T2DM) are at increased risk of non-alcoholic fatty liver disease (NAFLD) and might eventually progress to advanced fibrosis, cirrhosis and hepatocellular carcinoma (HCC). Recommendations on whether to screen for NAFLD in diabetic patients remains conflicted between major guidelines. Transient elastography using FibroScan with CAP (controlled attenuation parameter) can assess both liver steatosis and fibrosis simultaneously. This paper took a new look at the prevalence of NAFLD and the severity of fibrosis among T2DM patients in Vietnam. The study was conducted using a cross-sectional design in T2DM adults who attended Dai Phuoc Ho Chi Minh Polyclinic and Polyclinic of Pham Ngoc Thach University of Medicine. Liver steatosis and fibrosis was assessed by FibroScan. NAFLD was diagnosed if CAP > 233 dB/m (steatosis > 5%). Data were analyzed using STATA 12 software program. We found that a total of 307 type 2 diabetic patients qualified for the study's criteria. The prevalence of NAFLD in T2DM patients based on FibroScan was 73.3%. Rates of mild, moderate and severe steatosis were 20.5%, 21.8% and 30.9%, respectively. The prevalence of significant fibrosis (≥ F2), advanced fibrosis (≥ F3) and cirrhosis (F4) was 13.0%, 5.9% and 3.6%, respectively. On multivariate analysis, aspartate aminotransferase (AST) (OR: 1.067; 95% CI: 1.017-1.119; p = 0.008) and platelet levels (OR: 0.985; 95% CI: 0.972-0.999; p = 0.034) were independent of risk factors of advanced fibrosis. Thus, our study supports screening for NAFLD and for evaluating the severity of liver fibrosis in T2DM patients.

Hepatitis B Virus: Advances in Prevention, Diagnosis, and Therapy

Currently, despite the use of a preventive vaccine for several decades as well as the use of effective and well-tolerated viral suppressive medications since 1998, approximately 250 million people remain infected with the virus that causes hepatitis B worldwide. Hepatitis C virus (HCV) and hepatitis B virus (HBV) are the leading causes of liver cancer and overall mortality globally, surpassing malaria and tuberculosis. Linkage to care is estimated to be very poor both in developing countries and in high-income countries, such as the United States, countries in Western Europe, and Japan. In the United States, by CDC estimates, only one-third of HBV-infected patients or less are aware of their infection. Some reasons for these low rates of surveillance, diagnosis, and treatment include the asymptomatic nature of chronic hepatitis B until the very late stages, a lack of curative therapy with a finite treatment duration, a complex natural history, and a lack of knowledge about the disease by both care providers and patients. In the last 5 years, more attention has been focused on the important topics of HBV screening, diagnosis of HBV infection, and appropriate linkage to care. There have also been rapid clinical developments toward a functional cure of HBV infection, with novel compounds currently being in various phases of progress. Despite this knowledge, many of the professional organizations provide guidelines focused only on specific questions related to the treatment of HBV infection. This focus leaves a gap for care providers on the other HBV-related issues, which include HBV's epidemiological profile, its natural history, how it interacts with other viral hepatitis diseases, treatments, and the areas that still need to be addressed in order to achieve HBV elimination by 2030. Thus, to fill these gaps and provide a more comprehensive and relevant document to regions worldwide, we have taken a global approach by using the findings of global experts on HBV as well as citing major guidelines and their various approaches to addressing HBV and its disease burden.

The performance of M and XL probes of FibroScan for the diagnosis of steatosis and fibrosis on a Brazilian nonalcoholic fatty liver disease cohort

OBJECTIVES

Recently, controlled attenuation parameter (CAP) was incorporated for XL probe. However, its performance through M and XL probes has been scarcely evaluated in nonalcoholic fatty liver disease (NAFLD). The performance of probes regarding transient elastography by Fibroscan is still under debate.

AIM

Compare the performance of CAP and transient elastography in NAFLD patients obtained through XL with M probes using histological analysis as gold standard.

METHODS

NAFLD patients underwent liver biopsy and FibroScan/CAP with M and XL probes the same day. C-statistic evaluated CAP performance in the identification of moderate/severe (≥33%) and severe (≥66%) steatosis by both probes and transient elastography performance for identification of significant fibrosis (≥F2).

RESULTS

Eighty-one patients (74% female; age 54.2 ± 9.9 years; BMI 32.8 ± 5.2/ BMI ≥ 25 92.6%; 96% metabolic syndrome; 60% diabetes mellitus) were included. Mean CAP with M and XL probes was 314 ± 39 and 325 ± 47 dB/m, respectively. The areas under receiver operating characteristic curves (AUROCs) of the M and XL probes for steatosis detection ≥33% were 0.75 (0.64-0.84) and 0.76 (0.65-0.84) (P = 0.95) and for steatosis ≥66% 0.83 (0.73-0.90) and 0.82 (0.71-0.89) (P = 0.73), respectively, with similar performances for both degrees of steatosis. Regarding transient elastography, AUROCs of M and XL probes for ≥F2 were 0.82 (0.71-0.93) and 0.80 (0.69-0.92) (P = 0.66).

CONCLUSION

Performance of M and XL probes is similar for the diagnosis of moderate and severe steatosis and significant fibrosis even on a overweight population with NAFLD.

Limitations of non-invasive tests for assessment of liver fibrosis

The diagnostic assessment of liver injury is an important step in the management of patients with chronic liver disease (CLD). Although liver biopsy is the reference standard for the assessment of necroinflammation and fibrosis, the inherent limitations of an invasive procedure, and need for repeat sampling, have led to the development of several non-invasive tests (NITs) as alternatives to liver biopsy. Such non-invasive approaches mostly include biological (serum biomarker algorithms) or physical (imaging assessment of tissue stiffness) assessments. However, currently available NITs have several limitations, such as variability, inadequate accuracy and risk factors for error, while the development of a newer generation of biomarkers for fibrosis may be limited by the sampling error inherent to the reference standard. Many of the current NITs were initially developed to diagnose significant fibrosis in chronic hepatitis C, subsequently refined for the diagnosis of advanced fibrosis in patients with non-alcoholic fatty liver disease, and further adapted for prognostication in CLD. An important consideration is that despite their increased use in clinical practice, these NITs were not designed to reflect the dynamic process of fibrogenesis, differentiate between adjacent disease stages, diagnose non-alcoholic steatohepatitis, or follow longitudinal changes in fibrosis or disease activity caused by natural history or therapeutic intervention. Understanding the strengths and limitations of these NITs will allow for more judicious interpretation in the clinical context, where NITs should be viewed as complementary to, rather than as a replacement for, liver biopsy.

Unresolved issues of immune tolerance in chronic hepatitis B

During the natural course of chronic hepatitis B virus infection, immune-tolerant phase is characterized by high viral replication, the presence of HBV e antigen (HBeAg), and normal or minimally elevated serum alanine aminotransferase. Immune-tolerant phase is usually regarded as a benign course of the disease. International guidelines recommend observation rather than treatment during immune-tolerant phase. In this article, we review unresolved issues related to the definition of true immune-tolerant phase and the benefit of antiviral treatment. Defining true immune-tolerant phase requires a careful approach and long-term follow-up. In previous studies, many patients were misclassified as being immune-tolerant phase. Noninvasive methods of assessing fibrosis are warranted for patients in the immune-tolerant phase. Yet, there has been controversy over the benefit and harm of antiviral treatment for immune-tolerant phase patients. Thus, further larger scale studies are needed to investigate the prognosis of patients in true immune-tolerant phase and their need for antiviral therapy.

Confounding factors of non-invasive tests for nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) affects at least 25% of the general adult population worldwide. Because only a fraction of the patients would develop liver-related complications, it is preferable to perform non-invasive tests as the initial assessment. This review summarizes the known and potential confounding factors that affect the performance of non-invasive tests of hepatic steatosis and fibrosis in patients with NAFLD. Clinicians may apply the knowledge and exercise caution in selecting investigations and interpreting test results when confounding factors are present.

Noninvasive liver fibrosis assessment in chronic viral hepatitis C: agreement among 1D transient elastography, 2D shear wave elastography, and magnetic resonance elastography

PURPOSE

To assess the agreement of one-dimensional transient elastography (1D-TE), two-dimensional shear wave elastography (2D-SWE), and magnetic resonance elastography (MRE) in a consecutive cohort of patients affected by hepatitis C virus (HCV) and to understand which patient-related factors are associated with disagreement.

METHODS

Ninety-one consecutive patients with current or previous chronic HCV infection were enrolled between March 2017 and September 2018. We assessed the correlation between stiffness measurements expressed in kilopascals (kPa). After converting kPa values in three groups of increasing fibrosis burden using validated cut-off values, we assessed the agreement among the different techniques. Factors influencing inter-modality disagreement were examined by employing multivariate logistic regression analysis.

RESULTS

Seventy-seven patients met the inclusion criteria and had reliable measurements by all stiffness imaging techniques. At the quantitative analysis, a strong correlation between stiffness measurements was found (Spearman's rho values ranging from 0.7 to 0.89 in all pairs of techniques). Complete concordance among MRE, 1D-TE, and 2D-SWE was found in 64.9% of patients, and the agreement was highest between MRE and 1D-TE, with κ value of 0.801. In only 2/77 patients (2.6%), there was complete disagreement. High body mass index (BMI) was the only factor significantly associated with inter-modality discordance.

CONCLUSIONS

MRE, 1D-TE, and 2D-SWE assigned the majority of patients to the same fibrosis group. The agreement was at least good, and there was a strong correlation between kPa values in all three pairs of techniques. Highest agreement was found between MRE and 1D-TE. High BMI was associated with discordance among the techniques.

Application of transient elastography in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Although it has become one of the leading causes of cirrhosis and hepatocellular carcinoma in the Western world, the proportion of NAFLD patients developing these complications is rather small. Therefore, current guidelines recommend non-invasive tests for the initial assessment of NAFLD. Among the available non-invasive tests, transient elastography by FibroScan^® (Echosens, Paris, France) is commonly used by hepatologists in Europe and Asia, and the machine has been introduced to the United States in 2013 with rapid adoption. Transient elastography measures liver stiffness and the controlled attenuation parameter simultaneously and can serve as a one-stop examination for both liver steatosis and fibrosis. Liver stiffness measurement also correlates with clinical outcomes and can be used to select patients for varices screening. Although obesity is a common reason for measurement failures, the development of the XL probe allows successful measurements in the majority of obese patients. This article reviews the performance and limitations of transient elastography in NAFLD and highlights its clinical applications. We also discuss the reliability criteria for transient elastography examination and factors associated with false-positive liver stiffness measurements.

Non-Alcoholic Fatty Liver Disease in Non-Obese Individuals: Prevalence, Pathogenesis and Treatment

Non-alcoholic fatty liver disease (NAFLD) parallels comorbidities such as metabolic syndrome, dyslipidaemia or diabetes. Although NAFLD is very prevalent in overweight-obese individuals (i.e. body mass index ≥25 kg/m2), recent studies point to the presence of NAFLD in non-obese individuals, for both the Asian (<25 kg/m2) and Caucasian (<30 kg/m2) populations. This paper discusses the pathogenic pathways and current treatment options of NAFLD in non-obese populations. In this respect, non-obese subjects also need to undergo the medical screening for NAFLD. Across the scientific community, we aim to promote the advancement of knowledge in this emerging field.

A review of the use of transient elastography in the assessment of fibrosis and steatosis in the post-liver transplant patient

Liver biopsy is considered the gold standard method for diagnosing and staging liver disease, particularly in the post-liver transplant setting. Given the invasive nature of biopsy, alternate means for accurately assessing liver fibrosis and steatosis are preferred especially as the number of patients with fatty liver disease is increasing. Transient elastography has been validated as a useful tool for evaluation of liver fibrosis, as has controlled attenuation parameter index as a tool for assessing steatosis. It is a non-invasive, rapid, and highly reproducible approach to demonstrate the presence of fibrosis among non-transplant patients with chronic liver disease of various etiologies. However, it has not yet found wide acceptance in liver transplant recipients. There are few published studies evaluating the merits and applicability of transient elastography to assess allografts after liver transplantation. We review the published data on the use of transient elastography with concurrent controlled attenuation parameter in liver transplant recipients and recommend its greater use to follow allograft function over time.

A Novel Non-invasive Method for Predicting Liver Fibrosis by Quantifying the Hepatic Vein Waveform

The hepatic vein (HV) waveform by Doppler ultrasound reflects the severity of liver fibrosis. We conducted a proof-of-concept study of a new method for quantifying the HV waveform. We calculated the coefficient of variation (CV) of the HV flow velocity and created a new index "q-HV" (quantified HV) and analyzed its performance for predicting histologic liver fibrosis in 114 patients with chronic liver disease. The CV of the HV flow velocity was well associated with flattening of the waveform and the q-HV significantly increased with the progression of liver fibrosis. The areas under the curve for the prediction of fibrosis stage were 0.732 for F2, 0.772 for F3 and 0.805 for F4. Combined q-HV and FIB-4 index (widely used liver fibrosis score) increased the diagnostic accuracy for liver fibrosis. The q-HV showed good accuracy for predicting liver fibrosis; thus, q-HV is feasible and acceptable as a non-invasive tool for predicting liver fibrosis.

Comparison of FibroTouch and FibroScan for staging fibrosis in chronic liver disease: Single-center prospective study

BACKGROUND

The aim of this study was to compare the diagnostic accuracy of the FibroTouch and FibroScan in patients with chronic liver disease (CLD) for staging fibrosis.

METHODS

A prospective study was conducted in 435 CLD patients between 2014 and 2017. Index tests (FibroTouch, FibroScan, APRI, and FIB-4 score) and a reference standard (liver biopsy) were performed within one week.

RESULTS

The area under the receiver operating curve (AUROC) of the FibroTouch was similar with that of the FibroScan for the diagnosis of significant fibrosis, severe fibrosis, or cirrhosis; however, the AUROC of the FibroTouch was higher than that of APRI or FIB-4 (p < 0.001). There was a significant correlation (rho = 0.85, p < 0.001) between the FibroTouch and FibroScan for liver stiffness. The overall diagnostic accuracy of FibroTouch for significant fibrosis, severe fibrosis, or cirrhosis was 73.3%, 83.2%, or 84.1%, respectively. No significant differences between the FibroTouch and FibroScan were detected regarding the sensitivity, specificity, negative predictive value, positive predictive value, and accuracy. The optimal cut-off values for each stage of fibrosis were similar between the FibroTouch and FibroScan.

CONCLUSION

The FibroTouch is a valuable diagnostic tool for diagnosing liver fibrosis with good diagnostic accuracy which was comparable with that of the FibroScan, but superior to that of the APRI and FIB-4.

CTHRC1 expression in primary biliary cholangitis

OBJECTIVES

Collagen triple helix repeat containing-1 (CTHRC1) is a highly conserved extracellular matrix glycoprotein that is overexpressed in two murine models of cholestatic liver fibrosis. Elevated CTHRC1 has been found to attenuate liver fibrosis in these murine models, thus we aimed to study the expression of CTHRC1 in patients with cholestatic liver diseases and its correlation with hepatic conditions.

METHODS

Ninety patients with chronic liver disease, including 48 had primary biliary cholangitis (PBC), 18 had primary sclerosing cholangitis (PSC) and 24 had chronic hepatitis B (CHB), together with five healthy controls (HC), were recruited to this study. Participants' liver sections were analyzed using immunohistochemistry. Serum CTHRC1 levels in another cohort of 59 patients with PBC and 10 age-matched HC were detected by enzyme-linked immunosorbent assay.

RESULTS

CTHRC1 protein was primarily expressed in activated hepatic stellate cells (HSC). CTHRC1 expression was significantly increased in the PBC and PSC groups, compared with the HC and CHB groups. Importantly, the hepatic fibrosis stage of the PBC group was positively correlated with hepatic CTHRC1 expression (r = 0.425, P = 0.003). Meanwhile, there were significant correlations between serum CTHRC1 levels and both the degrees of hepatic inflammation and fibrosis stage in the PBC group (r = 0.300, P = 0.022; r = 0.321, P = 0.012).

CONCLUSION

CTHRC1 may play a role in hepatic fibrogenesis in PBC and that serum CTHRC1 may be a potential novel noninvasive biomarker in the assessment of liver fibrosis and inflammation.

Usefulness of Transient Elastography for Non-Invasive Diagnosis of Liver Fibrosis in Pediatric Non-Alcoholic Steatohepatitis

BACKGROUND

Transient elastography (FibroScan®) is a non-invasive and rapid method for assessing liver fibrosis. While the feasibility and usefulness of FibroScan® have been proven in adults, few studies have focused on pediatric populations. We aimed to determine the feasibility and usefulness of FibroScan® in Korean children.

METHODS

FibroScan® examinations were performed in 106 children (age, 5-15 years) who visited the Konyang University Hospital between June and September 2018. Liver steatosis was measured in terms of the controlled attenuation parameter (CAP), while hepatic fibrosis was evaluated in terms of the liver stiffness measurement (LSM). Children were stratified into obese and non-obese controls, according to body mass index (≥ or < 95th percentile, respectively).

RESULTS

The obese group was characterized by significantly higher levels of aspartate aminotransferase (AST, 57.00 ± 48.47 vs. 26.40 ± 11.80 IU/L; P < 0.001) and alanine aminotransferase (ALT, 91.27 ± 97.67 vs. 16.28 ± 9.78 IU/L; P < 0.001), frequency of hypertension and abdominal obesity (abdominal circumference > 95% percentile) (P < 0.001), CAP (244.4-340.98 dB/m), and LSM (3.85-7.77 kPa) (P < 0.001). On FibroScan®, 30 of 59 obese children had fibrosis (LSM > 5.5 kPa), whereas the remaining 29 did not (LSM < 5.5 kPa). Obese children with fibrosis had higher levels of AST (73.57 ± 56.00 vs. 39.86 ± 31.93 IU/L; P = 0.009), ALT (132.47 ± 113.88 vs. 48.66 ± 51.29 IU/L; P = 0.001), and gamma-glutamyl transferase (106.67 ± 69.31 vs. 28.80 ± 24.26 IU/L; P = 0.042) compared to obese children without fibrosis. LSM had high and significant correlation (P < 0.05) with AST, ALT, homeostasis model assessment for insulin resistance, and AST-to-platelet ratio index.

CONCLUSION

FibroScan® is clinically feasible and facilitates non-invasive, rapid, reproducible, and reliable detection of hepatic steatosis and liver fibrosis in the Korean pediatric population.

Correlation of serum Mac-2-binding protein glycosylation isomer (M2BPGi) and liver stiffness in chronic hepatitis B infection

BACKGROUND AND AIM

Mac-2-binding protein glycosylation isomer (M2BPGi) is a novel serum diagnostic marker for liver fibrosis in various liver diseases. We aimed to evaluate its role in assessment of liver fibrosis in chronic hepatitis B infection (CHB) with reference to liver stiffness measurement (LSM).

METHODS

CHB patients with LSM by transient elastography technology and retrievable serum samples were recruited. Ten-year re-assessments of LSM and M2BPGi were repeated in a patient subgroup.

RESULTS

240 CHB patients (M:F = 116:124; median age 47.5 years) were recruited. The median M2BPGi values for F0/F1/F2, F3 and F4 progressively increased with more advanced stages of liver fibrosis: 0.39, 0.46 and 0.82 COI, respectively (p < 0.01). M2BPGi levels correlated well with liver stiffness (r = 0.611), FIB-4 (r = 0.616), and strongly with APRI (r = 0.825) (all p < 0.001). Using cut-off values of 0.605 and 0.615 COI, the AUROCs were 0.754 and 0.799 for ≥ F3 and F4, respectively. M2BPGi identified one-quarter patients at risk of advanced fibrosis/cirrhosis otherwise classified into 'grey area' by LSM. In 86 patients with reassessment LSM, 21 (24.4%) showed significant fibrosis regression with corresponding decline in median M2BPGi level (- 0.11 COI) compared with the increase of +0.03 COI in patients without significant fibrosis regression (p = 0.011). Male gender, older age, use of potent antiviral therapy and change in serum M2BPGi were independently associated with significant fibrosis regression.

CONCLUSIONS

Serum M2BPGi can risk-stratify CHB patients whose liver stiffness fell into the 'grey area'. Significant fibrosis regression occurring in one-quarter patients was reflected by a reduction in M2BPGi levels at 10-year interval.

Feasibility and Efficacy of Transient Elastography using the XL probe to diagnose liver fibrosis and cirrhosis: A meta-analysis

BACKGROUND

Transient elastography (TE) has been validated as an effective noninvasive tool for the assessment of liver fibrosis. The XL probe is a new probe that was initially designed for use in patients with obesity. A meta-analysis was performed to assess the feasibility and efficacy of TE using the XL probe.

METHODS

In September 2016, we systematically searched the PubMed and Science Direct search engines. The feasibility of TE was evaluated based on the failure rate and the results of the unreliable liver stiffness measurement (LSM). The efficacy of TE was measured using sensitivity, specificity, and summary receiver-operating characteristic as measures/indices assessed in different stages of fibrosis. Heterogeneity was measured using the chi-squared test and the Q-statistic. We used the 95% confidence interval (95% CI) as an effect measure.

RESULTS

We included 8 studies in the meta-analysis. When the XL was compared to the M probe, the former showed a lower risk of failure rate [relative risk (RR) 0.24, 95% CI 0.14-0.38]. In patients with a body mass index ≥30 kg/m, the XL probe showed a statistically significantly lower risk of failure rate (RR 0.16, 95% CI 0.08-0.32) but no significant improvement (RR 0.76, 95% CI 0.50-1.16) in the unreliable LSM result. In patients showing liver fibrosis stage ≥F2, the XL probe showed a sensitivity of 0.56 (95% CI 0.39-0.72), specificity of 0.71 (95% CI 0.61-0.79), and an area under the curve (AUC) of 0.71. The results observed in patients with liver fibrosis stage F4 were more promising with a sensitivity of 0.84 (95% CI 0.76-0.90), specificity of 0.78 (95% CI 0.70-0.84), and an AUC of 0.88.

CONCLUSION

TE using the XL probe demonstrates significant diagnostic utility in patients with liver fibrosis and is likely to be more reliable than the M probe in patients with obesity. Large prospective multicenter studies are, however, necessary to establish the new cut-off values to be used for the XL probe in patients with obesity.

Chronic Hepatitis C Patients with Obesity: Do we Need two Operators for Accurate Evaluation of Liver Stiffness?

INTRODUCTION AND AIM

Transient elastography is gaining popularity as a non-invasive method for predicting liver fibrosis, but inter observer agreement and factors influencing reproducibility have not been adequately assessed.

MATERIAL AND METHODS

This cross-sectional study was conducted at Specialized Medical Hospital and the Egyptian Liver Foundation, Mansoura, Egypt. The inclusion criteria were: age older than 18 years and chronic infection by hepatitis C. The exclusion criteria were the presence of ascites, pacemaker or pregnancy. Three hundred and fifty-six patients participated in the study. Therefore, 356 pairs of exams were done by two operators on the same day.

RESULTS

The overall inter observer agreement ICC was 0.921. The correlation the two operators was excellent (Spearman's value q = 0.808, p < 0.001). Inter-observer reliability values were κ = 0.557 (p < 0.001). A not negligible discordance of fibrosis staging between operators was observed (87 cases, 24.4%). Discordance of at least one stage and for two or more stages of fibrosis occurred in 60 (16.9%) and 27 cases (7.6%) respectively. Obesity (BMI ≥ 30 kg/m2) is the main factor associated with discordance (p = 0.002).

CONCLUSION

Although liver stiffness measurement has had an excellent correlation between the two operators, TE presented an inter-observer variability that may not be negligible.

Diagnostic accuracy of point shear wave elastography and transient elastography for staging hepatic fibrosis in patients with non-alcoholic fatty liver disease: a meta-analysis

OBJECTIVE

This study aimed to assess the accuracy of staging liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) usingpoint shear wave elastography (pSWE) and transient elastography (TE).

SETTING

Relevant records on NAFLD were retrieved from PubMed, Embase, Web of Science and the China National Knowledge Infrastructure databases up to 20 December 2017. A bivariate mixed-effects model was conducted to combine sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and area under the summary receiver operating characteristic curve (AUC) between pSWE and TE. A sensitivity analysis was implemented to explore the source of heterogeneity.

PARTICIPANTS

Patients with NAFLD who had a liver stiffness measurement using pSWE and TE before liver biopsy were enrolled according to the following criteria: 2×2 contingency tables can be calculated via the reported number of cases; sensitivity and specificity were excluded according to the following criteria: history of other hepatic damage, such as chronic hepatitis C, concurrent active hepatitis B infection, autoimmune hepatitis, suspicious drug usage and alcohol abuse.

RESULTS

Nine pSWE studies comprising a total of 982 patients and 11 TE studies comprising a total of 1753 patients were included. For detection of significant fibrosis, advanced fibrosis and cirrhosis, the summary AUC was 0.86 (95% CI 0.83 to 0.89), 0.94 (95% CI 0.91 to 0.95) and 0.95 (95% CI 0.93 to 0.97) for pSWE, and the summary AUC was 0.85 (95% CI 0.82 to 0.88), 0.92 (95% CI 0.89 to 0.94) and 0.94 (95% CI 0.93 to 0.97) for TE, respectively. The proportion of failure measurement was over tenfold as common with TE using an M probe compared with pSWE.

CONCLUSION

pSWE and TE, providing precise non-invasive staging of liver fibrosis in NAFLD, are promising techniques, particularly for advanced fibrosis and cirrhosis.

The role of imaging in prediction of post-hepatectomy liver failure

Post-hepatectomy liver failure (PHLF) is not only a leading cause of mortality but also a leading cause of life-threatening complications in patients undergoing liver resection. The ability to accurately detect the emergence of PHLF represents a crucially important step. Currently, PHLF can be predicted by a comprehensive evaluation of biological, clinical, and anatomical parameters. With the development of new technologies, imaging methods including elastography, diffusion-weighted magnetic resonance imaging, and gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid-enhanced MRI play a more significant role in the pre-operative prediction and assessment of PHLF. In this review, we summarize the mainstream studies, with the aim of evaluating the role of imaging and improving the clinical value of existing scoring systems for predicting PHLF.

Non-invasive assessments for liver fibrosis: The crystal ball we long for

Non-invasive assessment of liver fibrosis has been one of the most rapidly advancing fields in hepatology in the last decade. Progressive liver fibrosis results in cirrhosis, hepatocellular carcinoma (HCC), and various liver-related complications in essentially all chronic liver diseases. Assessment of liver fibrosis allows clinicians to determine the prognosis, need of treatment, disease progression, and response to treatment in patients with chronic liver disease. Liver biopsy has been the gold standard in last few decades and most adopted diagnostic tool in clinical trials. Nonetheless, it is impractical to apply the test in a large number of patients or to do it serially. Hence, various non-invasive assessments have been developed and adopted in some international management guidelines. Liver stiffness measurement (LSM) with transient elastography is one of the most widely validated non-invasive assessments for liver fibrosis. It is an accurate and reproducible method to predict advanced fibrosis in chronic hepatitis B. Using transient elastography, it is possible to perform repeated liver fibrosis assessments on a large number of asymptomatic patients. The key challenge of his tool is the confounding effect of alanine aminotransferase (ALT) level, such that decrease in LSM may only reflect ALT normalization, hence not accurate enough to indicate regression of liver fibrosis. This may be partially handled by combining LSM with a serum-based formula, which is independent of ALT such as the Forns index and enhanced liver fibrosis test. An LSM-based HCC risk score is useful to prioritize patients for HCC surveillance.

Liver sampling: a vital window into HBV pathogenesis on the path to functional cure

In order to optimally refine the multiple emerging drug targets for hepatitis B virus (HBV), it is vital to evaluate virological and immunological changes at the site of infection. Traditionally liver biopsy has been the mainstay of HBV disease assessment, but with the emergence of non-invasive markers of liver fibrosis, there has been a move away from tissue sampling. Here we argue that liver biopsy remains an important tool, not only for the clinical assessment of HBV but also for research progress and evaluation of novel agents. The importance of liver sampling has been underscored by recent findings of specialised subsets of tissue-resident immune subsets capable of efficient pathogen surveillance, compartmentalised in the liver and not sampled in the blood. Importantly, the assessment of virological parameters, such as cccDNA quantitation, also requires access to liver tissue. We discuss strategies to maximise information obtained from the site of infection and disease pathology. Fine needle aspirates of the liver may allow longitudinal sampling of the local virus/host landscape. The careful utilisation of liver tissue and aspirates in conjunction with blood will provide critical information in the assessment of new therapeutics for the functional cure of HBV.

A Prospective Blinded Study of Endoscopic Ultrasound Elastography in Liver Disease: Towards a Virtual Biopsy

Background/Aims

Liver biopsy has traditionally been used for determining the degree of fibrosis, however there are several limitations. Endoscopic ultrasound (EUS) real-time elastography (RTE) is a novel technology that uses image enhancement to display differences in tissue compressibility. We sought to assess whether liver fibrosis index (LFI) can distinguish normal, fatty, and cirrhotic liver tissue.

Methods

A total of 50 patients undergoing EUS were prospectively enrolled. RTE of the liver was performed to synthesize the LFI in each patient. Univariate and multivariable analyses were performed. Chi-square and t-tests were performed for categorical and continuous variables, respectively. A p-value of <0.05 was considered significant.

Results

Abdominal imaging prior to endoscopic evaluation suggested normal tissue, fatty liver, and cirrhosis in 26, 16, and 8 patients, respectively. Patients with cirrhosis had significantly increased mean LFI compared to the fatty liver (3.2 vs. 1.7, p<0.001) and normal (3.2 vs. 0.8, p<0.001) groups. The fatty liver group showed significantly increased LFI compared to the normal group (3.8 vs. 1.4, p<0.001). Multivariable regression analysis suggested that LFI was an independent predictor of group features (p<0.001).

Conclusions

LFI computed from RTE images significantly correlates with abdominal imaging and can distinguish normal, fatty, and cirrhotic-appearing livers; therefore, LFI may play an important role in patients with chronic liver disease.

Assessment of liver fibrosis in Egyptian chronic hepatitis B patients: A comparative study including 5 noninvasive indexes

Fibrosis assessment in chronic hepatitis B (CHB) is essential for prediction of long-term prognosis and proper treatment decision. This study was conducted to assess predictability of 5 simple noninvasive fibrosis indexes in comparison to liver biopsy in CHB patients.A total of 200 CHB adult Egyptian patients were consecutively included in this study, all were subjected to liver biopsy with staging of fibrosis using METAVIR scoring system. Fibrosis indexes including S-index, red cell distribution width to platelets ratio index (RPR), fibrosis-4 index (Fib-4), AST to platelets ratio index (APRI), and AST/ALT ratio index (AAR) were compared to biopsy result and their predictabilities for the different fibrosis stages were assessed using area under receiver operating characteristic curve (AUROC) analysis.S-index showed the highest AUROCs for predicting fibrosis among the studied indexes. AUROCs of S-index, RPR, Fib-4, APRI, and AAR were: 0.81, 0.67, 0.70, 0.68, and 0.60 for prediction of significant fibrosis (F2-F4), 0.90, 0.66, 0.68, 0.67, and 0.57 for advanced fibrosis (F3-F4), and 0.96, 0.62, 0.61, 0.57, and 0.53 for cirrhosis (F4), respectively. The optimal S-index cutoff for ruling in significant fibrosis was ≥0.3 with 94% specificity, 87% PPV, and 68% accuracy, while that for ruling out significant fibrosis was <0.1 with 96% sensitivity, 91% NPV, and 67% accuracy. Accuracy of S-index was higher for predicting cirrhosis (91%) than that for predicting advanced fibrosis (79%) and significant fibrosis (68%).S-index has the highest predictability for all fibrosis stages among the studied fibrosis indexes in HBeAg-negative CHB patients, with higher accuracy in cirrhosis than in the earlier fibrosis stages.

Prognostic value of liver stiffness measurement for the liver-related surgical outcomes of patients under hepatic resection: A meta-analysis

BACKGROUND

Previous studies have discussed the liver stiffness measurement (LSM) performance on predicting liver-related surgical outcomes for patients of hepatocellular carcinoma (HCC) under hepatic resection, yet there is much variation in reporting and consistency of findings. Therefore, we report a meta-analysis on this issue.

METHODS

We comprehensively searched PubMed, Embase, and Web of science to find the eligible cohort studies. The pooled Odds Ratios (OR) and 95% confidence intervals (CIs) were calculated to evaluate effect. The weighted mean LSM value was calculated as the optimal LSM cut-off value among studies.

RESULTS

12 prospective cohort studies and one retrospective cohort study, including a total of 1942 cases were identified. The pooled results showed that preoperative LSM is significantly associated with the occurrence of overall postoperative complications (OR 1.76, 95% CI 1.46-2.11). In addition, a weighted mean LSM value of 14.2 kPa and 11.3KPa were suggested as the optimal LSM cut-off value reference using transient elastoqraphy (TE) for predicting overall postoperative complications in Asia countries and European countries, respectively.

CONCLUSIONS

Preoperative LSM should be taken into account cautiously in the management of patients undergoing hepatectomy of HCC. Future studies could focus on setting a prognostic model integrated with LSM in predicting post-hepatectomy outcomes.

A noninvasive diagnosis of hepatic fibrosis by BioFibroScore® in chronic hepatitis C patients

BACKGROUND AND AIMS

The diagnostic accuracy of a novel serological panel (BioFibroScore®) to predict hepatic fibrosis in patients with chronic hepatitis C virus (HCV) infection is unknown.

METHODS

Three markers of BioFibroScore, including urokinase plasminogen activator, matrix metalloproteinase-9, and beta-2 microglobulin, were retrospectively evaluated in 635 HCV-infected patients who received percutaneous liver biopsy and FibroScan®. The formula of BioFibroScore to predict the severity of hepatic fibrosis was developed by adaptive boosting algorithm. The diagnostic accuracy of hepatic fibrosis was assessed both for BioFibroScore and FibroScan, taking METAVIR fibrosis score as the reference standard.

RESULTS

Urokinase plasminogen activator and beta-2 microglobulin were positively and matrix metalloproteinase-9 was negatively associated with the severity of hepatic fibrosis. Thirty-five (5.5%) patients had failed FibroScan assessment. By adaptive boosting model for BioFibroScore and the established reference ranges for FibroScan, 85.7% and 89.0% of the patients had an identical result for F0-1, F2, F3, and F4, as compared with liver biopsy. The concordance rate between BioFibroScore and FibroScan was 80.7%. BioFibroScore overestimated and underestimated the stage of hepatic fibrosis in 8.3% and 6.0% patients, and most patients had one stage error. Among patients with failed FibroScan assessment, 82.9% of them were correctly diagnosed by BioFibroScore. Bootstrap analysis for BioFibroScore showed the diagnostic accuracy was 80.9-88.4%.

CONCLUSIONS

BioFibroScore is accurate to assess the stage of hepatic fibrosis in HCV-infected patients. Applying this noninvasive test can substantially reduce the need for invasive liver biopsy and can play a role for fibrosis evaluation when FibroScan assessment was unavailable or unreliable.

Clinical Application of Vibration Controlled Transient Elastography in Patients with Chronic Hepatitis B

Evaluation of the extent and progression of liver fibrosis and cirrhosis is of critical importance in the management and prognosis of patients with chronic hepatitis B. Due to the limitation of liver biopsy, non-invasive methods, especially liver stiffness measurement (LSM) by vibration controlled transient elastography, have been developed and widely applied for liver fibrosis assessment. LSM aims to reduce, but not to substitute, the need for liver biopsy for fibrosis/cirrhosis diagnosis. While LSM may have potential utility in monitoring treatment response, its applications in prediction of liver complications in terms of portal hypertension and esophageal varices, as well as disease prognosis, have been gradually validated. Here, we review the latest clinical applications of LSM in patients with chronic hepatitis B.

Prospective comparison among transient elastography, supersonic shear imaging, and ARFI imaging for predicting fibrosis in nonalcoholic fatty liver disease

The diagnostic performance of supersonic shear imaging (SSI) in comparison with those of transient elastography (TE) and acoustic radiation force impulse imaging (ARFI) for staging fibrosis in nonalcoholic fatty liver disease (NAFLD) patients has not been fully assessed, especially in Asian populations with relatively lean NAFLD compared to white populations. Thus, we focused on comparing the diagnostic performances of TE, ARFI, and SSI for staging fibrosis in a head-to-head manner, and identifying the clinical, anthropometric, biochemical, and histological features which might affect liver stiffness measurement (LSM) in our prospective biopsy-proven NAFLD cohort. In this study, ninety-four patients with biopsy-proven NAFLD were included prospectively. Liver stiffness was measured using TE, SSI, and ARFI within 1 month of liver biopsy. The diagnostic performance for staging fibrosis was assessed using receiver operating characteristic (ROC) analysis. Anthropometric data were evaluated as covariates influencing LSM by regression analyses. Liver stiffness correlated with fibrosis stage (p < 0.05); the area under the ROC curve of TE (kPa), SSI (kPa), and ARFI (m/s) were as follows: 0.757, 0.759, and 0.657 for significant fibrosis and 0.870, 0.809, and 0.873 for advanced fibrosis. Anthropometric traits were significant confounders affecting SSI, while serum liver injury markers significantly confounded TE and ARFI. In conclusion, the LSM methods had similar diagnostic performance for staging fibrosis in patients with NAFLD. Pre-LSM anthropometric evaluation may help predict the reliability of SSI.

The non-invasive serum biomarker soluble Axl accurately detects advanced liver fibrosis and cirrhosis

Soluble Axl (sAxl) was recently shown to be strongly released into the blood during liver fibrogenesis and hepatocellular carcinoma suggesting sAxl as a biomarker of liver diseases. In this study we are the first to evaluate sAxl in human serum in comparison to Enhanced Liver Fibrosis (ELF) test and transient elastography (TE; Fibroscan) for its value to detect significant (F≥2), advanced fibrosis (F≥3), and cirrhosis (F4) in different liver disease etiologies and healthy controls. To properly determine the diagnostic accuracy of sAxl, a test cohort as well as a validation cohort was employed using liver biopsy as a reference method. Most notably, sAxl was confirmed to be an accurate biomarker of liver fibrosis and cirrhosis. Its accuracy was increased, if total serum albumin was added to build a sAxl/albumin ratio. Thereby an AUC of 0.763, 0.776, 0.826, and 0.832 was achieved corresponding to histological fibrosis stages F≥2, F≥3, F4 with liver biopsy as a reference method, and cirrhosis according to imaging techniques, respectively. With a cut-off of 1.29, a sensitivity, specificity, PPV, and NPV of 78.5%, 80.1%, 44%, 94.9% for the detection of cirrhosis was achieved. In comparison, ELF test and TE showed an AUC of 0.910, and 0.934, respectively, for the detection of cirrhosis. However, performance of TE was not possible in 14.4% of patients and both, ELF™ test and TE bear the disadvantage of high costs. In conclusion, the sAxl/albumin ratio is suggested as an accurate biomarker of liver fibrosis and cirrhosis. Due to its easy applicability and low costs it is suitable as screening parameter for significant to advanced liver fibrosis and cirrhosis, especially if TE is not available or not applicable.

Impact of hepatitis C virus genotype-4 eradication following direct acting antivirals on liver stiffness measurement

Background

Liver fibrosis is the most important prognostic factor in chronic hepatitis C virus (HCV) patients, and Egypt shows the highest worldwide HCV prevalence with genotype-4 pre-dominance. The aim of this study was to investigate the degree of liver stiffness measurement (LSM) improvement after successful HCV eradication.

Patients and methods

The study included 84 chronic HCV Egyptian patients, and was conducted at Qena University Hospital from November 1, 2015 till October 31, 2016. LSM was obtained by FibroScan® before starting direct acting antiviral (DAA) treatment and after achieving sustained virologic response-24 (SVR-24). Based on baseline LSM, patients were stratified into F0–F1, F2, F3 and F4 groups (METAVIR). LSM and laboratory data after achieving SVR-24 was compared with that before starting therapy in each fibrosis group (F0-F4), p-value <0.05 was statistically significant.

Results

Following DAA treatment, 80 patients achieved SVR-24; of these, 50 were males (62.5%), mean age: 54.2±7.6 years, and mean body mass index: 28.6±2.2 kg/m². Mean baseline LSM dropped from 15.6±10.8 to 12.1±8.7 kPa post-SVR; the maximum change of −5.8 occurred in F4 versus −2.79, −1.28 and +0.08 in F3, F2 and F0–F1 respectively (p<0.0001). At baseline, 41 patients were in the F4 group; only 16 (39%) regressed to non-cirrhotic range (<12.5 kPa), while 25 (61%) were still cirrhotic despite achieving SVR-24 (p<0.0001). Patients who achieved LSM improvement (n=64) have had significantly higher baseline aspartate transferase (AST) and alanine transaminase (ALT). Also, those patients showed significant improvement in AST, AST/platelets ratio index (APRI) and fibrosis-4 index (Fib-4) after achieving SVR; 91% showed AST improvement (p=0.01) and APRI improvement (p=0.01) and 81% showed Fib-4 improvement (p=0.04). Females, diabetics, patients with S3 steatosis and patients older than 50 years showed less LSM improvements than their counterparts. Baseline LSM ≥9 kPa, bilirubin ≥1 mg/dl, ALT ≥36 U/L and AST ≥31 U/L were significant predictors for LSM improvement.

Conclusion

Successful HCV genotype-4 eradication results in significant LSM improvement; the best improvement occurs in F4 patients. But as the majority of cirrhotics are still at risk for liver decompensation and hepatocellular carcinoma development despite achieving SVR-24, early detection and treatment are highly recommended.

Current Modalities of Fibrosis Assessment in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a burgeoning global health concern. In the subset of NAFLD patients with non-alcoholic steatohepatitis (NASH), the presence of significant fibrosis at index assessment is associated with poor prognosis and increased mortality. Hence, there is a growing need to accurately assess and stage fibrosis. Liver biopsy, the current gold standard, has limitations with sampling error and is invasive, with associated inherent risk. This has led to a host of non-invasive means of assessing fibrosis, which has garnered relevance in a disease that requires serial assessment of fibrosis longitudinally over time. This review discusses, comprehensively, the various tools available to the clinician for the assessment of fibrosis, including the various scoring systems used in liver biopsy, the non-invasive means of serum biomarkers, such as the highly-validated NAFLD fibrosis score, and the imaging-based modalities, such as transient elastography and magnetic resonance elastography.

Th17/Treg imbalance is an indicator of liver cirrhosis process and a risk factor for HCC occurrence in HBV patients

OBJECTIVE

To determine the impact of T helper 17 cell (Th17)/regulatory T cell (Treg) ratio imbalance on the process and prognosis of hepatitis B virus (HBV)-related liver cirrhosis.

METHODS

Patients with HBV who refused to accept any therapy from were recruited from 2009 to 2014 and followed-up to August 2016. Based on a liver stiffness measurement (LSM), the patients were divided into a low LSM group and a high LSM group. After propensity score matching, 150 patients were included. The peripheral blood of all subjects was tested using a flow cytometer to measure the Th17 and Treg cell frequencies and the Th17/Treg ratio. Spearman rank correlation, log-rank test, Cox regression model, and receiver operating characteristic (ROC) curves were applied to analyze the correlation between the Th17/Treg ratio and LSM level and the risk factors of HCC occurrence and to predict the Th17/Treg ratio for the LSM level.

RESULTS

Th17 and Treg cell frequencies and the Th17/Treg ratio were significantly different between the low and high LSM groups. The Th17/Treg ratio showed a strong positive association with LSM level (r=0.631, P<0.01). Furthermore, the Th17/Treg ratio was an independent factor influencing the HCC occurrence, which was tested using a Cox regression model. The area under the ROC curve of the Th17/Treg ratio for predicting LSM level was 0.783 (95% CI 0.705-0.861).

CONCLUSION

Th17/Treg ratio imbalance is an indicator of the liver cirrhosis process and a risk factor for HCC occurrence in patients infected with HBV.