Performance of liver stiffness measurements by transient elastography in chronic hepatitis

Imaging-based noninvasive liver disease assessment for staging liver fibrosis in chronic liver disease: A systematic review supporting the AASLD Practice Guideline

BACKGROUND AND AIMS

Transient elastography (TE), shear wave elastography, and/or magnetic resonance elastography (MRE), each providing liver stiffness measurement (LSM), are the most studied imaging-based noninvasive liver disease assessment (NILDA) techniques. To support the American Association for the Study of Liver Diseases guidelines on NILDA, we summarized the evidence on the accuracy of these LSM methods to stage liver fibrosis (F).

APPROACH AND RESULTS

A comprehensive search for studies assessing LSM by TE, shear wave elastography, or MRE for the identification of significant fibrosis (F2-4), advanced fibrosis (F3-4), or cirrhosis (F4), using histopathology as the standard of reference by liver disease etiology in adults or children from inception to April 2022 was performed. We excluded studies with <50 patients with a single disease entity and mixed liver disease etiologies (with the exception of HCV/HIV coinfection). Out of 9447 studies, 240 with 61,193 patients were included in this systematic review. In adults, sensitivities for the identification of F2-4 ranged from 51% to 95%, for F3-4 from 70% to 100%, and for F4 from 60% to 100% across all techniques/diseases, whereas specificities ranged from 36% to 100%, 74% to 100%, and 67% to 99%, respectively. The largest body of evidence available was for TE; MRE appeared to be the most accurate method. Imaging-based NILDA outperformed blood-based NILDA in most comparisons, particularly for the identification of F3-4/F4. In the pediatric population, imaging-based NILDA is likely as accurate as in adults.

CONCLUSIONS

LSM from TE, shear wave elastography, and MRE shows acceptable to outstanding accuracy for the detection of liver fibrosis across various liver disease etiologies. Accuracy increased from F2-4 to F3-4 and was the highest for F4. Further research is needed to better standardize the use of imaging-based NILDA, particularly in pediatric liver diseases.

The impact of vildagliptin as an add-on therapy on matrix metalloproteinase-14 levels, liver stiffness and subclinical atherosclerosis in adolescents with type 1 diabetes and non-alcoholic steatohepatitis: A randomized controlled trial

AIM

Many patients with type 1 diabetes mellitus (T1DM) met the histological criteria for non-alcoholic steatohepatitis (NASH), which leads to cardiovascular disease morbidity and mortality. Matrix metalloproteinase-14 (MMP-14) is involved in cardiovascular disease and atherosclerosis.

OBJECTIVES

To assess the impact of oral dipeptidyl peptidase-4 inhibitor, vildagliptin, as adjunctive therapy on NASH in adolescents with T1DM and its effect on glycaemic control, MMP-14 levels and carotid intima media thickness (CIMT).

METHODS

Sixty adolescents with T1DM and NASH were randomly assigned to receive oral vildagliptin (50 mg once daily) for 6 months or not. Glycated haemoglobin, lipid profile, hepatic steatosis index, triglyceride glucose (TyG) index and MMP-14 levels were assessed. Transient elastography with controlled attenuation parameter (CAP) was performed together with measuring CIMT.

RESULTS

By transient elastography, 12 (20%) patients with T1DM with NASH had elevated liver stiffness ≥7 kPa (F2 stage or higher). Baseline MMP-14 was positively correlated to insulin dose (p = 0.016), triglycerides and TyG index, CIMT, liver stiffness and CAP levels among the studied patients (p < 0.001 for all). After 6 months, patients with T1DM on vildagliptin therapy had significantly lower glycated haemoglobin, lipid profile, hepatic steatosis index and TyG index, as well as MMP-14 (p < 0.001). CIMT, liver stiffness and CAP were significantly decreased post-therapy compared with baseline levels and compared with the control group (p < 0.001). Vildagliptin was safe and well-tolerated.

CONCLUSIONS

Administration of vildagliptin for adolescents with T1DM and NASH improved glycaemic control, dyslipidaemia and MMP-14 levels and decreased liver stiffness and CIMT; hence, reducing subclinical atherosclerosis and disease progression.

Comparison of Transient Elastography and Point Shear Wave Elastography for Analysis of Liver Stiffness: A Prospective Study

Liver stiffness measurement (LSM) by Fibroscan is the most used non-invasive method to assess liver fibrosis. Recently, point-shear wave elastography (pSWE) has been introduced as a simple alternative non-invasive test. Therefore, we aimed to compare the results of these two techniques. One hundred and eighty-four consecutive patients attending our outpatient ultrasound clinic were recruited. LSM was performed by both Fibroscan and pSWE. Statistical analysis was conducted by Spearman's test for correlation and linear regression. Bland-Altman graphs and ROC curves were drawn with area under the curve (AUC). Overall, the correlation of LS between Fibroscan and pSWE was substantial (r = 0.68, p < 0.001). Linear regression showed a coefficient b= 0.94 ± 0.02. The Bland-Altman plot found a bias of -0.10, with only 11 values exceeding the 95% confidence interval. When only considering patients with a LSM of > 10 kPa (n = 31), we found an excellent r = 0.79 (0.60-0.90, p < 0.001). A cutoff of 12.15 kPa for pSWE had sensitivity = 74.2% and specificity = 99.3% to detect relevant fibrosis, with an AUC = 0.98. The highest correlation was observed for hepatitis C (r = 0.91) and alcoholic liver disease (ALD)(r = 0.99). In conclusion, pSWE shows LSM estimation in agreement with Fibroscan in most cases, and the best concordance was observed for hepatitis C and ALD, and for higher ranges of LS.

Non-Invasive Measurement of Hepatic Fibrosis by Transient Elastography: A Narrative Review

Transient elastography by FibroScan® (Echosens, Paris, France) is a non-invasive method that can provide a reliable measurement of liver fibrosis through the evaluation of liver stiffness. Despite its limitations and risks, liver biopsy has thus far been the only procedure able to provide data to quantify fibrosis. Scientific evidence and clinical practice have made it possible to use FibroScan® in the diagnostic work-up of several liver diseases to monitor patients' long-term treatment response and for complication prevention. For these reasons, this procedure is widely used in clinical practice and is still being investigated for further applications. The aim of this narrative review is to provide a comprehensive overview of the main applications of transient elastography in the current clinical practice.

Distinct Expression Patterns of Genes Coding for Biological Response Modifiers Involved in Inflammatory Responses and Development of Fibrosis in Chronic Hepatitis C: Upregulation of SMAD-6 and MMP-8 and Downregulation of CAV-1, CTGF, CEBPB, PLG, TIMP-3, MMP-1, ITGA-1, ITGA-2 and LOX

Background and Objectives: The aim of this study was to analyze the expression of genes on transcriptomic levels involved in inflammatory immune responses and the development of fibrosis in patients with chronic hepatitis C. Materials and Methods: Expression patterns of 84 selected genes were analyzed with real-time quantitative RT PCR arrays in the peripheral blood of treatment-naive patients with chronic hepatitis C and healthy controls. The panel included pro- and anti-fibrotic genes, genes coding for extracellular matrix (EMC) structural constituents and remodeling enzymes, cell adhesion molecules, inflammatory cytokines, chemokines and growth factors, signal transduction members of the transforming growth factor- beta (TGF-ß) superfamily, transcription factors, and genes involved in epithelial to mesenchymal transition. Results: The expression of SMAD-6 coding for a signal transduction TGF-beta superfamily member as well as MMP-8 coding for an ECM protein were significantly increased in CHC patients compared with controls. Conclusions: Chronic hepatitis C was also characterized by a significant downregulation of a set of genes including CAV-1, CTGF, TIMP-3, MMP-1, ITGA-1, LOX, ITGA-2, PLG and CEBPB encoding various biological response modifiers and transcription factors. Our results suggest that chronic hepatitis C is associated with distinct patterns of gene expression modulation in pathways associated with the regulation of immune responses and development of fibrosis.

Comparing shear wave elastography with liver biopsy in the assessment of liver fibrosis at King Hussein Medical Center

Background and study aims

The aim of this prospective study is to compare the sensitivity and specificity of the liver shear wave elastography to the golden standard liver biopsy in staging liver fibrosis.

Patients and methods

Ninety-five patients were included in this study. These patients were sent for liver biopsy as a possible living liver donor or because of different pathologies including viral and autoimmune hepatitis and congenital liver diseases. A shear wave elastography and US-guided liver biopsy were done at the same setting by one experienced radiologist. One experienced histopathologist, blinded to SWE results, read the specimens.

Results

We included 95 patients in the study with a mean age of 30 years (range 3–65 years). We had 15/95 (16%) patients with hepatitis B/C, 61/95 (64%) patients with another liver disease, and 19/95 (20%) were donors. The mean of liver stiffness measured by elastography in patients was 6.5±0.19 kPa. The mean liver stiffness measured by elastography in patients with F0–F1 fibrosis was 5.39 ± 0.62 kPa, F2 was 7.32 ± 0.41, at stage F3 was 8.46 ± 0.33, and in the F4 stage, it was 11.42 ± 2.8 kPa. We found a significant difference in the mean level of liver stiffness in different degrees of fibrosis (p = 0.0001).

Conclusion

The shear wave elastography could be used to assess liver fibrosis regardless of the cause.

Multi-scale information with attention integration for classification of liver fibrosis in B-mode US image

BACKGROUND AND OBJECTIVE

Chronic hepatitis B (CHB) is one of the most common liver diseases in the world, which threats a lot to people's usual life. The increased deposition of fibrotic tissues in livers for patients with CHB may lead to the development of liver cirrhosis, hepatocellular carcinoma, or even liver failure. Accurate fibrosis staging is very important for the targeted treatment of liver fibrosis and its recovery.

METHODS

In this paper, we propose a new deep convolutional neural network (DCNN) with functions of multi-scale information extraction and attention integration for more accurate liver fibrosis classification from ultrasound (US) images. The proposed network uses two pyramid-structured CNN elements to extract multi-scale features from US images. Such a design significantly enlarges the receptive field of the convolution layer, such that more useful information can be explored by the neural network to associate with the final classification. Based on this, a new feature distillation method is also proposed to enhance the ability of deep features derived from multi-scale information. The proposed distillation method employs attention maps to automatically extract class-related features from multi-scale information, which effectively suppress the influence of potential distractors.

RESULTS

Experimental results on the US liver fibrosis dataset collected from 286 participants show that the proposed deep framework achieves promising classification performance. The proposed method achieves a classification accuracy of 95.66% on the test dataset.

CONCLUSION

Our proposed framework could stage liver fibrosis highly accurately. It might provide effective suggestions for the clinical treatment of liver fibrosis that can facilitate its recovery.

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.

Dynamics of APRI and FIB-4 in HCV cirrhotic patients who achieved SVR after DAA therapy

There are limited data available on the regression of fibrosis in hepatitis C virus (HCV) patients who have achieved sustained virologic response (SVR) after interferon-free treatments. Moreover, a perfect method for assessing liver fibrosis and its dynamics has not been established yet. The main objective of this study was to evaluate the dynamics of aspartate aminotransferase to platelet ratio index (APRI) and Fibrosis-4 (FIB-4) scores in patients with HCV who registered SVR. We performed ROC curve analysis to evaluate the diagnostic performance of APRI and FIB-4 scores in determining the presence of cirrhosis in comparison to FibroTest. In total 251 patients were enrolled: 164 cirrhotic and 83 non-cirrhotic patients, and they were evaluated at baseline, at 6 and at 12 months post-end of treatment (EOT). In the cirrhotic group, at baseline, there was a weak but statistically significant correlation between APRI and FibroTest (τ=0.173, P=0.001), as well as between FIB-4 and FibroTest (τ=0.265, P<0.001). At the 6-month follow-up, APRI no longer correlated with FibroTest (τ=0.144, P=0.057), while FIB-4 was correlated (τ=0.256, P=0.001). The same pattern was shown at 12 months post-EOT. Between baseline and the 6-month evaluation, there was a significant decrease in APRI (P<0.001) and FIB-4 (P<0.001) scores, but for the next follow-up period, there was no reduction. In the non-cirrhotic group, APRI and FIB-4 did not correlate with the FibroTest value at any of the evaluation times. There was a significant difference between baseline and the 6-month visit for APRI (P=0.01) and for FIB-4 (P=0.014). The areas under the receiver operating characteristics curve (AUROCs) for the presence of cirrhosis compared with FibroTest for APRI and FIB-4 were 0.682 [95% confidence interval (CI), 0.613-0.752] and 0.693 (95% CI 0.625-0.76). Both APRI and FIB-4 prove to be easy, quick and inexpensive tools for screening HCV cirrhosis, with moderate diagnostic accuracy and FIB-4 can be useful for monitoring patients post-EOT.

Usefulness of controlled attenuation parameter and liver stiffness measurement for detecting increased arterial stiffness in asymptomatic populations in China

In recent studies, vibration-controlled transient elastography (FibroScan) has been reported as an alternative noninvasive approach for measuring liver steatosis and fibrosis. The present study aimed to investigate the feasibility of FibroScan controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) in the detection of increased arterial stiffness in asymptomatic populations in China.A retrospective cohort recruiting 4747 asymptomatic patients with no underlying causes of liver disease and having FibroScan and brachial-ankle pulse wave velocity (baPWV) during wellness check-up was covered. Nonalcoholic fatty liver disease (NAFLD) was defined as a CAP ≥238 dB/m. NAFLD with significant fibrosis was defined as an LSM ≥7.3 kPa in the presence of NAFLD. Increased arterial stiffness was determined as a BaPWV ≥1.4m/second.Among the 4747 study participants, 1596 subjects (33.6%) suffered from increased arterial stiffness. The prevalence of increased arterial stiffness progressively increased across CAP quartiles and LSM quartiles in NAFLD (23.5%, 30.8%, 38.3%, 43.7%, P < .001 and 33.1%, 36.8%, 40.4%, 48.2%, P < .001, respectively). After conventional cardiovascular risk factors were adjusted (age, sex, overweight, diabetes mellitus, hypertension, hypercholesterolemia, and current smoking habits), multivariate logistic regression analysis revealed that CAP (odd ratio [OR] = 1.005; 95% confidence interval [CI]: 1.003-1.006; P < .001), NAFLD (OR = 1.427; 95% CI: 1.212-1.681; P < .001), LSM in NAFLD (OR = 1.073; 95% CI: 1.023-1.125; P = .003), and significant fibrosis in NAFLD (OR = 1.480; 95% CI: 1.090-2.010; P = .012) were independently associated with increased arterial stiffness. Furthermore, in a multivariate logistic regression analysis, OR (95% CI) for the maximal vs. the minimal quartile of CAP was 1.602 (1.268-2.024), and that of LSM in NAFLD was 1.362 (1.034-1.792) after adjustment for the above-mentioned risk factors. Notably, NAFLD and significant fibrosis in NAFLD were significantly correlated only with increased arterial stiffness in subjects without hypertension or diabetes mellitus after adjustment for the above-mentioned risk factors.CAP-defined NAFLD and LSM-defined significant fibrosis in NAFLD showed significant and independent relationships with increased arterial stiffness even after adjustment for conventional cardiovascular risk factors, which can be conducive to stratifying relative risk of subjects having undergone screening assessment for cardiovascular disease.

A Retrospective Study to Examine the Correlation of Bioelectrical Impedance Analysis with Shear-wave Elastography in Indian Patients with Non-alcoholic Fatty Liver Disease and Diabetes on Background Sodium-glucose Cotransporter-2 Inhibitor Therapy

Background

Patients with non-alcoholic fatty liver disease (NAFLD) are often insulin resistant. Several recent studies show NAFLD to be associated with cardiovascular risk. Bioimpedance analysis (BIA) is a common approach for body composition measurements and is a noninvasive, low-cost modality. Shear-wave elastography (SWE) works using an acoustic radiation force pulse sequence that generates shear-waves that estimates the liver stiffness.

Objectives

The primary objective was to assess the correlation between SWE values and BIA values in an Indian population. The hypothesis is that with the increase in BIA value measuring visceral fat percentage, the SWE value measuring liver stiffness should increase.

Materials and methods

We conducted a retrospective analysis of clinic data of 36 patients properly screened from July 2018 to December 2018, who matched our prespecified inclusion criteria. Statistical analysis was performed using GraphPad Insta Version 3.0^® using regression analysis. Visceral fat percentage and skeletal muscle percentage of lower limbs were calculated using an Omron HBF 375^® analyzer. SWE values for liver fat were measured using a Philips Affinity 70^® using two-dimensional imaging and expressed in kilopascal (kPa) units.

Results

We found that 88.88% of the patients with diabetes had above normal SWE values (2.0 to 4.5 kPa), and a corresponding 83.33% of patients had above the high cut-off for BIA values (>10%) but without any positive correlation between the two parameters as evident from the p-value of 0.079.

Conclusions

This study found a high prevalence of fat burden amongst our patients with type 2 diabetes and NAFLD. This is the first of its kind of study where we searched for a correlation between the two commonly used parameters in assessing the fat burden and liver stiffness of an individual but found there was no significant correlation between the two parameters used.

Automated detection and classification of liver fibrosis stages using contourlet transform and nonlinear features

BACKGROUND AND OBJECTIVE

Liver fibrosis is a type of chronic liver injury that is characterized by an excessive deposition of extracellular matrix protein. Early detection of liver fibrosis may prevent further growth toward liver cirrhosis and hepatocellular carcinoma. In the past, the only method to assess liver fibrosis was through biopsy, but this examination is invasive, expensive, prone to sampling errors, and may cause complications such as bleeding. Ultrasound-based elastography is a promising tool to measure tissue elasticity in real time; however, this technology requires an upgrade of the ultrasound system and software. In this study, a novel computer-aided diagnosis tool is proposed to automatically detect and classify the various stages of liver fibrosis based upon conventional B-mode ultrasound images.

METHODS

The proposed method uses a 2D contourlet transform and a set of texture features that are efficiently extracted from the transformed image. Then, the combination of a kernel discriminant analysis (KDA)-based feature reduction technique and analysis of variance (ANOVA)-based feature ranking technique was used, and the images were then classified into various stages of liver fibrosis.

RESULTS

Our 2D contourlet transform and texture feature analysis approach achieved a 91.46% accuracy using only four features input to the probabilistic neural network classifier, to classify the five stages of liver fibrosis. It also achieved a 92.16% sensitivity and 88.92% specificity for the same model. The evaluation was done on a database of 762 ultrasound images belonging to five different stages of liver fibrosis.

CONCLUSIONS

The findings suggest that the proposed method can be useful to automatically detect and classify liver fibrosis, which would greatly assist clinicians in making an accurate diagnosis.

Rationale, design, and methodology of a trial evaluating three models of care for HCV treatment among injection drug users on opioid agonist therapy

BACKGROUND

People who inject drugs (PWID) constitute 60% of the approximately 5 million people in the U.S. infected with hepatitis C virus (HCV). Treatment of PWID is complex due to addiction, mental illness, poverty, homelessness, lack of positive social support, poor adherence-related skills, low motivation and knowledge, and poor access to and trust in the health care system. New direct-acting antiviral medications are available for HCV with high cure rates and few side effects. The life expectancy and economic benefits of new HCV treatments will not be realized unless we determine optimal models of care for the majority of HCV-infected patients. The purpose of this study is to evaluate the effectiveness of directly observed therapy and group treatment compared with self-administered individual treatment in a large, urban opioid agonist therapy clinic setting in the Bronx, New York.

METHODS/DESIGN

In this randomized controlled trial 150 PWID with chronic HCV were recruited from opioid agonist treatment (OAT) clinics and randomized to one of three models of onsite HCV treatment in OAT: 1) modified directly observed therapy; 2) group treatment; or 3) control - self-administered individual treatment. Participants were age 18 or older, HCV genotype 1, English or Spanish speaking, treatment naïve (or treatment experienced after 12/3/14), willing to receive HCV treatment onsite, receiving methadone or buprenorphine at the medication window at least once per week, and able to provide informed consent. Outcomes of interest include adherence (as measured by self-report and electronic blister packs), HCV treatment completion, sustained virologic response, drug resistance, and cost-effectiveness.

DISCUSSION

This paper describes the design and rationale of a randomized controlled trial comparing three models of care for HCV therapy delivered in an opioid agonist treatment program. Our trial will be critical to rigorously identify models of care that result in high adherence and cure rates. Use of blister pack technology will help us determine the role of adherence in successful cure of HCV. Moreover, the trial methodology outlined here can serve as a template for the development of future programs and studies among HCV-infected drug users receiving opioid agonist therapy, as well as the cost-effectiveness of such programs.

TRIAL REGISTRATION

This trial was registered with ClinicalTrials.gov ( NCT01857245 ). Trial registration was obtained prospectively on May 20th, 2013.

Changes of liver hemodynamic and elastography parameters in patients with colorectal liver metastases receiving preoperative chemotherapy: "a note of caution"

BACKGROUND

New systemic chemotherapy agents have improved prognosis in patients with colorectal liver metastases (CLM), but some of them damage the liver parenchyma and ultimately increase postoperative morbidity and mortality after liver resection. The aims of our study were to determine the degree of hemodynamic and pathological liver injury in CLM patients receiving preoperative chemotherapy and to identify an association between these injuries and postoperative complications after liver resection.

METHODS

This is a prospective descriptive study of patients with CLM receiving preoperative chemotherapy before curative liver resection from November 2013 to June 2014. All patients had preoperative elastography and hepatic hemodynamic evaluation. We analyzed clinical preoperative data and postoperative outcomes after grouping the patients by chemotherapy type, development of sinusoidal obstructive syndrome (SOS), and development of major complications.

RESULTS

Eleven from the 20 patients included in the study received preoperative oxaliplatin-based chemotherapy (OBC). Nine patients had SOS at pathological analysis and five patients developed major complications. Patients receiving preoperative OBC had higher values of hepatic venous pressure gradient (HVPG) and developed more SOS and major complications. Patients developing SOS had higher values of HVPG and developed more major complications. Patients with major complications had higher values of HVPG, and patients with a HVPG of 5 mmHg or greater had more major complications than those under 5 mmHg (20 vs 80%, p = 0.005).

CONCLUSIONS

OBC and SOS impair liver hemodynamics in CLM patients. An increase in major complications after liver resection in these patients develops at subclinical HVPG levels.

Application of Ultrasound Elastography for Chronic Allograft Dysfunction in Kidney Transplantation

Interstitial fibrosis is the main characteristic of chronic allograft dysfunction, which remains the key factor affecting long-term allograft survival after kidney transplantation. Ultrasound elastography (UE), including real-time elastography, transient elastography, and acoustic radiation force impulse, has been applied widely in breast, thyroid, and liver diseases, especially in the assessment of liver fibrosis. Recently, numerous studies have reported the efficacy of UE methods in evaluating renal allograft fibrosis. This review aims to investigate the clinical applications, limitations, and future roles of UE in current clinical practice in light of changing management paradigms. In current clinical practice, UE methods, especially transient elastographic measurement, appear to be useful for ruling out fibrosis but do not have sufficient accuracy to distinguish between various stages of allograft fibrosis. Moreover, there remain considerable issues to be solved for the application of UE in kidney transplantation. Thus, UE methods cannot replace the crucial role of renal allograft biopsy in the diagnosis and evaluation of allograft fibrosis in kidney transplantation. Perhaps UE methods could be of more importance in the long-term observation and evaluation of allograft fibrosis during follow-up.

Evaluation of hepatic fibrosis: a review from the society of abdominal radiology disease focus panel

Hepatic fibrosis is potentially reversible; however early diagnosis is necessary for treatment in order to halt progression to cirrhosis and development of complications including portal hypertension and hepatocellular carcinoma. Morphologic signs of cirrhosis on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) alone are unreliable and are seen with more advanced disease. Newer imaging techniques to diagnose liver fibrosis are reliable and accurate, and include magnetic resonance elastography and US elastography (one-dimensional transient elastography and point shear wave elastography or acoustic radiation force impulse imaging). Research is ongoing with multiple other techniques for the noninvasive diagnosis of hepatic fibrosis, including MRI with diffusion-weighted imaging, hepatobiliary contrast enhancement, and perfusion; CT using perfusion, fractional extracellular space techniques, and dual-energy, contrast-enhanced US, texture analysis in multiple modalities, quantitative mapping, and direct molecular imaging probes. Efforts to advance the noninvasive imaging assessment of hepatic fibrosis will facilitate earlier diagnosis and improve patient monitoring with the goal of preventing the progression to cirrhosis and its complications.

Limitations and artifacts in shear-wave elastography of the liver

Recent studies have shown that real-time, two-dimensional shear-wave elastography (2D-SWE) can monitor liver fibrosis by measuring tissue elasticity (i.e., elastic modulus). Two clinical studies of 2D-SWE in the liver have shown that there are several practical issues that can compromise quantitation of liver tissue elasticity. Both general ultrasound (US) limitations and limitations in the 2D-SWE method itself resulted in significant variability in estimated liver elasticity. The most common US limitations were: poor acoustic window, limited penetration, and rib/lung shadows. The most common 2D-SWE limitations were: reverberations under the liver capsule, respiratory/cardiac motion, and vessel pulsation/loss of SWE signal. Based on these studies, scan protocols have been optimized to minimize the influence of these limitations on liver elasticity quantification. These refined protocols should move non-invasive SWE closer to becoming the preferred tool to diagnose and manage many chronic diseases of the liver.

Ultrasound shear wave elastography and liver fibrosis: A Prospective Multicenter Study

AIM

To assess the accuracy of shear wave elastography (SWE) alone and in combination with aminotransferase platelet ratio index (APRI) score in the staging of liver fibrosis.

METHODS

A multicenter prospective study was conducted to assess the accuracy of SWE (medians) and APRI to predict biopsy results. The analysis focused on distinguishing the different stages of liver disease, namely, F0 from F1-4, F0-1 from F2-4, F0-2 from F3-4 and F0-3 from F4; F0-F1 from F2-F4 being of primary interest. The area under the receiver operating characteristic (AUROC) curve was computed using logistic regression model. The role of age, gender and steatosis was also assessed.

RESULTS

SWE alone accurately distinguished F0-1 from F2-4 with a high probability. The AUROC using SWE alone was 0.91 compared to 0.78 for using the APRI score alone. The APRI score, when used in conjunction with SWE, did not make a significant contribution to the AUROC. SWE and steatosis were the only significant predictors that differentiated F0-1 from F2-4 with an AUROC of 0.944.

CONCLUSION

Our study validates the use of SWE in the diagnosis and staging of liver fibrosis. Furthermore, the probability of a correct diagnosis is significantly enhanced with the addition of steatosis as a prognostic factor.

Efficacy of a 12-Week Simeprevir Plus Peginterferon/Ribavirin (PR) Regimen in Treatment-Naïve Patients with Hepatitis C Virus (HCV) Genotype 4 (GT4) Infection and Mild-To-Moderate Fibrosis Displaying Early On-Treatment Virologic Response

BACKGROUND

HCV GT4 accounts for up to 20% of HCV infections worldwide. Simeprevir, given for 12 weeks as part of a 24- or 48-week combination regimen with PR is approved for the treatment of chronic HCV GT4 infection. Primary study objectives were assessment of efficacy and safety of simeprevir plus PR in treatment-naïve patients with HCV GT4 treated for 12 weeks. Primary efficacy outcome was sustained virologic response 12 weeks post-treatment (SVR12). Additional objectives included investigation of potential associations of rapid virologic response and baseline factors with SVR12.

METHODS

This multicentre, open-label, single-arm study (NCT01846832) evaluated efficacy and safety of simeprevir plus PR in 67 patients with HCV GT4 infection. Patients were treatment-naïve, aged 18-70 years with METAVIR F0-F2 fibrosis. Patients with early virologic response (HCV RNA <25 IU/mL [detectable/undetectable in IL28B CC patients or undetectable in IL28B CT/TT patients] at Week 2 and undetectable at Weeks 4 and 8) were eligible to stop all treatment at the end of Week 12, otherwise PR therapy was continued to Week 24.

RESULTS

Of 67 patients treated, 34 (51%) qualified for 12-week treatment including all but one patient with IL28B CC genotype (14/15). All patients in the 12-week group had undetectable HCV RNA at end of treatment, and 97% (33/34) achieved SVR12. No new safety signals with simeprevir plus PR were identified. The proportion of patients experiencing Grade 3-4 adverse events was lower in the 12-week group than in the 24-week group.

CONCLUSIONS

Our findings on simeprevir plus PR therapy shortened to 12 weeks in patients with HCV GT4 infection with favourable baseline characteristics and displaying early on-treatment virologic response are encouraging. No new safety signals were associated with simeprevir plus PR in this study.

TRIAL REGISTRATION

NCT01846832.

A Meta-analysis for the Diagnostic Performance of Transient Elastography for Clinically Significant Portal Hypertension

We aimed to evaluate the correlation between liver stiffness measurement using transient elastography (TE-LSM) and hepatic venous pressure gradient and the diagnostic performance of TE-LSM in assessing clinically significant portal hypertension through meta-analysis. Eleven studies were included from thorough literature research and selection processes. The summary correlation coefficient was 0.783 (95% confidence interval [CI], 0.737-0.823). Summary sensitivity, specificity and area under the hierarchical summary receiver operating characteristic curve (AUC) were 87.5% (95% CI, 75.8-93.9%), 85.3 % (95% CI, 76.9-90.9%) and 0.9, respectively. The subgroup with low cut-off values of 13.6-18 kPa had better summary estimates (sensitivity 91.2%, specificity 81.3% and partial AUC 0.921) than the subgroup with high cut-off values of 21-25 kPa (sensitivity 71.2%, specificity 90.9% and partial AUC 0.769). In summary, TE-LSM correlated well with hepatic venous pressure gradient and represented good diagnostic performance in diagnosing clinically significant portal hypertension. For use as a sensitive screening tool, we propose using low cut-off values of 13.6-18 kPa in TE-LSM.

Transient elastography as a noninvasive assessment tool for hepatopathies of different etiology in pediatric type 1 diabetes mellitus

AIM

To identify the prevalence and effect of hepatopathies of different etiologies among pediatric patients with type 1 diabetes mellitus (T1DM) using transient elastography (TE) and its relation to glycemic control.

METHODS

One hundred T1DM patients were studied focusing on liver functions, fasting lipid profile, hemoglobin A1c (HbA1c), hepatitis C virus (HCV), serum immunoglobulins, autoimmune antibodies; anti-nuclear antibody (ANA), anti-smooth muscle antibody (ASMA), and anti-liver kidney microsomal antibody (anti-LKM). Abdominal ultrasound was performed and TE was done for patients with HCV, positive autoimmune antibody and/or abnormal ultrasound findings.

RESULTS

Thirty-one patients were found to have one or more hepatic abnormalities; clinical hepatomegaly in 8%, elevated alanine aminotransferase (ALT) in 10%, HCV in 6%, autoimmune hepatitis (AIH) in 11% (10 were positive for ASMA and 2 were positive for ANA while anti-LKM antibodies were negative) and abnormal hepatic ultrasound in 20% (12 non-alcoholic fatty liver disease, 5 AIH, 2 HCV, 1 Mauriac syndrome). Mean liver stiffness in those 31 patients was 7.0±2.1kPa (range, 3.1-11.8kPa); 24 were Metavir F0-F1, 7 were F2-F3 while none was F4. Type 1 diabetic patients with abnormal hepatic ultrasound had higher fasting blood glucose, HbA1c and total cholesterol than those with normal findings. Liver stiffness was significantly higher in patients with abnormal liver ultrasound compared with normal sonography. Liver stiffness was positively correlated to HbA1c and ALT.

CONCLUSIONS

Hepatic abnormalities are prevalent in T1DM and related to poor metabolic control. TE provides a non-invasive method for detection of hepatopathy-induced fibrosis.

Sample, testing and analysis variables affecting liver mechanical properties: A review

Given the critical role of liver mechanics in regulating cell response and directing the development of tissue fibrosis, accurately characterising its mechanical behaviour is of relevance for both diagnostic purposes as well as for tissue engineering and for the development of in-vitro models. Determining and quantifying the mechanical behaviour of soft biological tissues is, however, highly challenging due to their intrinsic labile nature. Indeed, a unique set of values of liver mechanical properties is still lacking to date; testing conditions can significantly affect sample status and hence the measured behaviour and reported results are strongly dependent on the adopted testing method and configuration as well as sample type and status. This review aims at summarising the bulk mechanical properties of liver described in the literature, discussing the possible sources of variation and their implications on the reported results. We distinguish between the intrinsic mechanical behaviour of hepatic tissue, which depends on sample variables, and the measured mechanical properties which also depend on the testing and analysis methods. Finally, the review provides guidelines on tissue preparation and testing conditions for generating reproducible data which can be meaningfully compared across laboratories.

STATEMENT OF SIGNIFICANCE

Soft tissue mechanics is widely investigated, but poorly understood. This review identifies and discusses sample and testing variables which can influence the mechanical behaviour of hepatic tissue and consequently the measured mechanical properties. To encourage the biomaterial community towards more standardized testing of soft tissues and enable comparisons between data from different laboratories, we have established new testing methods and experimental recommendations for sample preparation and testing. The review could be of wide interest to scientists involved in biomaterials research because it addresses and proposes guidelines for several issues related to the mechanical testing of soft tissues whose implications have not been considered together before.

Transient elastography in clinical detection of liver cirrhosis: A systematic review and meta-analysis

BACKGROUND/AIMS

Transient elastography is a noninvasive method for measuring liver fibrosis. This meta-analysis assesses the diagnostic performance of transient elastography of detecting liver cirrhosis in patients with liver disease.

PATIENTS AND METHODS

We searched MEDLINE, Cochrane, EMBASE databases until Jan 31, 2015, using the following search terms: elastography and liver cirrhosis. Included studies assessed patients with a diagnosis of liver cirrhosis, with an index test of transient elastography, and with the reference standard being a histopathological exam by liver biopsy. Sensitivity analysis and assessment of risk of bias and publication bias were performed.

RESULTS

Fifty-seven studies were included in the meta-analysis with a total of 10,504 patients. The pooled estimate for the sensitivity of transient elastography for detecting liver fibrosis was 81% and the specificity was 88%. The imputed diagnostic odds ratio (DOR) was 26.08 and the area under the receiver-operating characteristic (AUROC) curve was 0.931.

CONCLUSION

Our findings indicate that transient elastography shows good sensitivity, specificity and a high accuracy for detecting liver cirrhosis. Transient elastography can be used as an additional method for the clinical diagnosis of liver fibrosis and cirrhosis.

Non-invasive assessment of liver fibrosis: Between prediction/prevention of outcomes and cost-effectiveness

The assessment of the fibrotic evolution of chronic hepatitis has always been a challenge for the clinical hepatologist. Over the past decade, various non-invasive methods have been proposed to detect the presence of fibrosis, including the elastometric measure of stiffness, panels of clinical and biochemical parameters, and combinations of both methods. The aim of this review is to analyse the most recent data on non-invasive techniques for the evaluation of hepatic fibrosis with particular attention to cost-effectiveness. We searched for relevant studies published in English using the PubMed database from 2009 to the present. A large number of studies have suggested that elastography and serum markers are useful techniques for diagnosing severe fibrosis and cirrhosis and for excluding significant fibrosis in hepatitis C virus patients. In addition, hepatic stiffness may also help to prognosticate treatment response to antiviral therapy. It has also been shown that magnetic resonance elastography has a high accuracy for staging and differentiating liver fibrosis. Finally, studies have shown that non-invasive methods are becoming increasingly precise in either positively identifying or excluding liver fibrosis, thus reducing the need for liver biopsy. However, both serum markers and transient elastography still have “grey area” values of lower accuracy. In this case, liver biopsy is still required to properly assess liver fibrosis. Recently, the guidelines produced by the World Health Organization have suggested that the AST-to-platelet ratio index or FIB-4 test could be utilised for the evaluation of liver fibrosis rather than other, more expensive non-invasive tests, such as elastography or FibroTest.

Non-invasive assessment of liver fibrosis in patients with alcoholic liver disease using acoustic radiation force impulse elastography

OBJECTIVES

To investigate the diagnostic performance of the acoustic radiation force impulse (ARFI) elastography for the assessment of the liver fibrosis in alcoholic liver disease (ALD).

METHODS

We included 112 patients with ALD in whom liver biopsy, ARFI elastography, and aspartate-to-platelet ratio index (APRI) measurements were performed.

RESULTS

ARFI elastography correlated significantly with histological fibrosis (r = 0.685, P < 0.001) in patients with ALD. The diagnostic accuracies expressed as areas under receiver operating characteristic (AUROC) curves for ARFI elastography and APRI were 0.846 and 0.763 for the diagnosis of significant fibrosis (S ≥ 2), 0.875 and 0.688 for the diagnosis of severe fibrosis (S ≥ 3), and 0.893 and 0.648 for the diagnosis of liver cirrhosis, respectively. The AUROC values of ARFI elastography were significantly better than those of APRI for predicting severe fibrosis (P = 0.02) and cirrhosis (P = 0.04). The optimum cutoff values for ARFI elastography were 1.33 m/s for S ≥ 2, 1.40 m/s for S ≥ 3, and 1.65 m/s for S = 4 in patients with elevated alanine aminotransferase (ALT) levels; these decreased to 1.24 m/s for S ≥ 2, 1.27 m/s for S ≥ 3, and 1.41 m/s for S = 4 in patients with normal ALT.

CONCLUSION

ARFI elastography is an acceptable method for predicting the severity of fibrosis in patients with ALD. ARFI elastography is influenced by elevated aminotransferase levels in ALD.

Liver stiffness and portal blood flow modifications induced by a liquid meal consumption: pathogenetic mechanisms and clinical relevance

OBJECTIVE

The correlation between liver stiffness (LS) variations and portal blood flow (PBF) modifications induced by a standardized liquid meal consumption and the clinical relevance of this matter are two aspects not yet fully elucidated. Herein, we evaluated the variations of LS and PBF after a standardized liquid meal intake in patients with chronic liver disease.

MATERIAL AND METHODS

PBF and LS were determined after an overnight fasting period in 54 patients. They were divided in three groups according to baseline LS (absent, moderate, and severe). They consumed 200 ml of water and a standardized liquid meal (300 Kcal/200 ml) after 60 min. PBF and LS were measured at 30 min after water and liquid meal consumption.

RESULTS

In all groups, LS and PBF values significantly increased only after meal consumption. A significant correlation between baseline LS values and post-meal increase of LS was observed. Moreover, higher basal stiffness values were associated to a larger increase of LS variation after meal consumption. The effect of the meal on LS remained statistically significant after multiple regression analysis. A significant correlation between increase of LS and PBF was found in patients with absent and moderate baseline LS. Nine patients (17%) switched from a lower to a higher level of LS after meal consumption.

CONCLUSION

A low calories/low-volume meal is capable of significantly increasing LS regardless of the grade of stiffness, determining a reclassification rate of 17%. In presence of minimal or moderate stiffness, the increase of LS is significantly correlated with the augment of PBF.

The frequency and determinants of liver stiffness measurement failure: a retrospective study of "real-life" 38,464 examinations

Objective

To investigate the frequency and determinants of liver stiffness measurement (LSM) failure by means of FibroScan in “real-life” Chinese patients.

Methods

A total of 38,464 “real-life” Chinese patients in 302 military hospital of China through the whole year of 2013, including asymptomatic carrier, chronic hepatitis B, chronic hepatitis C, liver cirrhosis (LC), alcoholic liver disease, autoimmune liver disease, hepatocellular carcinoma (HCC) and other, were enrolled, their clinical and biological parameters were retrospectively investigated. Liver fibrosis was evaluated by FibroScan detection. S probe (for children with height less than 1.20 m) and M probe (for adults) were used. LSM failure defined as zero valid shots (unsuccessful LSM), or the ratio of the interquartile range to the median of 10 measurements (IQR/M) greater than 0.30 plus median LSM greater or equal to 7.1 kPa (unreliable LSM).

Results

LSM failure occurred in 3.34% of all examinations (1286 patients out of 38,464), among them, there were 958 cases (2.49%) with unsuccessful LSM, and 328 patients (0.85%) with unreliable LSM. Statistical analyses showed that LSM failure was independently associated with body mass index (BMI) greater than 30 kg/m², female sex, age greater than 50 years, intercostal spaces (IS) less than 9 mm, decompensated liver cirrhosis and HCC patients. There were no significant differences among other diseases. By changing another skilled operator, success was achieved on 301 cases out of 1286, which reduced the failure rate to 2.56%, the decrease was significant (P<0.0001).

Conclusions

The principal reasons of LSM failure are ascites, obesity and narrow of IS. The failure rates of HCC, decompensated LC, elder or female patients are higher. These results emphasize the need for adequate operator training, technological improvements and optimal criteria for specific patient subpopulations.

Re-appraisal of old and new diagnostic tools in the current management of chronic hepatitis B

Hepatitis B virus (HBV) is a very complex and intricate DNA structure associated with a particular genomic organization and replication cycle. However, many years of investigations allowed clarification of the real HBV natural history, through a deeper knowledge of the behavior of HBV antigens and viral structures. Several of the old diagnostic tools, such as HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) determinations, gained prominence now, since the variation of both HBsAg and HBeAg plasma levels was shown to predict treatment response. In addition, the availability of more sensitive methods, such as HBV DNA detection by real-time PCR, has improved the current knowledge of the relationships between HBV replication levels and the natural history of the disease. It is now well established that some HBV genotypes are associated with a better response to treatment with pegylated interferon. Despite the widely accepted value of liver biopsy as a staging tool, transient elastography is being increasingly acknowledged as a non-invasive method to assess liver stiffness, chiefly for detection of advanced fibrosis. Current international guidelines for the management of chronic hepatitis B have provided several accurate biochemical and serological criteria for selecting patients for treatment, allowing a higher number of cases to be enrolled into antiviral therapy. This review describes the different serological markers used for the study of HBV and their clinical significance. It also deals with methods used for detection of genotypes and HBV DNA, emphasizing the effectiveness of such determinations for both patient selection and chronic hepatitis B therapy/monitoring.

Chronic hepatitis B virus in young adults: the need for new approaches to management

One in four patients infected with hepatitis B virus (HBV) at birth or in early childhood will develop cirrhosis or hepatocellular carcinoma. Historically, guidelines have overlooked treatment in young people, as the immune tolerant disease phase is considered synonymous with chronic infection in the young. Current treatment aims to suppress HBV replication through long-term nucleos(t)ide therapy with little emphasis on virus eradication. To achieve HBsAg loss, it is accepted that effective immune control of virus is required, mimicking that seen in those who resolve acute HBV infection. We have recently challenged the accuracy of a generic immune tolerant state in young people, thus raising a potential role for earlier treatment. Here we report on our immunological analysis of HBV in young people and the role of a dedicated clinic; we make the case for earlier intervention to achieve effective immune control leading to better outcomes.

Controlled attenuation parameter for evaluating liver steatosis in chronic viral hepatitis

AIM: To assess the performance of controlled attenuation parameter (CAP) in patients with chronic viral hepatitis.

METHODS: CAP is a new technique that measures the attenuation in the liver of an ultrasound beam, which is directly related to lipid accumulation. Consecutive patients undergoing liver biopsy for chronic viral hepatitis were studied using the M probe of FibroScan device (Echosens, Paris, France). The device estimates liver steatosis in decibel per meter (dB/m). An expert operator performed all measurements. Steatosis was graded according to Kleiner’s classification. Pearson or Spearman rank coefficient was used to test correlation between two study variables. Linear regression was used for multivariate model to assess the association between CAP and other variables. Receiver operating characteristic curve analysis was performed to calculate area under the curve (AUROC) for S0 vs S1-S3 and S0-S1 vs S2-S3.

RESULTS: 115 subjects (85 males and 30 females) were prospectively studied. The mean values of CAP were 227.1 ± 43.1 for S0; 254.6 ± 38.9 for S1; 297.8 ± 49.4 dB/m for S2-S3. In univariate analysis CAP showed a significant correlation with age, body mass index (BMI), degree of steatosis, and cholesterol. Multivariate regression analysis confirmed the correlation with the degree of steatosis [coefficient, 1.2 (0.60-1.83); P < 10^-5] and BMI [coefficient, 4.1 (0.5-7.8); P = 0.03] but not with all other variables. Optimal cutoff values for S ≥ 1 and S ≥ 2 were 219 dB/m [AUROC, 0.76 (0.67-0.84); sensitivity, 91.1% (78.8-97.5); specificity, 51.6% (38.7-64.2); positive predictive value, 56.9% (44.7-68.6); negative predictive value, 89.2% (74.3-97.0); positive likelihood ratio, 1.88 (1.4-2.5); negative likelihood ratio, 0.17 (0.07-0.5)] and 296 dB/m [AUROC, 0.82 (0.74-0.89); sensitivity, 60.0% (32.3-83.7); specificity, 91.5% (83.9-96.3); positive predictive value, 52.9% (27.8-77.0); negative predictive value, 93.5% (86.3-97.6); positive likelihood ratio, 7.05 (3.2-15.4); negative likelihood ratio, 0.44 (0.2-0.8)], respectively.

CONCLUSION: Controlled attenuation parameter could be a useful tool in the clinical management of patients with chronic viral hepatitis for detecting liver steatosis.

Clinical Application of Transient Elastography in the Diagnosis of Liver Fibrosis: an Expert Panel Review and Opinion

Liver fibrosis evaluation is pivotal for treatment decisions and prognosis assessment in patients with chronic liver disease. Liver transient elastography (TE) is a newly developed non-invasive technique for diagnosis of liver fibrosis. It can assess the state of liver fibrosis by liver stiffness measurements, and offers better performance for the diagnosis of liver cirrhosis than serum biological markers. It has now been approved for clinical use in China. The aim of this review is to provide a guide for clinicians to apply this technique appropriately. The recommendations are made under the auspices of China Foundation for Hepatitis Prevention and Control, and have been prepared by a panel experts, who have reviewed and summarized the clinical studies on TE in order to develop these recommendations.

Point shear wave elastography method for assessing liver stiffness

AIM: To estimate the validity of the point shear-wave elastography method by evaluating its reproducibility and accuracy for assessing liver stiffness.

METHODS: This was a single-center, cross-sectional study. Consecutive patients with chronic viral hepatitis scheduled for liver biopsy (LB) (Group 1) and healthy volunteers (Group 2) were studied. In each subject 10 consecutive point shear-wave elastography (PSWE) measurements were performed using the iU22 ultrasound system (Philips Medical Systems, Bothell, WA, United States). Patients in Group 1 underwent PSWE, transient elastography (TE) using FibroScan (Echosens, Paris, France) and ultrasound-assisted LB. For the assessment of PSWE reproducibility two expert raters (rater 1 and rater 2) independently performed the examinations. The performance of PSWE was compared to that of TE using LB as a reference standard. Fibrosis was staged according to the METAVIR scoring system. Receiver operating characteristic curve analyses were performed to calculate the area under the receiver operating characteristic curve (AUC) for F≥ 2, F≥ 3 and F = 4. The intraobserver and interobserver reproducibility of PSWE were assessed by calculating Lin’s concordance correlation coefficient.

RESULTS: To assess the performance of PSWE, 134 consecutive patients in Group 1 were studied. The median values of PSWE and TE (in kilopascals) were 4.7 (IQR = 3.8-5.4) and 5.5 (IQR = 4.7-6.5), respectively, in patients at the F0-F1 stage and 3.5 (IQR = 3.2-4.0) and 4.4 (IQR = 3.5-4.9), respectively, in the healthy volunteers in Group 2 (P < 10^-5). In the univariate analysis, the PSWE and TE values showed a high correlation with the fibrosis stage; low correlations with the degree of necroinflammation, aspartate aminotransferase and gamma-glutamyl transferase (GGT); and a moderate negative correlation with the platelet count. A multiple regression analysis confirmed the correlations of both PSWE and TE with fibrosis stage and GGT but not with any other variables. The following AUC values were found: 0.80 (0.71-0.87) for PSWE and 0.82 (0.73-0.89) for TE (P = 0.42); 0.88 (0.80-0.94) for PSWE and 0.95 (0.88-0.98) for TE (P = 0.06); and 0.95 (0.89-0.99) for PSWE and 0.92 (0.85-0.97) for TE (P = 0.30) for F≥ 2, F≥ 3 and F = 4, respectively. To assess PSWE reproducibility, 116 subjects were studied, including 47 consecutive patients scheduled for LB (Group 1) and 69 consecutive healthy volunteers (Group 2). The intraobserver agreement ranged from 0.83 (95%CI: 0.79-0.88) to 0.96 (95%CI: 0.95-0.97) for rater 1 and from 0.84 (95%CI: 0.79-0.88) to 0.96 (95%CI: 0.95-0.97) for rater 2. The interobserver agreement yielded values from 0.83 (95%CI: 0.78-0.88) to 0.93 (95%CI: 0.91-0.95).

CONCLUSION: PSWE is a reproducible method for assessing liver stiffness, and it compares with TE. Compared with patients with nonsignificant fibrosis, healthy volunteers showed significantly lower values.

Liver stiffness measured by transient elastography in patients with acute pancreatitis

BACKGROUND

Alcohol abuse constitutes a risk factor for acute pancreatitis and liver cirrhosis, and cirrhosis in turn may delay the recovery from pancreatitis. We evaluated the occurrence and significance of liver fibrosis or cirrhosis in patients with acute pancreatitis by applying transient elastography (TE).

METHODS

TE was carried out in 78 patients with acute pancreatitis. Comparisons were made to the severity and recurrence of pancreatitis, to biological markers for fibrosis (APRI test), alcohol intake (AST/ALT ratio, AUDIT), and prothrombin time (TT-SPA). A cut-off value of ≥7.5 kilopascals (kPa) was set for increased liver stiffness, and ≥10 kPa for significant fibrosis.

RESULTS

The aetiology of pancreatitis was alcohol intake in 62 patients, gallstones in 11, idiopathic in 3, tumour in 1 and medication in 1. TE was successful in 64 out of 78 patients. The median TE value was 6.5 kPa (range 2.5-61.1); 22 (35%) had values ≥7.5 kPa and 7 (11%) ≥10 kPa. Values ≥7.5 were associated with older age, higher APRI ratio, and lower TT-SPA. It did not predict the length of hospitalization or the recurrence of pancreatitis. Increased AST/ALT ratio was associated with high TE values, whereas AUDIT values were not. Values ≥10 kPa seemed to indicate manifest cirrhosis, hepatitis or subsequent development of diabetes.

CONCLUSIONS

TE values ≥7.5 kPa did not predict the length of hospital stay or recurrence of pancreatitis but there were some findings of impaired liver function. Values ≥10 kPa may indicate subsequent development of diabetes and a more severe course of acute pancreatitis.

Shear wave elastography for evaluation of liver fibrosis

The prognosis and management of chronic viral hepatitis mainly depend on the extent of liver fibrosis, particularly in chronic hepatitis C. Liver histologic analysis is still considered the reference standard in the assessment of liver fibrosis despite the interobserver and interobserver variability in staging and some morbidity and mortality risks. Thus, noninvasive methods for assessing liver fibrosis are of great clinical interest. In the last decade, ultrasound-based techniques to estimate the stage of liver fibrosis have become commercially available. They all have the capability to noninvasively evaluate differences in the elastic properties of soft tissues by measuring tissue behavior when a mechanical stress is applied. Shear wave elastography relies on the generation of shear waves determined by the displacement of tissues induced by the force of a focused ultrasound beam or by an external push. This article reviews the results that have been obtained with shear wave elastography for assessment of liver fibrosis.

Evaluation of hepatic fibrosis stage (≥ F2) by fibroscan in patients with chronic viral hepatitis: A Meta-analysis

AIM: To evaluate the value of fibroscan (FS) in hepatic fibrosis stage assessment in patients with chronic viral hepatitis, and to examine whether its accuracy is affected by etiology.

METHODS: English and Chinese articles related to assessment of hepatic fibrosis stage by fibroscan in Wanfang, Chinese Journal Full-Text Database (CJFD), Chinese Biomedical Literature Database (CBM), PubMed, Cochrane library and EMBASE database were strictly screened and evaluated. Data of enrolled articles were analyzed using Meta-disc1.4 and Stata12.0 software.

RESULTS: A total of 28 English and Chinese articles were included. The pooled sensitivity, specificity, diagnostic odds ratio and the area under curve (AUC) of summary receiver operating characteristic (SROC) curve for significant fibrosis (F ≥ 2) and cirrhosis (F = 4) in patients with chronic viral hepatitis were 0.72 (0.70-0.73), 0.85 (0.83-0.87), 18.51 (13.28-25.80), 0.88 and 0.86 (0.84-0.88), 0.86 (0.85-0.87), 49.14 (30.53-79.09) and 0.94, respectively. There was no significant difference among the results of meta-analysis according to etiology.

CONCLUSION: Fibroscan has a high diagnostic accuracy for evaluating hepatic fibrosis stage, especially in patients with cirrhosis. The diagnostic accuracy of fibroscan is not affected by etiology.

Liver elastography, comments on EFSUMB elastography guidelines 2013

Recently the European Federation of Societies for Ultrasound in Medicine and Biology Guidelines and Recommendations have been published assessing the clinical use of ultrasound elastography. The document is intended to form a reference and to guide clinical users in a practical way. They give practical advice for the use and interpretation. Liver disease forms the largest section, reflecting published experience to date including evidence from meta-analyses with shear wave and strain elastography. In this review comments and illustrations on the guidelines are given.