Elastography for the diagnosis of severity of fibrosis in chronic liver disease: a meta-analysis of diagnostic accuracy

Diagnostic Accuracy of SuperSonic Shear Imaging for Staging of Liver Fibrosis: A Meta-analysis

OBJECTIVES

The purpose of this study was to assess the performance of SuperSonic shear imaging (SuperSonic Imagine SA, Aix-en-Provence, France) for diagnosis of liver fibrosis.

METHODS

Literature databases were searched to identify relevant studies from inception to February 28, 2015. Sensitivity, specificity, and other information were extracted from the studies. Pooled data were calculated by a bivariate mixed-effects binary regression model. Subgroup and sensitivity analyses were performed. Publication bias was tested by funnel plots.

RESULTS

Twelve studies were included in this meta-analysis and reported on 1635 patients. The pooled sensitivity and specificity were 0.78 (95% confidence interval [CI], 0.69-0.85) and 0.95 (95% CI, 0.75-0.99), respectively, for fibrosis stages F≥1, 0.84 (95% CI, 0.81-0.86) and 0.81 (95% CI, 0.74-0.87) for F≥2, 0.89 (95% CI, 0.85-0.93) and 0.84 (95% CI, 0.77-0.89) for F≥3, and 0.88 (95% CI, 0.82-0.91) and 0.86 (95% CI, 0.81-0.90) for F=4. The areas under the summary receiver operating characteristic curves were 0.87 (95% CI, 0.84-0.90) for F≥1, 0.85 (95% CI, 0.81-0.88) for F≥2, 0.93 (95% CI, 0.91-0.95) for F≥3, and 0.93 (95% CI, 0.90-0.95) for F=4. No significant publication bias was found.

CONCLUSIONS

SuperSonic shear imaging could be used for staging of liver fibrosis. Especially, it has high diagnostic accuracy for severe fibrosis and cirrhosis.

Systematic review with meta-analysis: the diagnostic accuracy of transient elastography for the staging of liver fibrosis in patients with chronic hepatitis B

BACKGROUND

Transient elastography is a non-invasive method for staging liver fibrosis. The meta-analysis using the hierarchical models to evaluate the diagnostic accuracy of transient elastography for the staging of liver fibrosis in patients with chronic hepatitis B was rarely reported.

AIM

A meta-analysis using the hierarchical models was performed to assess transient elastography for diagnosing and stage liver fibrosis in patients with chronic hepatitis B.

METHODS

Electronic databases were searched and studies were identified to assess the diagnostic accuracy of transient elastography in CHB patients for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 with liver biopsy as a reference standard. The hierarchical summary receiver operating characteristic curve and the bivariate models were performed to evaluate the diagnostic accuracy of transient elastography, and meta-regression analyses were performed to explore the heterogeneity. The quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess the quality of studies.

RESULTS

Twenty-seven studies with a total of 4386 patients were included in the meta-analysis. The summary sensitivity of transient elastography for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 was 0.806 (95% CI, 0.756-0.847), 0.819 (95% CI, 0.748-0.874) and 0.863 (95% CI, 0.818-0.898), respectively, and the summary specificity was 0.824 (95% CI, 0.761-0.873), 0.866 (95% CI, 0.824-0.899) and 0.875 (95% CI, 0.840-0.903), respectively. The corresponding area under the summary receiver operating characteristic curve was 0.88 (95% CI, 0.85-0.91), 0.91 (95% CI, 0.88-0.93) and 0.93 (95% CI, 0.91-0.95), respectively. Meta-regression showed that patient age contributed to heterogeneity.

CONCLUSIONS

Transient elastography performs well to diagnose liver fibrosis in patients with chronic hepatitis B, which may reduce the use of liver biopsy.

Non-invasive assessment of liver fibrosis using acoustic structure quantification: comparison with transient elastography in chronic viral hepatitis

PURPOSE

The purpose of this study was to evaluate the diagnostic efficacy of acoustic structure quantification (ASQ) parameters [mode, average, and focal distribution (FD) ratio] in the staging of hepatic fibrosis in patients with chronic viral hepatitis and to compare it with transient elastography (TE) by using liver biopsy as reference standard.

METHODS

We studied 62 patients with chronic viral hepatitis. Each patient underwent ASQ evaluation and liver biopsy; 54 of these patients received TE. Thirty-six participants without any liver disease were enrolled as normal group, who also underwent ASQ evaluation and TE. All three parameters of ASQ were compared with the histologic fibrosis grade according to the METAVIR scoring (F0-F4). Statistical analysis was performed to investigate the correlations and the diagnostic values of ASQ parameters and compare them to TE.

RESULTS

All three ASQ parameters and TE were significantly correlated with liver fibrosis stage. Of the ASQ parameters, the mode parameter showed the best correlation (P < 0.001). On the area under the receiver operating characteristic curve (AUROC), the mode parameter of ASQ analysis showed both significant correlation and good accuracy for diagnosis of F ≥ 1, F ≥ 2, and F ≥ 3. These values were significantly better than those of the average and FD ratio parameters in F ≥ 1 and F ≥ 2 (P < 0.05). There was no statistically significant difference in AUROC between the mode parameter and TE in diagnosis of F ≥ 1, F ≥ 2, or F ≥ 3.

CONCLUSIONS

The mode parameter is the most reliable ASQ parameter, comparable to TE, as a non-invasive method for the detection and grading of liver fibrosis in patients with chronic viral hepatitis.

Cost-effectiveness of noninvasive liver fibrosis tests for treatment decisions in patients with chronic hepatitis B in the UK: systematic review and economic evaluation

We compared the cost-effectiveness of various noninvasive tests (NITs) in patients with chronic hepatitis B and elevated transaminases and/or viral load who would normally undergo liver biopsy to inform treatment decisions. We searched various databases until April 2012. We conducted a systematic review and meta-analysis to calculate the diagnostic accuracy of various NITs using a bivariate random-effects model. We constructed a probabilistic decision analytical model to estimate health care costs and outcomes quality-adjusted-life-years (QALYs) using data from the meta-analysis, literature, and national UK data. We compared the cost-effectiveness of four decision-making strategies: testing with NITs and treating patients with fibrosis stage ≥F2, testing with liver biopsy and treating patients with ≥F2, treat none (watchful waiting) and treat all irrespective of fibrosis. Treating all patients without prior fibrosis assessment had an incremental cost-effectiveness ratio (ICER) of £28,137 per additional QALY gained for HBeAg-negative patients. For HBeAg-positive patients, using Fibroscan was the most cost-effective option with an ICER of £23,345. The base case results remained robust in the majority of sensitivity analyses, but were sensitive to changes in the ≥ F2 prevalence and the benefit of treatment in patients with F0-F1. For HBeAg-negative patients, strategies excluding NITs were the most cost-effective: treating all patients regardless of fibrosis level if the high cost-effectiveness threshold of £30,000 is accepted; watchful waiting if not. For HBeAg-positive patients, using Fibroscan to identify and treat those with ≥F2 was the most cost-effective option.

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.

Effect of Pressure on Liver Stiffness During the Development of Liver Fibrosis in Rabbits

This study was designed to investigate whether hepatic arterial pressure and portal pressure have an effect on liver stiffness during the development of liver fibrosis. Liver fibrosis was induced in 50 healthy New Zealand white rabbits. Laparotomy was performed to measure liver stiffness, and the portal vein and hepatic artery were successively ligated to repeat the measurements. A significant difference was observed among liver stiffness values measured at different time points (F = 22.82, p < 0.001). Differences between original liver stiffness and liver stiffness measured after portal ligation were positively correlated with portal pressure (r = 0.801, p < 0.001). In animals with grade 4 liver fibrosis, the increase in liver stiffness caused by pressure was greater than that caused by extracellular matrix accumulation (p = 0.002). In conclusion, hepatic arterial pressure and portal pressure have a significant effect on liver stiffness during the development of liver fibrosis.

Acoustic radiation force impulse quantification of spleen elasticity for assessing liver fibrosis

PURPOSE

The purpose of this study is to assess the correlation between liver fibrosis and spleen stiffness measured by ARFI in patients with chronic viral hepatitis (B or C) and to explore the possible complementary role of spleen and liver ARFI in grading liver fibrosis.

METHODS

84 subjects (51 patients, 33 healthy volunteers) were enrolled. ARFI of the spleen and the liver was performed. Patients subsequently underwent liver biopsy for grading liver fibrosis according to Knodell scoring system. Multivariate logistic regression and decision tree analysis were adopted to test the relationship between spleen and liver stiffness (independent variables) and liver fibrosis (F1< vs. ≥F3). Leave-One-Out Cross-Validation was used for validating the predictive classification models. Area under the ROC curve (AUROCC) was used as accuracy metric.

RESULTS

Spleen ARFI was able to discriminate early (F1) from severe (≥F3) liver fibrosis with an optimal cut-off of 3.05 m/s: AUROCC 0.807, cross-validated AUROCC 0.614. Liver ARFI was superior to spleen ARFI, using a cut-off of 2.11 m/s: AUROCC 0.879, cross-validated AUROCC 0.672. Neither spleen nor liver ARFI was able to differentiate healthy volunteers from F1 patients. Odds ratios derived from logistic regression were 23.1 and 9.9 for liver and spleen ARFI, respectively; resulting AUROCC was 0.905 (cross-validated 0.848). A decision tree considering the sequential use of liver and spleen ARFI with cut-off of 2.14 and 3.39 m/s, respectively, resulted in AUROCC of 0.903 (cross-validated 0.7).

CONCLUSIONS

Spleen ARFI has the potential to discriminate early from severe liver fibrosis. Spleen and liver ARFI, when combined, show a better discriminative power than liver ARFI alone.

Magnetic resonance elastography and acoustic radiation force impulse for staging hepatic fibrosis: a meta-analysis

PURPOSE

Elastography is a non-invasive method to quantify fibrosis based on tissue mechanical properties. We performed a meta-analysis to assess the diagnostic accuracy of two such techniques: Acoustic Radiation Force Impulse Imaging (ARFI) or Magnetic Resonance Elastography (MRE) for staging hepatic fibrosis.

MATERIALS AND METHODS

Literature databases were searched until June 2013. Inclusion criteria were evaluation of MRE or ARFI, liver biopsy, and reported sensitivity and specificity. A random effects model was used to combine sensitivity and specificity, from which positive (LR+) and negative (LR-) likelihood ratios, diagnostic odds ratios, and area under receiver operating characteristics curve (AUROC) were derived. Differences between MRE and ARFI were compared with t tests (P < 0.05 considered significant).

RESULTS

Eleven MRE studies including 982 patients and fifteen ARFI studies including 2,128 patients were selected. AUROC for MRE staging fibrosis were 0.94, 0.97, 0.96, and 0.97 for F1-F4, respectively, whereas AUROC for ARFI staging were 0.82, 0.85, 0.94, and 0.94 for F1-F4, respectively. Significance was found in AUROC between MRE and ARFI for the diagnosis of stage 1 and 2 fibrosis.

CONCLUSION

MRE is more accurate than ARFI with a higher combination of sensitivity, specificity, LR, and AUROC particularly in diagnosing early stages of hepatic fibrosis.

Liver and spleen transient elastography predicts portal hypertension in patients with chronic liver disease: a prospective cohort study

BACKGROUND

To assess correlation between liver or spleen stiffness measurement by transient elastography (TE) and hepatic venous pressure gradient (HVPG) in patients with chronic liver disease as well find optimal and rule in/rule out cut-offs for prognosis of clinically significant (CSPH) and severe (SPH) portal hypertension.

METHODS

In this prospective study patients with different chronic liver diseases were included. TE was performed at the same day prior to HVPG measurement. HVPG was measured using catheter tip occlusion technique. Based on HVPG, patients were categorized into groups of CSPH and SPH. Cut-off values were established by applying ROC curve analysis.

RESULTS

The study included 107 consecutive patients referred for HVPG measurement or transjugular liver biopsy. Successful spleen TE was performed in 99 of the patients. Liver and spleen TE strongly correlated with HVPG, r = 0.75 and r = 0.62, respectively. Accuracy to detect CSPH was 88.7% for liver stiffness of 17.4 kPa and 77.7% for spleen stiffness of 47.6 kPa. Accuracy to detect SPH was 83.1% for liver stiffness of 20.6 kPa and 77.7 % for spleen stiffness of 50.7 kPa. Liver stiffness <11.4 kPa could rule out CSPH with 55.2% specificity and >21.9 kPa rule in CSPH with 74.4% sensitivity. Liver stiffness <12.1 kPa could rule out SPH with 50.0% specificity and >35 kPa rule in SPH with 58.2% sensitivity.

CONCLUSIONS

Liver and spleen stiffness correlate with HVPG and could be used to predict CSPH or SPH. Spleen elastography was not superior to liver elastography in predicting portal hypertension.

Non invasive assessment of liver fibrosis in chronic hemodialysis patients with viral hepatitis C

The liver biopsy has long been the "gold standard" for assessing liver fibrosis in patients with hepatitis C. It's an invasive procedure which is associated with an elevated bleeding, especially in chronic hemodialysis patients. Main goal is to assess liver fibrosis in chronic hemodialysis with HCV by Fibroscan and by biological scores (APRI, Forns and Fib-4), and to measure the correlation between these tests. Cross-sectional study including all chronic hemodialysis patients with hepatitis C virus, in two public hemodialysis centers of Fez. All patients were evaluated for liver fibrosis using noninvasive methods (FibroScan and laboratory tests). Subsequently, the correlation between different tests has been measured. 95 chronic hemodialysis were studied, twenty nine patients (30.5%) with chronic hepatitis C. The average age was 52.38 ± 16.8 years. Nine liver fibrosis cases have been concluded by forns score. Fibroscan has objectified significant fibrosis in 6 cases. On the other side APRI has objectified sgnifivant fibrosis only in 3 cases. The Fib-4 showed severe fibrosis in five cases. The results have been most consistent between APRI and Fib-4, followed by Fibroscan and Forns, then APRI and FibroScan.

The Impact of PNPLA3 rs738409 SNP on Liver Fibrosis Progression, Portal Hypertension and Hepatic Steatosis in HIV/HCV Coinfection

BACKGROUND

Faster fibrosis progression and hepatic steatosis are hallmarks of HIV/HCV coinfection. A single nucleotide polymorphism (SNP) of the PNPLA3-gene is associated with development of non-alcoholic steatohepatitis and a worse outcome in alcoholic liver disease. However, the role of PNPLA3 rs738409 SNP on liver fibrosis and steatosis, portal hypertension, and virological response in HIV/HCV coinfection remains unclear.

METHODS

In this cross-sectional study PNPLA3 (rs738409) and IL28B (rs12979860) SNPs were determined in 177 HIV/HCV coinfected patients. Liver fibrosis and steatosis-staged by liver biopsy and transient elastography using the Controlled Attenuation Parameter (CAP)-and portal hypertension (hepatic venous pressure gradient, HVPG) were compared across PNPLA3 genotypes.

RESULTS

75 (42.4%) patients tested positive for a PNPLA3 minor/major risk allele (G/C:66; G/G:9) showed comparable fibrosis stages (median F2 vs. F2; p = 0.292) and similar amounts of hepatic steatosis (CAP: 203.5 ± 41.9 vs. 215.5 ± 59.7 dB/m; p = 0.563) as compared to patients without a PNPLA3 risk allele. Advanced liver fibrosis was neither associated with PNPLA3 (p = 0.253) nor IL28B-genotype (p = 0.628), but with HCV-GT3 (p = 0.003), higher BMI (p = 0.008) and higher age (p = 0.007). Fibrosis progression rate (0.27 ± 0.41 vs. 0.20 ± 0.26 units/year; p = 0.984) and HVPG (3.9 ± 2.6 vs. 4.4 ± 3.0 mmHg; p = 0.472) were similar in patients with and without PNPLA3 risk alleles. SVR rates to PEGIFN/RBV therapy were similar across PNPLA3 genotypes.

CONCLUSIONS

The presence of a PNPLA3 risk allele had no independent impact on liver disease or virological response rates to PEGIFN/RBV therapy in our cohort of HIV/HCV coinfected patients.

Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation

BACKGROUND

Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established.

OBJECTIVE

To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease.

DATA SOURCES

We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists.

METHODS

We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted.

RESULTS

Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822.

LIMITATIONS

A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments.

CONCLUSIONS

Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Noninvasive assessment of alcoholic liver disease using unidimensional transient elastography (Fibroscan®)

Unidimensional transient elastography (TE) is a noninvasive technique, which has been increasingly used in the assessment of diffuse liver diseases. This paper focuses on reviewing the existing data on the use of TE in the diagnosis of fibrosis and in monitoring disease progression in alcoholic liver disease, on the factors that may influence the result of fibrosis prediction, and last but not least, on its potential use in assessing the steatosis degree. Therefore, this field is far from being exhausted and deserves more attention. Further studies are required, on large groups of biopsied patients, in order to find answers to all the remaining questions in this field.

Non-invasive diagnosis of liver fibrosis and cirrhosis

The evaluation and follow up of liver fibrosis and cirrhosis have been traditionally performed by liver biopsy. However, during the last 20 years, it has become evident that this “gold-standard” is imperfect; even according to its proponents, it is only “the best” among available methods. Attempts at uncovering non-invasive diagnostic tools have yielded multiple scores, formulae, and imaging modalities. All are better tolerated, safer, more acceptable to the patient, and can be repeated essentially as often as required. Most are much less expensive than liver biopsy. Consequently, their use is growing, and in some countries the number of biopsies performed, at least for routine evaluation of hepatitis B and C, has declined sharply. However, the accuracy and diagnostic value of most, if not all, of these methods remains controversial. In this review for the practicing physician, we analyze established and novel biomarkers and physical techniques. We may be witnessing in recent years the beginning of the end of the first phase for the development of non-invasive markers. Early evidence suggests that they might be at least as good as liver biopsy. Novel experimental markers and imaging techniques could produce a dramatic change in diagnosis in the near future.

Ultrasound-based elastography for the diagnosis of portal hypertension in cirrhotics

Progressive fibrosis is encountered in almost all chronic liver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered the reference method for staging the severity of fibrosis, but due to its drawbacks (inter and intra-observer variability, sampling errors, unequal distribution of fibrosis in the liver, and risk of complications and even death), non-invasive methods were developed to assess fibrosis (serologic and elastographic). Elastographic methods can be ultrasound-based or magnetic resonance imaging-based. All ultrasound-based elastographic methods are valuable for the early diagnosis of cirrhosis, especially transient elastography (TE) and acoustic radiation force impulse (ARFI) elastography, which have similar sensitivities and specificities, although ARFI has better feasibility. TE is a promising method for predicting portal hypertension in cirrhotic patients, but it cannot replace upper digestive endoscopy. The diagnostic accuracy of using ARFI in the liver to predict portal hypertension in cirrhotic patients is debatable, with controversial results in published studies. The accuracy of ARFI elastography may be significantly increased if spleen stiffness is assessed, either alone or in combination with liver stiffness and other parameters. Two-dimensional shear-wave elastography, the ElastPQ technique and strain elastography all need to be evaluated as predictors of portal hypertension.

Evaluation of Hepatitis C Patients in the Direct-Acting Antiviral Era

Hepatitis C is a major worldwide cause of liver morbidity and mortality. A substantial proportion of infected patients will develop chronic disease, which may progress over decades to cirrhosis. This can lead to decompensation and hepatocellular carcinoma. With the advent of the direct-acting antivirals, hepatitis C has become increasingly curable with limited adverse events and a shorter duration of therapy. This review discusses the evaluation process of the hepatitis C patient in the direct-acting antiviral era, including screening, clinical evaluation, drug-drug interactions, treatment urgency, and counseling.

Incorporation of Noninvasive Measures of Liver Fibrosis Into Clinical Practice: Diagnosis and Prognosis

Noninvasive methods are increasingly used for the assessment of liver fibrosis. Two categories of markers include serum-based markers (biologic properties) or ultrasound and magnetic resonance imaging-based techniques that use the principles of elastography (physical properties) to indirectly assess liver fibrosis. Serum markers can be either direct or indirect markers of the fibrosis process. Common elastography-based studies include vibration-controlled transient elastography, point shear wave elastography, and 2-dimensional shear wave elastography and magnetic resonance elastography. A common theme among all techniques is the inability to accurately differentiate between minimal or moderate stages of fibrosis but superior performance in identifying subjects with cirrhosis or normal liver parenchyma. Noninvasive markers may also serve as prognostic tools to course the natural history of chronic liver disease as well as identify cirrhotic patients at highest risk of future decompensation. Further research is needed to identify the role of noninvasive markers in following asymptomatic individuals, especially in patients with nonalcoholic fatty liver disease.

Non-invasive assessment of liver fibrosis in patients with alcoholic liver disease

Alcoholic liver disease (ALD) consists of a broad spectrum of disorders, ranging from simple steatosis to alcoholic steatohepatitis and cirrhosis. Fatty liver develops in more than 90% of heavy drinkers, however only 30%-35% of them develop more advanced forms of ALD. Therefore, even if the current “gold standard” for the assessment of the stage of alcohol-related liver injury is histology, liver biopsy is not reasonable in all patients who present with ALD. Currently, although several non-invasive fibrosis markers have been suggested as alternatives to liver biopsy in patients with ALD, none has been sufficiently validated. As described in other liver disease, the diagnostic accuracy of such tests in ALD is acceptable for the diagnosis of significant fibrosis or cirrhosis but not for lesser fibrosis stages. Existing data suggest that the use of non-invasive tests could be tailored to first tier screening of patients at risk, in order to diagnose early patients with progressive liver disease and offer targeted interventions for the prevention of decompensation. We review these tests and critically appraise the existing evidence.

Hepatitis C virus markers in infection by hepatitis C virus: In the era of directly acting antivirals

About 130-170 million people are infected with the hepatitis C virus (HCV) worldwide and more than 350000 people die each year of HCV-related liver diseases. The combination of pegylated interferon (Peg-IFN) and ribavirin (RBV) was recommended as the treatment of choice for chronic hepatitis C for nearly a decade. In 2011 the directly acting antivirals (DAA) HCV NS3/4A protease inhibitors, telaprevir and boceprevir, were approved to treat HCV-genotype-1 infection, each in triple combination with Peg-IFN and RBV. These treatments allowed higher rates of SVR than the double Peg-IFN + RBV, but the low tolerability and high pill burden of these triple regimes were responsible for reduced adherence and early treatment discontinuation. The second and third wave DAAs introduced in 2013-2014 enhanced the efficacy and tolerability of anti-HCV treatment. Consequently, the traditional indicators for disease management and predictors of treatment response should be revised in light of these new therapeutic options. This review article will focus on the use of the markers of HCV infection and replication, of laboratory and instrumental data to define the stage of the disease and of predictors, if any, of response to therapy in the DAA era. The article is addressed particularly to physicians who have patients with hepatitis C in care in their everyday clinical practice.

[Ultrasound elastography]

Noninvasive, ultrasound-based methods for visualizing and measuring tissue elasticity are becoming more and more common in routine practice. Using hepatic shear wave elastography, cut-off levels can help to detect the degree of relevant fibrosis (F ≥ 2) with a diagnostic accuracy using the area under the reader operating characteristic (AUROC) of 87 % and cirrhosis (F = 4, AUROC 93 %). Normal values virtually exclude liver cirrhosis (negative predictive value up to 97 %) and high shear wave velocities predict complications in the course of primary sclerosing cholangitis, liver cirrhosis and chronic hepatitis B or C. Elastography is of no relevant help in the differentiation of the dignity of hepatic lesions. Concerning thyroid or breast lesions, low shear wave velocities are indicative of benign lesions and in contrast, high velocities of malignant lesions. A differentiation between benign and malignant thyroid nodules is performed by elastography with a sensitivity of 89 % and a specificity of 82 %. In breast lesions a differentiation of nodes can be improved with elastography compared to B-mode ultrasound alone with a sensitivity of 97 % and a specificity of 83 %. Invasive biopsy punctures can therefore be specifically performed or can be omitted. Due to several influencing factors, in particular during liver elastography, the measurements need to be interpreted in the clinical context. In summary, ultrasound-based elastography provides helpful information for the detection of hepatic fibrosis and for further characterization of thyroid or breast lesions in addition to classical techniques, such as B-mode imaging and color Doppler.

Accuracy of transient elastography in assessing liver fibrosis in chronic viral hepatitis: A multicentre, retrospective study

BACKGROUND/AIMS

Transient elastography (TE) has become an alternative to liver biopsy (LB). This study investigated the diagnostic performance of liver stiffness (LS) measurement using TE in Korean patients with chronic hepatitis B and C (CHB and CHC).

METHODS

From April 2006 to June 2014, 916 patients (567 CHB and 349 CHC) who underwent LB and TE at 15 centres were analyzed. The Batts and Ludwig scoring system was used for histologic assessment. Aspartate aminotransferase (AST)-to-platelet ratio indexes (APRI) were calculated. Area under the receiver operating characteristic curve (AUROC) was used.

RESULTS

The median age, LS value, and APRI score were 45 years, 8.8 kPa, and 0.61, respectively, in CHB patients vs. 51 years, 6.8 kPa and 0.55, respectively, in CHC patients. TE was significantly superior to APRI in CHB patients (AUROC 0.774 vs. 0.72 for ≥F2, 0.849 vs. 0.812 for ≥F3, and 0.902 vs. 0.707 for F4, respectively; all P < 0.05). Furthermore, TE was significantly superior for predicting ≥ F3 stage (AUROC 0.865 vs. 0.840, P = 0.009) whereas it was similar for predicting ≥ F2 and F4 stage (AUROC 0.822 vs. 0.796; 0.910 vs. 0.884; all P > 0.05) in CHC patients. In CHB patients, optimal cut-off LS values were 7.8 kPa for ≥F2, 8.2 kPa for ≥ F3, and 11.6 kPa for F4, vs. 6.8 kPa, 8.6 kPa, and 14.5 kPa, respectively, in CHC patients.

CONCLUSIONS

TE can accurately assess the degree of liver fibrosis in Korean patients with CVH. TE was superior to APRI for predicting each fibrosis stage.

Nonalcoholic fatty liver disease - current status and future directions

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most common chronic liver disease worldwide with a reported prevalence ranging 6-33%, depending on the studied populations. It encompasses a spectrum of liver manifestations ranging from simple steatosis (also known as nonalcoholic fatty liver, NAFL) to nonalcoholic steatohepatitis (NASH), fibrosis and cirrhosis, which may ultimately progress to hepatocellular carcinoma. NAFLD is strongly associated with the components of metabolic syndrome, mainly obesity and type 2 diabetes mellitus. NAFLD patients are at increased risk of liver-related as well as cardiovascular mortality. Current paradigm suggests a benign course for NAFL whereas NASH is considered to be the progressive phenotype. Although previously under-recognized accumulating evidence suggests that NAFL may also progress, suggesting a higher number of patients at risk than previously appreciated. Liver biopsy remains the gold standard for definitive diagnosis, but the majority of patients can be diagnosed accurately by noninvasive methods. Approved therapies for NAFLD are still lacking and lifestyle modifications aiming at weight loss remain the mainstay of NAFLD treatment. Intensive research could identify insulin resistance, lipotoxicity and dysbiosis of the gut microbiota as major pathophysiological mechanisms, leading to the development of promising targeted therapies which are currently investigated in clinical trials. In this review we summarized the current knowledge of NAFLD epidemiology, natural history, diagnosis, pathogenesis and treatment and considered future directions.

Final Results of the Telaprevir Access Program: FibroScan Values Predict Safety and Efficacy in Hepatitis C Patients with Advanced Fibrosis or Cirrhosis

Background

Liver stiffness determined by transient elastography is correlated with hepatic fibrosis stage and has high accuracy for detecting severe fibrosis and cirrhosis in chronic hepatitis C patients. We evaluated the clinical value of baseline FibroScan values for the prediction of safety and efficacy of telaprevir-based therapy in patients with advanced fibrosis and cirrhosis in the telaprevir Early Access Program HEP3002.

Methods

1,772 patients with HCV-1 and bridging fibrosis or cirrhosis were treated with telaprevir plus pegylated interferon-α and ribavirin (PR) for 12 weeks followed by PR alone, the total treatment duration depending on virological response and previous response type. Liver fibrosis stage was determined either by liver biopsy or by non-invasive markers. 1,282 patients (72%) had disease stage assessed by FibroScan; among those 46% were classified as Metavir F3 at baseline and 54% as F4.

Results

Overall, 1,139 patients (64%) achieved a sustained virological response (SVR) by intention-to-treat analysis. Baseline FibroScan values were tested for association with SVR and the occurrence of adverse events. By univariate analysis, higher baseline FibroScan values were predictive of lower sustained virological response rates and treatment-related anemia. By multivariate analysis, FibroScan was no longer statistically significant as an independent predictor, but higher FibroScan values were correlated with the occurrence of infections and serious adverse events.

Conclusions

FibroScan has a limited utility as a predictor of safety and efficacy in patients treated with telaprevir-based triple therapy. Nevertheless it can be used in association with other clinical and biological parameters to help determine patients who will benefit from the triple regiments.

Trial Registration

ClinicalTrials.gov NCT01508286

Liver and spleen transient elastography and Acoustic Radiation Force Impulse Measurements. Performance and comparison of measurements in the same area concurrently assessed for liver fibrosis by biopsy

PURPOSE

The estimation of the degree of liver fibrosis is important for prognosis, surveillance, and treatment of chronic liver disease. Although liver biopsy is the gold standard for diagnosis, it is subject to sampling error, while ultrasound-based techniques, such as Acoustic Radiation Force Impulse (ARFI) and transient elastography, have gained popularity. However, no previous comparative study has performed these ultrasound techniques at the time of biopsy. The aim of this study was to compare the reliability of these techniques to define the severity of liver fibrosis in viral hepatitis patients.

PATIENTS AND METHODS

We compared liver transient elastography and Acoustic Radiation Force Impulse measurements, performed along the intended biopsy track, with liver biopsy results in 46 viral hepatitis patients, all measured on the same morning. Fibrosis was measured by histology using the Ishak fibrosis staging.

RESULTS

The relative sensitivity and specificity of different incremental cut-off values for both techniques, and the predictive ability of pairwise comparison of the 3 tests (including APRI) and of their combined use with more severe grades of histology-measured liver fibrosis, show that the single variable with greatest sensitivity and specificity is TE with a cut-off of >10.0.

CONCLUSION

Transient elastography has a better performance than ARFI, which has a lower sensitivity, in the diagnosis of severe stages of fibrosis. Also ARFI of the spleen is correlated with Ishak fibrosis staging, and could be a possible additional tool for the diagnosis of liver fibrosis.

Performance of 2-D shear wave elastography in liver fibrosis assessment compared with serologic tests and transient elastography in clinical routine

Liver stiffness values assessed with 2-D shear wave elastography (SWE), transient elastography (TE) and simple serologic tests were compared with respect to non-invasive assessment in a cohort of 127 consecutive patients with chronic liver diseases. The rate of reliable liver stiffness measurements was significantly higher with 2-D SWE than with TE: 99.2% versus 74.8%, p < 0.0001 (different reliability criteria used, according to current recommendations). In univariate analysis, liver stiffness measured with 2-D SWE correlated best with fibrosis stage estimated with TE (r = 0.699, p < 0.0001), followed by Forns score (r = 0.534, p < 0.0001) and King's score (r = 0.512, p < 0.0001). However, in multivariate analysis, only 2-D SWE-measured values remained correlated with fibrosis stage (p < 0.0001). The optimal 2-D SWE cutoff values for predicting significant fibrosis were 8.03 kPa for fibrosis stage ≥2 (area under the receiver operating characteristic curve = 0.832) and 13.1 kPa for fibrosis stage 4 (area under the receiver operating characteristic curve = 0.915), respectively. In conclusion, 2-D SWE can be used to obtain reliable liver stiffness measurements in almost all patients and performs very well in predicting the presence of liver cirrhosis.

Noninvasive Assessment of Liver Fibrosis

BACKGROUND

The prognosis and management of chronic liver diseases greatly depend on the amount and progression of liver fibrosis with the risk of developing cirrhosis. Liver biopsy, traditionally considered as the reference standard for the staging of fibrosis, has been challenged over the past decade by the development of novel noninvasive methodologies. Key Messages: Noninvasive methods rely on two different but complementary approaches: a 'biological' approach based on the dosage serum biomarkers, and a 'physical' approach based on the measurement of liver stiffness using transient elastography (TE). There are two clinically relevant endpoints for the staging of liver fibrosis: (1) significant fibrosis (indication for antiviral treatment in viral hepatitis B and C), and (2) cirrhosis (indication for screening of esophageal varices and hepatocellular carcinoma). TE (FibroScan®), FibroTest® and APRI have been the most extensively studied and validated methods, mainly in chronic hepatitis C. Combining two unrelated methods, such as TE and biomarkers, is an attractive approach that increases diagnostic performance and limits the drawback of both methodologies. TE appears to be an excellent tool for the early detection of cirrhosis with likely prognostic value in this setting. Thus far, however, it cannot replace upper endoscopy for screening of esophageal varices. The main limitation of TE in clinical practice is the impossibility of obtaining reliable liver stiffness measurements in around 20% of cases, mainly comprising obese patients.

CONCLUSION

An increasing number of reliable noninvasive methods are now available that are widely used in clinical practice, mostly in viral hepatitis, resulting in a significant decrease in the need for liver biopsy.

Evaluation of Acoustic Radiation Force Impulse Imaging (ARFI) for the Determination of Liver Stiffness Using Transient Elastography as a Reference in Children

PURPOSE

Transient elastography (Fibroscan(©); (FS)) and acoustic radiation force impulse imaging (ARFI) represent noninvasive, user-friendly and quick methods providing an objective and reproducible measure of liver stiffness. The aim of the study was to evaluate cut-off values and performance of ARFI measurements in children using transient elastography as a reference.

METHODS/PATIENTS

A total of 198 children were enrolled in this study. All patients underwent liver stiffness measurements with FS (FS-LS) as well as ARFI (with shear wave velocity quantification; ARFI-SWV) and the performance of ARFI in comparison to FS was studied.

RESULTS

Significantly higher rates of successful measurements were found for ARFI compared to FS (198/198 (100%) vs. 160/198 (80.8%); p<0.001). ARFI-SWV correlated significantly with FS-LS (r=0.751, p=0.001). ARFI-SWV increased significantly with the stage of fibrosis (1.19+0.15 m/s for patients with FS-LS<7.6 kPa); 1.34+0.22 m/s for patients with 7.613.0 kPa). ARFI-SWV cut-off values were identified for no significant fibrosis (1.31 m/s; sensitivity 61.8% and specificity 79.5%) and for liver cirrhosis (1.63 m/s; sensitivity 70.0% and specificity 97.4%). The median values of liver stiffness measured by FS were age-dependent in 90 children without liver diseases with 4.8, 5.6, and 5.7 kPa in children 0-5, 6-11, and 12-18 years, respectively.

Factors Associated with the Quality of Transient Elastography

BACKGROUND

Transient elastography is a noninvasive method for the evaluation of fibrosis in chronic liver disease. However, its reliability is variable, and the factors associated with its accuracy have not been identified completely.

AIMS

To identify the factors associated with the reliability of transient elastography.

METHODS

A total of 2033 transient elastography measurements were taken from March 2009 to October 2013. Reliability was determined according to the interquartile range/median (IQR/M < 0.30 = reliable; IQR/M < 0.10 = very reliable). Other indicators such as the percentage of successful measurements (>60 %), time of performance, and probe size were recorded. Potential factors that could affect the reliability of the procedure were analyzed using multivariate logistic regression.

RESULTS

Slightly less than 5 % of the measurements were unsuccessful, and 83 % of the successful measurements were found to be reliable. Factors associated with an unsuccessful measurement were female gender, incorrect probe size, and the presence of HCV infection. Unreliable measurements were associated with use of the procedure as part of a clinical study and success rate. Very reliable evaluations were associated with >10 measurements, the presence of chronic hepatic disease, and a success rate of >60 %.

CONCLUSIONS

The operator and clinical and anthropometric characteristics are factors that influence the success and reliability of transient elastography. Improvements in the quality of the procedure are needed to provide better diagnostic accuracy in clinical practice.

Liver ultrasound elastography: More than staging the disease

Ultrasound elastography is perhaps the most important breakthrough in the evolution of ultrasonography in the last 15 years. Since transient elastography was introduced, many other methods have been developed and became more and more widely available. The value of ultrasound elastography in staging a chronic liver disease has been established by numerous studies. There have been many studies that have shown that using liver elastography it is possible to predict the presence of the complications of cirrhosis: portal hypertension, presence of esophageal varices (and even their risk of bleeding) and hepatocellular carcinoma. It has been shown that liver elastography can predict the progression of liver fibrosis and also the survival (hepatic events - free) of the patients with chronic liver diseases. These are the real quests of the clinicians, this is the ultimate scope of any medical investigation - to predict the outcome of a patient and to help making therapeutic decisions. I brought together only a small amount of the data that has already been written on this subject to support my affirmation that liver ultrasound elastography is more than a tool for staging the liver disease, but it is also comparable to a crystal ball which in the hands of a skilled clinician can reveal the future of the patient and can help to improve this future.

Current and future directions for treating hepatitis B virus infection

Hepatitis B virus (HBV) persistently infects approximately 350 million people, and approximately 600000 liver-related deaths are observed per year worldwide. HBV infection is also one of the major risk factors for hepatocellular carcinoma (HCC). The persistence of serum hepatitis B e antigen (HBeAg) and high level of serum HBV DNA are thought to reflect a high HBV replication status in hepatocytes, causing cirrhosis, HCC and liver-related deaths. It has been reported that antiviral therapy, such as peginterferon and nucleos(t)ide analogues (NUCs), could suppress liver-related death by inhibiting the HBV DNA levels and inducing seroconversion from HBeAg to antibody to HBe antigen. Currently, peginterferon is widely used, but there are also several disadvantages in the use of peginterferon, such as various adverse events, the administration route and duration. It is difficult to predict the effects of treatment and interferon is contraindicated for the patients with advanced fibrosis of the liver and cirrhosis. With respect to NUCs, entecavir and tenofovir disoproxil fumarate are current the first-choice drugs. NUCs can be administered orally, and their anti-viral effects are stronger than that of peginterferon. However, because cessation of NUC administration leads to high levels of viral replication and causes severe hepatitis, they must be administered for a long time. On the other hand, the use of both interferon and NUCs cannot eliminate covalently closed circular DNA of HBV. In this review, we evaluate the natural course of chronic HBV infection and then provide an outline of these representative drugs, such as peginterferon, entecavir and tenofovir disoproxil fumarate.

Elastography Assessment of Liver Fibrosis: Society of Radiologists in Ultrasound Consensus Conference Statement

The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, hepatology, pathology, and basic science and physics to arrive at a consensus regarding the use of elastography in the assessment of liver fibrosis in chronic liver disease. The panel met in Denver, Colo, on October 21-22, 2014, and drafted this consensus statement. The recommendations in this statement are based on analysis of current literature and common practice strategies and are thought to represent a reasonable approach to the noninvasive assessment of diffuse liver fibrosis.

Longer duration of transient elastography predicts unreliable liver stiffness measurements

BACKGROUND

Transient elastography (TE) is a noninvasive, validated method to assess liver fibrosis by obtaining liver stiffness measurements (LSM). However, TE can be limited by unreliable measurement (UM). The relationship between the time taken to perform TE (duration) and UM has not been studied.

OBJECTIVES

To determine whether the duration of TE correlates with UM.

MATERIALS AND METHODS

We prospectively studied the frequency and predictors of UM over a 5-year period. UM was defined as follows: less than 10 successful measurements, success rate less than 60%, or interquartile range more than 30% of the median LSM value (IQR/LSM>30%).

RESULTS

Among the 2834 patients with LSM analysed, UM occurred in 19.0%. Duration [odds ratio (OR) 4.2, 95% confidence interval (CI) 2.8-6.4; P<0.0001] was the strongest predictor of UM, followed by BMI more than 28 kg/m (OR 2.1, 95% CI 1.5-3.0; P<0.0001), age more than 52 (OR 1.6, 95% CI 1.1-2.3; P=0.007) and non-HBV aetiology (OR 1.6, 95% CI 1.1-2.3; P=0.02). An optimal cut-off of 3 min 47 s was calculated for predicting UM (sensitivity 70%, specificity 65%, OR 4.2, 95% CI 2.7-6.6, P<0.0001). Examinations that took longer than 8 min 10 s had a 90% chance of UM.

CONCLUSION

In experienced hands, duration is a strong predictor of UM in patients undergoing TE. Examinations longer than 4 min are more likely to be unreliable. Examinations longer than 8 min are unlikely to yield a valid result and should be considered a futility endpoint. Older age and increased BMI and nonhepatitis B aetiology are independent, albeit weaker, predictors of UM.

Liver Fibrosis by Transient Elastography and Virologic Outcomes After Introduction of Tenofovir in Lamivudine-Experienced Adults With HIV and Hepatitis B Virus Coinfection in Ghana

BACKGROUND

Antiretroviral treatment (ART) programs in sub-Saharan Africa have for many years included lamivudine as the sole hepatitis B virus (HBV) inhibitor. Long-term outcomes and the effects of introducing tenofovir as part of ART in these populations have not been characterized.

METHODS

The study comprised a cross-sectional analysis of 106 human immunodeficiency virus (HIV)/HBV-coinfected subjects maintained on lamivudine, as well as a prospective analysis of 76 lamivudine-experienced subjects who introduced tenofovir. Patients underwent assessment of liver fibrosis by transient elastography (TE) and testing to characterize HIV type 1 (HIV-1) and HBV replication.

RESULTS

After a median of 45 months of lamivudine treatment, HIV-1 RNA and HBV DNA were detectable in 35 of 106 (33.0%) and 54 of 106 (50.9%) subjects, respectively, with corresponding drug resistance rates of 17 of 106 (16.0%) and 31 of 106 (29.2%), respectively. Median TE values were 5.7 kPa (interquartile range, 4.7-7.2 kPa) and independently associated with HBV DNA load, aspartate aminotransferase levels, and platelet counts; 13 of 106 (12.3%) subjects had TE measurements >9.4 kPa. Twelve months after the first assessment, and a median of 7.8 months after introducing tenofovir, HBV DNA levels declined by a mean of 1.5 log10 IU/mL (P < .001). TE values changed by a mean of -0.2 kPa (P = .097), and declined significantly in subjects who had pretenofovir HBV DNA levels >2000 IU/mL (mean, -0.8 kPa; P = .048) or TE values >7.6 kPa (mean, -1.2 kPa; P = .021). HIV-1 RNA detection rates remained unchanged.

CONCLUSIONS

A proportion of HIV/HBV-coinfected patients on long-term lamivudine-containing ART had poor HIV and HBV suppression, drug resistance, and TE values indicative of advanced liver fibrosis. Tenofovir improved HBV control and reduced liver stiffness in subjects with high HBV DNA load and TE values.

Soluble CD146, a novel endothelial marker, is related to the severity of liver disease

OBJECTIVES

Angiogenesis and inflammation have been involved in the progression of fibrosis in patients with chronic liver disease (CLD). Soluble CD146 (sCD146), a biomarker that was recently characterized as a novel component of the endothelial junction is implicated in endothelial proliferation. Our study evaluates the performance of sCD146 in assessing liver fibrosis and cirrhosis, and determines if its levels are related to the severity of liver disease in patients with cirrhosis.

MATERIAL AND METHODS

sCD146 levels were determined by a commercially available immunoenzymatic technique in 62 consecutive patients with cirrhosis, 43 patients with CLD and 27 healthy controls.

RESULTS

Patients with cirrhosis compared to non-cirrhotics with CLD had a higher median sCD146 concentration (639 vs. 317 ng/ml). In receiver operating characteristic (ROC) curve analysis, the cut-off of 412 ng/ml showed a sensitivity of 78% and a specificity of 75% for diagnosis of cirrhosis, offering good diagnostic accuracy (area under the ROC curve [AUROC: 0.838]). Patients with compensated compared to those with decompensated cirrhosis had a lower median sCD146 concentration (399 vs. 848 ng/ml, respectively). A cut-off of 534 ng/ml offered a sensitivity of 83% and a specificity of 78% for differentiating compensated from decompensated cirrhosis (AUROC: 0.866). Furthermore, in cirrhotics, sCD146 correlated positively with AST, bilirubin levels and most importantly with international normalized ratio and model for end-stage liver disease (r = 0.648, p < 0.001 and r = 0.567, p < 0.001, respectively).

CONCLUSION

sCD146 can be used as a surrogate, inexpensive biomarker for the diagnosis of cirrhosis. It is also well correlated with severity of liver disease in cirrhotic patients. Further studies are needed to define its role in clinical practice.

WFUMB guidelines and recommendations for clinical use of ultrasound elastography: Part 3: liver

The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced these guidelines for the use of elastography techniques in liver disease. For each available technique, the reproducibility, results, and limitations are analyzed, and recommendations are given. Finally, recommendations based on the international literature and the findings of the WFUMB expert group are established as answers to common questions. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of liver diseases.

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.

Ultrasound Elastography and MR Elastography for Assessing Liver Fibrosis: Part 2, Diagnostic Performance, Confounders, and Future Directions

OBJECTIVE

The purpose of the article is to review the diagnostic performance of ultra-sound and MR elastography techniques for detection and staging of liver fibrosis, the main current clinical applications of elastography in the abdomen.

CONCLUSION

Technical and instrument-related factors and biologic and patient-related factors may constitute potential confounders of stiffness measurements for assessment of liver fibrosis. Future developments may expand the scope of elastography for monitoring liver fibrosis and predict complications of chronic liver disease.

Liver and spleen stiffness and their ratio assessed by real-time two dimensional-shear wave elastography in patients with liver fibrosis and cirrhosis due to chronic viral hepatitis

OBJECTIVES

To investigate the performance of real-time 2D shear wave elastography (RT 2D-SWE) for non-invasive staging of liver disease in patients with chronic viral hepatitis (CVH).

MATERIALS AND METHODS

Naive CVH patients underwent liver (LS) and spleen stiffness (SS) measurements by an intercostal approach. Patients with ALT >3× upper limit of normal, cholestasis as revealed by dilated intrahepatic biliary tree, and liver congestion were excluded. Results were expressed in kPa and compared to histological stage (Ishak) of liver fibrosis (LF). Patients with decompensated liver cirrhosis (LC) were diagnosed using standard clinical, ultrasound, and endoscopic criteria.

RESULTS

Of 123 patients, LS was successfully measured in 79.7% and SS in 53.7%. LS accurately differentiated between liver disease stages, with cut-off values of 8.1 (AUC 0.991) for F ≥ 3, 10.8 kPa (AUC 0.954) for F ≥ 5, and 27 kPa (AUC 0.961) for decompensated LC. SS was significantly different between non-cirrhotic stages (F0-4) and LC (cut-off 24 kPa; AUC 0.821). While both LS and SS increased with liver disease progression, the difference between them decreased, as reflected by the stiffness ratio index.

CONCLUSIONS

RT 2D-SWE can accurately differentiate between the stages of LF, and can distinguish LF from LC and compensated from decompensated LC.

KEY POINTS

• RT 2D-SWE is an accurate method for assessment of liver fibrosis. • RT 2D-SWE is applicable in 80% of patients with chronic viral hepatitis. • RT 2D-SWE accurately differentiates compensated from decompensated liver cirrhosis. • Both liver and spleen stiffness increase with progression of liver fibrosis. • In cirrhosis, the difference between liver and spleen stiffness decreases.

Biomarkers in HCV Infection

Liver-related biomarkers have been developed and validated mainly in patients with chronic hepatitis C for the prediction of liver fibrosis or cirrhosis, which is a final pathway of chronic liver injury. They are noninvasive, traceable, and easy-to-use. Biomarkers provide implications related to screening, diagnosis, treatment, and prognosis of chronic hepatitis. For the improvement of performance and coverage, biomarker panels, imaging biomarkers, and even genetic biomarkers have been developed. With the advancement of genomics and proteomics, earlier and more precise prediction is expected in the near future. In this review, multiple biomarker panels for the estimation of the degree of fibrosis in chronic hepatitis C, biomarkers for the screening and diagnosis of hepatitis C, biomarkers for the treatment of hepatitis C, biomarkers for the prediction of complications related to the chronic hepatitis C, and future perspectives will be summarized.

Quantitative assessment of liver fibrosis by digital image analysis: Relationship to Ishak staging and elasticity by shear-wave elastography

OBJECTIVE

To analyze the relationship between fibrosis staged by Ishak stage and quantified by digital image analysis (DIA), and to reveal the optimum performance of shear-wave elastography (SWE) using quantitative DIA measurements as a comparative histological standard.

METHODS

The proportionate area (PA) of fibrosis was measured by DIA from images of the PA of trichrome-stain (TPA) of 168 chronic hepatitis patients. SWE was performed in 105 patients. The accuracy of SWE for predicting the fibrosis defined by quantitative PA thresholds (≥ 2.5%, ≥ 5%, ≥ 10% and ≥ 20%, respectively) and by Ishak stages was measured using the area under the receiver operating characteristic curve (AUROC).

RESULTS

DIA was proven to be highly reproducible (interclass correlation coefficient  0.926). The TPA range corresponding to each Ishak stage was large, widened as stages progressed, and reached its greatest extent in cirrhosis. TPA magnified at ×50 ranges 11.9-56% for Ishak stage F5-6. A good correlation between TPA and elasticity was presented for more advanced fibrosis (TPA ≥10%, rs  = 0.732, P = 0.000) than milder fibrosis (TPA <10%, rs  = 0.308, P = 0.006). With the advance of fibrosis either by stages or PA thresholds the discriminative accuracy of SWE gradually increased, but was less satisfactory for milder fibrosis.

CONCLUSIONS

DIA may serve as a reproducible and reliable quantitative standard for surrogate tests for liver fibrosis. The performance and correlation of SWE with the fibrotic extent were better for advanced fibrosis, but less satisfactory for milder fibrosis.

Liver fibrosis, microbial translocation and immune activation markers in HIV and HCV infections and in HIV/HCV co-infection

BACKGROUND

Liver fibrosis is accelerated in patients co-infected with human immunodeficiency virus and hepatitis C viruses.

AIMS

We investigated the correlation between liver fibrosis, immune activation and microbial translocation.

METHODS

This cross-sectional study included patients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) mono-infections, HIV/HCV co-infection, and healthy controls (20 subjects/group). Peripheral blood was analysed to determine the levels of Forkhead box 3 (Foxp3) T cells, TGF-β1, CD14 (soluble and surface isoforms), IL-17 and bacterial translocation products. These measurements were correlated to the severity of liver fibrosis, measured with the FIB-4 score and transient elastography.

RESULTS

Foxp3T cell levels were significantly elevated in HIV mono-infected and co-infected groups (p<0.0005). FIB-4 and liver stiffness values inversely correlated with TGF-β1 (p=0.0155 and p=0.0498). Bacterial DNA differed significantly in the HIV-positive compared to the other groups: HIV/HCV co-infected subjects had significantly higher serum levels of bacterial translocation products, CD14, and IL-17 levels (p<0.001).

CONCLUSIONS

Fibrosis stage in HIV/HCV co-infection may be influenced by immune activation due either by viral infections or to bacterial translocation.

Hepascore and hyaluronic acid as markers of fibrosis in liver disease of mixed aetiology

OBJECTIVE

To evaluate hyaluronic acid (HA) and Hepascore as diagnostic replacements for liver biopsy in a population with mixed liver disease.

MATERIALS AND METHODS

The utility of HA concentration and Hepascore for staging fibrosis, detecting any fibrosis and detecting advanced fibrosis, was assessed in 73 consecutive patients, with varied liver pathologies requiring biopsy. Subgroup analyses compared utility of disease-specific and universal cut-offs for HA and Hepascore.

RESULTS

Forty-one patients (56.2%) had liver fibrosis on biopsy. HA and Hepascore varied significantly with METAVIR stage, although ranges overlapped, precluding their use in staging fibrosis. When detecting any fibrosis (METAVIR F1-F4), HA and Hepascore had areas under the receiver operator characteristic curve of 0.63 and 0.66, respectively, and approximately two-thirds of patients were correctly categorized using optimal cut-offs. For detection of advanced fibrosis (METAVIR F3/4), HA and Hepascore had areas under the receiver operator characteristic curve of 0.81 and 0.80, respectively, and three-quarters of patients were correctly categorized using optimal cut-offs. In subgroup analysis, locally derived, disease-specific cut-offs in hepatitis C virus patients yielded greatest diagnostic efficiency, whereas the tests performed worst in cryptogenic aetiologies.

CONCLUSION

HA and Hepascore cannot accurately stage hepatic fibrosis in this population. Locally derived, disease-specific cut-offs for HA gave the higher diagnostic efficiency observed. Although HA and Hepascore may be useful where the disease aetiology is known, particularly in established hepatitis C virus, the high cost of false positives and false negatives are such that neither a reliable enough to replace biopsy without substantial further characterization.

New imaging techniques for liver diseases

Newly developed or advanced methods of ultrasonography and MR imaging provide combined anatomical and quantitative functional information about diffuse and focal liver diseases. Ultrasound elastography has a central role for staging liver fibrosis and an increasing role in grading portal hypertension; dynamic contrast-enhanced ultrasonography may improve tumor characterization. In clinical practice, MR imaging examinations currently include diffusion-weighted and dynamic MR imaging, enhanced with extracellular or hepatobiliary contrast agents. Moreover, quantitative parameters obtained with diffusion-weighted MR imaging, dynamic contrast-enhanced MR imaging and MR elastography have the potential to characterize further diffuse and focal liver diseases, by adding information about tissue cellularity, perfusion, hepatocyte transport function and visco-elasticity. The multiparametric capability of ultrasonography and more markedly of MR imaging gives the opportunity for high diagnostic performance by combining imaging biomarkers. However, image acquisition and post-processing methods should be further standardized and validated in multicenter trials.

Australian Liver Association (ALA) expert consensus recommendations for the use of transient elastography in chronic viral hepatitis

Since the introduction of Transient Elastography (TE) into Australia in 2008, non-invasive liver fibrosis assessments have integrated themselves into clinical hepatology. The Australian Liver Association (ALA) recognizes these technologies perform an important role in the assessment of chronic viral hepatitis B and C. However, in the setting of viral hepatitis and many other chronic liver diseases, there remains no consensus or guidelines regarding the performance, utility or reporting of TE. Accordingly, the ALA sought to produce an expert consensus statement for the use of TE in chronic viral hepatitis. The recommendations incorporated in this document are based upon a thorough literature review and draw on extensive clinical experience using TE. The initial draft was presented at Australian Gastroenterology Week (AGW) 2013. Through a collaborative process and expert external review a finalized document was presented at AGW 2014.

The role of liver stiffness measurement in the evaluation of liver function and esophageal varices in cirrhotic patients

OBJECTIVE

We aimed to evaluate the efficacy of liver stiffness measurement (LSM) in predicting the presence and severity of esophageal varices (EV) and investigating its association with liver function (LF) in patients with liver cirrhosis.

METHODS

Medical records of 90 cirrhotic patients who underwent LSM by transient elastography were retrospectively reviewed. The relationship between LSM and the presence and severity of EV was evaluated by esophagogastroduodenoscopy (EGD) and multislice spiral computed tomography (MSCT). Another 25 healthy individuals were included as controls.

RESULTS

LSM was significantly associated with the Child-Pugh score in cirrhotic patients, with the highest LSM in those with Child-Pugh C. Patients with clinically decompensated cirrhosis had a higher LSM than those with compensated cirrhosis (36.75 ± 16.54 kPa vs 17.65 ± 10.87 kPa, P < 0.01). However, there was no significant difference in LSM value between patients with severe EV and those with no or non-severe EV determined by endoscopy (28.18 ± 17.44 kPa vs 31.00 ± 18.44 kPa) or MSCT (29.71 ± 18.39 kPa vs 24.90 ± 14.80 kPa). The diagnostic value of LSM for predicting severe EV was low in unselected cirrhotic patients. The presence of EV examined by EGD and MSCT was similar to each other.

CONCLUSIONS

LSM could be used to evaluate the progression of liver cirrhosis continuously. However, its role in assessing EV grades in advanced cirrhosis needs further confirmation. MSCT can assess EV accurately and may serve as an alternative to endoscopy in the assessment of portal hypertension.

New reliability criteria for transient elastography increase the number of accurate measurements for screening of cirrhosis and portal hypertension

BACKGROUND & AIMS

Transient elastography (TE) can non-invasively diagnose cirrhosis and portal hypertension (PHT). New TE reliability criteria suggest classifying measurements as very reliable (IQR/M < 0.1), reliable (IQR<0.3 or >0.3, if TE < 7.1 kPa) and poorly reliable (IQR/M > 0.3, if TE > 7.1 kPa). Compare traditional (reliable: success rate >60% + IQR/M ≤ 0.30) and new TE quality criteria (accurate: very reliable + reliable) regarding their diagnostic accuracy for cirrhosis and PHT and to identify potential confounders (age, aetiology, necroinflammatory activity, steatosis, siderosis, cholestasis, aminotransferases) of TE performance.

METHODS

Patients undergoing simultaneous measurements of TE, portal pressure (hepatic venous pressure gradient, HVPG) and liver biopsy were analysed.

RESULTS

Among 226 patients (48.7 ± 13.1 years, 74.7% male, 75.7% viral aetiology, 57% F3/F4), traditional TE quality criteria identified 71.6% reliable measurements, while new criteria yielded in 83.2% accurate results. Reliable TE values according to both criteria significantly correlated with fibrosis stage (r = 0.648 vs. r = 0.636) and HVPG (r = 0.836 vs. r = 0.846). Diagnostic accuracy for cirrhosis (cut-off >14.5 kPa) was 76.5% (AUC: 0.863) and 75.0% (AUC: 0.852) for traditional and new TE criteria, respectively, while for predicting HVPG ≥ 10 mmHg (>16.1 kPa), the accuracies were 88.9% (AUC: 0.957) and 89.8% (AUC: 0.962). New TE criteria allowed a better discrimination of reliable and non-reliable results for prediction of fibrosis and CSPH. Only aetiology and aminotransferases were independent confounders of the correlation of TE and fibrosis stage, while no confounder affected the correlation of TE and HVPG.

CONCLUSIONS

New reliability criteria for TE measurements increase the number of patients with accurate measurements without affecting diagnostic performance for detecting cirrhosis and portal hypertension. Aetiology of liver disease and aminotransferases should be considered when assessing liver fibrosis by TE.