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

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.

Hepatitis B: are non-invasive markers of liver fibrosis reliable?

Liver biopsy, which was traditionally considered to be the gold standard for the staging of fibrosis, has been challenged in the past decade by non-invasive techniques. These techniques rely on two distinct but complementary approaches: a 'biological' approach, based on the quantification of biomarkers of fibrosis in serum, and a 'physical' approach, based on the measurement of liver stiffness using elastography-based technologies. Advantages of serum biomarkers include their high applicability (>95%) and good reproducibility. However, as none are liver specific their results can be influenced by comorbid conditions (risk of false positive results with FibroTest in patients with Gilbert's syndrome or with APRI in case of acute hepatitis). Transient elastograpy has the advantages of being a user's friendly procedure that can be performed at the bedside or in an outpatient clinic with high performance for detecting cirrhosis. However, its applicability is lower (80%) than that of serum biomarker (particularly in case of ascites, obesity and limited operator experience) with the risk of false positive results in case of ALT flares. Although these non-invasive methods were initially developed and validated in patients with chronic hepatitis C, they are now increasingly used in patients with hepatitis B, reducing the need for liver biopsy.

Review article: The prevention and reversal of hepatic fibrosis in autoimmune hepatitis

BACKGROUND

Immunosuppressive treatment of autoimmune hepatitis can prevent or reverse hepatic fibrosis, but these anti-fibrotic effects are inconsistent secondary gains.

AIM

To describe the anti-fibrotic effects of current therapies for autoimmune hepatitis, discuss the pathogenic mechanisms of hepatic fibrosis that might be targeted by anti-fibrotic interventions, indicate the non-invasive diagnostic tests of hepatic fibrosis that must be validated in autoimmune hepatitis and to suggest promising treatment opportunities.

METHODS

Studies cited in PubMed from 1972 to 2013 for autoimmune hepatitis, hepatic fibrosis, cirrhosis, anti-fibrotic therapy and non-invasive tests of hepatic fibrosis were selected.

RESULTS

Hepatic fibrosis improves in 53-57% of corticosteroid-treated patients with autoimmune hepatitis; progressive fibrosis slows or is prevented in 79%; and cirrhosis may be reversed. Progressive hepatic fibrosis is associated with liver inflammation, and the inability to fully suppress inflammatory activity within 12 months is associated with progression to cirrhosis (54%) and death or need for liver transplantation (15%). Liver tissue examination remains the gold standard for assessing hepatic fibrosis, but laboratory and radiological tests may be useful non-invasive methods to measure the fibrotic response. Severe liver inflammation can confound radiological assessments, and the preferred non-invasive test in autoimmune hepatitis is uncertain. Individualised treatment adjustments and adjunctive anti-fibrotic therapies are poised for study in this disease.

CONCLUSIONS

The prevention and reversal of hepatic fibrosis are achievable objectives in autoimmune hepatitis. Strategies that evaluate individualised therapies adjusted to the rapidity and completeness of the inflammatory response, and the use of adjunctive anti-fibrotic interventions, must be evaluated.

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.

[Comparison of the M and XL FibroScan(®) probes to estimate liver stiffness by transient elastography]

The FibroScan(®) XL probe has been specifically designed for obese patients to measure liver stiffness by transient elastography, but it has not been well tested in non-obese patients. The aim of this study was to compare the M and XL FibroScan(®) probes in a series of unselected obese (body mass index above 30 kg/m(2)) and non-obese patients with chronic liver disease. Two hundred and fifty-four patients underwent a transient elastography examination with both the M and XL probes. The results obtained with the two probes were compared in the whole series and in obese (n=82) and non-obese (n=167) patients separately. The reliability of the examinations was assessed using the criteria defined by Castéra et al. The proportion of reliable exams was significantly higher when the XL probe was used (83% versus 73%; P=.001). This significance was maintained in the group of obese patients (82% versus 55%; P<.001), but not in the non-obese patients (84% versus 83%). Despite a high correlation between the stiffness values obtained with the two probes (R=.897; P<.001), and a high concordance in the estimation of fibrosis obtained with the two probes (Cronbach's alpha value: 0.932), the liver stiffness values obtained with the XL probe were significantly lower than those obtained with the M probe, both in the whole series (9.5 ± 9.1 kPa versus 11.3 ± 12.6 kPa; P<0.001) and in the obese and non-obese groups. In conclusion, transient elastography with the XL probe allows a higher proportion of reliable examinations in obese patients but not in non-obese patients. Stiffness values were lower with the XL probe than with the M probe.

Multiparametric magnetic resonance for the non-invasive diagnosis of liver disease

BACKGROUND & AIMS

With the increasing prevalence of liver disease worldwide, there is an urgent clinical need for reliable methods to diagnose and stage liver pathology. Liver biopsy, the current gold standard, is invasive and limited by sampling and observer dependent variability. In this study, we aimed to assess the diagnostic accuracy of a novel magnetic resonance protocol for liver tissue characterisation.

METHODS

We conducted a prospective study comparing our magnetic resonance technique against liver biopsy. The individual components of the scanning protocol were T1 mapping, proton spectroscopy and T2* mapping, which quantified liver fibrosis, steatosis and haemosiderosis, respectively. Unselected adult patients referred for liver biopsy as part of their routine care were recruited. Scans performed prior to liver biopsy were analysed by physicians blinded to the histology results. The associations between magnetic resonance and histology variables were assessed. Receiver-operating characteristic analyses were also carried out.

RESULTS

Paired magnetic resonance and biopsy data were obtained in 79 patients. Magnetic resonance measures correlated strongly with histology (r(s)=0.68 p<0.0001 for fibrosis; r(s)=0.89 p<0.001 for steatosis; r(s)=-0.69 p<0.0001 for haemosiderosis). The area under the receiver operating characteristic curve was 0.94, 0.93, and 0.94 for the diagnosis of any degree of fibrosis, steatosis and haemosiderosis respectively.

CONCLUSION

The novel scanning method described here provides high diagnostic accuracy for the assessment of liver fibrosis, steatosis and haemosiderosis and could potentially replace liver biopsy for many indications. This is the first demonstration of a non-invasive test to differentiate early stages of fibrosis from normal liver.

Increased hepatic stiffness as consequence of high hepatic afterload in the Fontan circulation: a vascular Doppler and elastography study

Hepatic dysfunction is a recognized complication after Fontan palliation of congenital heart disease. We sought to quantitatively measure hepatic stiffness and vascular Doppler indices using ultrasound (US) and shear wave elastography (SWE) in a Fontan cohort. Subjects were prospectively recruited for echocardiography and real-time hepatic duplex US with SWE for hepatic stiffness (kPa). Doppler peak velocities, velocity time integral, resistive, pulsatility, acceleration indices (RI, PI, AI), and flow volume were measured in celiac artery, superior mesenteric artery, and main portal vein (MPV). A subset underwent cardiac catheterizations with liver biopsy. Correlations were explored between SWE, duplex, hemodynamic, and histopathologic data. In all, 106 subjects were studied including 41 patients with Fontan physiology (age 13.8 ± 6 years, weight 45.4 ± 23 kg) and 65 controls (age 15.0 ± 8.4 years, weight 47.9 ± 22 kg). Patients with Fontan physiology had significantly higher hepatic stiffness (15.6 versus 5.5 kPa, P < 0.0001), higher celiac RI (0.78 versus 0.73, P = 0.04) superior mesenteric artery RI (0.89 versus 0.84, P = 0.005), and celiac PI (1.87 versus 1.6, P = 0.034); while MPV flow volume (287 versus 420 mL/min in controls, P = 0.007) and SMA AI (829 versus 1100, P = 0.002) were lower. Significant correlation was seen for stiffness with ventricular end-diastolic pressure (P = 0.001) and pulmonary artery wedge pressure (P = 0.009). Greater stiffness correlated with greater degrees of histopathologic fibrosis. No significant change was seen in stiffness or other duplex indices with age, gender, time since Fontan, or ventricular morphology.

CONCLUSION

Elevated hepatic afterload in Fontan, manifested by high ventricular end-diastolic pressures and pulmonary arterial wedge pressures, is associated with remarkably increased hepatic stiffness, abnormal vascular flow patterns, and fibrotic histologic changes. The MPV is dilated and carries decreased flow volume, while the celiac and superior mesenteric arterial RI is increased. SWE is feasible in this population and shows promise as a means for predicting disease severity on liver biopsy.

Outcome analysis of liver stiffness by ARFI (acoustic radiation force impulse) elastometry in patients with chronic viral hepatitis B and C

AIM

To evaluate the association between liver stiffness measured by acoustic radiation force impulse (ARFI) elastometry and the outcome of antiviral treatment in patients with chronic viral hepatitis B and C.

MATERIALS AND METHODS

Thirty-eight patients with chronic viral hepatitis B (n = 16) or hepatitis C (n = 22) underwent liver biopsy and ARFI elastometry of the right hepatic lobe. A follow-up assessment using ARFI was performed a mean of 2.3 years after the baseline evaluation. The patients with favourable outcome were classified in group S and those receiving no treatment, showing no response to treatment, or experiencing a relapse were classified in group N.

RESULTS

The 38 patients had an initial mean ARFI value of 1.56 ± 0.62 m/s as compared with 1.54 ± 0.64 m/s in the follow-up evaluation. Group S showed a significant decline in ARFI values (1.55 ± 0.60 m/s versus 1.34 ± 0.47 m/s; p < 0.05) and included 16 (64%) patients with lower shear wave velocities at follow-up. In group N, liver stiffness values showed a slight but not significant increase (1.57 ± 0.70 m/s versus 1.93 ± 0.77 m/s).

CONCLUSION

Changes in liver stiffness during antiviral therapy can be assessed by ARFI reflecting response or no response. ARFI elastometry is an additional, useful tool for the follow-up assessment of treatment outcome in patients with chronic viral hepatitis B or C infection.

Liver stiffness is associated with risk of decompensation, liver cancer, and death in patients with chronic liver diseases: a systematic review and meta-analysis

BACKGROUND & AIMS

Liver stiffness measurement (LSM), using elastography, can independently predict outcomes of patients with chronic liver diseases (CLDs). However, there is much variation in reporting and consistency of findings. We performed a systematic review and meta-analysis to evaluate the association between LSM and outcomes of patients with CLDs.

METHODS

We performed a systematic review of the literature, through February 2013, for studies that followed up patients with CLDs prospectively for at least 6 months and reported the association between baseline LSM and subsequent development of decompensated cirrhosis or hepatocellular carcinoma (HCC), as well as mortality. Summary relative risk (RR) estimates per unit of LSM and 95% confidence intervals (CIs) were estimated using the random effects model.

RESULTS

Our final analysis included 17 studies, reporting on 7058 patients with CLDs. Baseline LSM was associated significantly with risk of hepatic decompensation (6 studies; RR, 1.07; 95% CI, 1.03-1.11), HCC (9 studies; RR, 1.11; 95% CI, 1.05-1.18), death (5 studies; RR, 1.22; 95% CI, 1.05-1.43), or a composite of these outcomes (7 studies; RR, 1.32; 95% CI, 1.16-1.51). We observed considerable heterogeneity among studies-primarily in the magnitude of effect, rather than the direction of effect. This heterogeneity could not be explained by variations in study locations, etiologies and stages of CLD, techniques to measure liver stiffness, adjustment for covariates, or method of imputing relationship in the meta-analysis.

CONCLUSIONS

Based on a meta-analysis of cohort studies, the degree of liver stiffness is associated with risk of decompensated cirrhosis, HCC, and death in patients with CLDs. LSM therefore might be used in risk stratification.

Entecavir treatment reduces hepatic events and deaths in chronic hepatitis B patients with liver cirrhosis

Entecavir is a potent antiviral agent with high genetic barrier to resistance, hence it is currently recommended as first-line antiviral therapy for chronic hepatitis B (CHB). The aim of this study was to investigate the efficacy of entecavir on clinical outcomes and deaths. It was a retrospective-prospective cohort study based on two cohorts of patients. The entecavir cohort included consecutive CHB patients who had received entecavir 0.5 mg/day for at least 12 months. The historical control cohort included untreated patients recruited since 1997 who underwent routine clinical care. The primary outcome was the 5-year cumulative probability of hepatic events, defined as any cirrhotic complications, hepatocellular carcinoma (HCC), and/or liver-related mortality. A total of 1,446 entecavir-treated patients (72% men; age, 51 ± 12 years; follow-up, 36 ± 13 months) and 424 treatment-naïve patients (65% men; age, 41 ± 13 years; follow-up, 114 ± 31 months) were studied. Overall, there was no difference in hepatic events between the entecavir and control cohorts. Among patients with liver cirrhosis (482 entecavir-treated, 69 treatment-naïve), entecavir-treated patients had reduced risks of all clinical outcomes when compared with treatment-naïve patients with cirrhosis after adjusted for model for end-stage liver disease score: hepatic events (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.34-0.78; P = 0.002), HCC (HR, 0.55; 95% CI, 0.31-0.99; P = 0.049), liver-related mortality (HR, 0.26; 95% CI, 0.13-0.55; P < 0.001), and all-cause mortality (HR, 0.34; 95% CI, 0.18-0.62; P < 0.001). Entecavir-treated patients with cirrhosis who failed to achieve undetectable hepatitis B virus DNA (105/482 [22%]) had comparable risk of hepatic events as the untreated patients.

CONCLUSION

Entecavir therapy reduces the risks of hepatic events, HCC, liver-related and all-cause mortality of CHB patients with liver cirrhosis in 5 years, particularly among those who had maintained viral suppression.

Acoustic radiation force impulse and supersonic shear imaging versus transient elastography for liver fibrosis assessment

Our study compared three elastographic methods--transient elastography (TE), acoustic radiation force impulse (ARFI) imaging and supersonic shear imaging (SSI)--with respect to the feasibility of their use in liver fibrosis evaluation. We also compared the performance of ARFI imaging and SSI, with TE as the reference method. The study included 332 patients, with or without hepatopathies, in which liver stiffness was evaluated using TE, ARFI and SSI. Reliable measurements were defined as a median value of 10 (TE, ARFI imaging) or 5 (SSI) liver stiffness measurements with a success rate ≥60% and an interquartile range interval <30%. A significantly higher percentage of reliable measurements were obtained using ARFI than by using TE and SSI: 92.1% versus 72.2% (p < 0.0001) and 92.1% versus 71.3% (p < 0.0001). Higher body mass index and older age were significantly associated with inability to obtain reliable measurements of liver stiffness using TE and SSI. In 55.4% of patients, reliable liver stiffness measurements were obtained using all three elastographic methods, and ARFI imaging and TE were similarly accurate in diagnosing significant fibrosis and cirrhosis, with TE as the reference method.

The new paradigm of hepatitis C therapy: integration of oral therapies into best practices

Emerging data indicate that all-oral antiviral treatments for chronic hepatitis C virus (HCV) will become a reality in the near future. In replacing interferon-based therapies, all-oral regimens are expected to be more tolerable, more effective, shorter in duration and simpler to administer. Coinciding with new treatment options are novel methodologies for disease screening and staging, which create the possibility of more timely care and treatment. Assessments of histologic damage typically are performed using liver biopsy, yet noninvasive assessments of histologic damage have become the norm in some European countries and are becoming more widespread in the United States. Also in place are new Centers for Disease Control and Prevention (CDC) initiatives to simplify testing, improve provider and patient awareness and expand recommendations for HCV screening beyond risk-based strategies. Issued in 2012, the CDC recommendations aim to increase HCV testing among those with the greatest HCV burden in the United States by recommending one-time testing for all persons born during 1945-1965. In 2013, the United States Preventive Services Task Force adopted similar recommendations for risk-based and birth-cohort-based testing. Taken together, the developments in screening, diagnosis and treatment will likely increase demand for therapy and stimulate a shift in delivery of care related to chronic HCV, with increased involvement of primary care and infectious disease specialists. Yet even in this new era of therapy, barriers to curing patients of HCV will exist. Overcoming such barriers will require novel, integrative strategies and investment of resources at local, regional and national levels.

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.

The influence of aminotransferase levels on liver stiffness assessed by Acoustic Radiation Force Impulse Elastography: a retrospective multicentre study

BACKGROUND

Acoustic Radiation Force Impulse Elastography is a new method for non-invasive evaluation of liver fibrosis.

AIM

To evaluate the impact of elevated alanine aminotransferase levels on liver stiffness assessment by Acoustic Radiation Force Impulse Elastography.

METHODS

A multicentre retrospective study including 1242 patients with chronic liver disease, who underwent liver biopsy and Acoustic Radiation Force Impulse. Transient Elastography was also performed in 512 patients.

RESULTS

The best Acoustic Radiation Force Impulse cut-off for predicting significant fibrosis was 1.29 m/s in cases with normal alanine aminotransferase levels and 1.44 m/s in patients with alanine aminotransferase levels>5 × the upper limit of normal. The best cut-off for predicting liver cirrhosis were 1.59 and 1.75 m/s, respectively. Acoustic Radiation Force Impulse cut-off for predicting significant fibrosis and cirrhosis were relatively similar in patients with normal alanine aminotransferase and in those with alanine aminotransferase levels between 1.1 and 5 × the upper limit of normal: 1.29 m/s vs. 1.36 m/s and 1.59 m/s vs. 1.57 m/s, respectively. For predicting cirrhosis, the Transient Elastography cut-offs were significantly higher in patients with alanine aminotransferase levels between 1.1 and 5 × the upper limit of normal compared to those with normal alanine aminotransferase: 12.3 kPa vs. 9.1 kPa.

CONCLUSION

Liver stiffness values assessed by Acoustic Radiation Force Impulse and Transient Elastography are influenced by high aminotransferase levels. Transient Elastography was also influenced by moderately elevated aminotransferase levels.

Ultrasound elastography for fibrosis surveillance is cost effective in patients with chronic hepatitis C virus in the UK

BACKGROUND

Chronic hepatitis C (HCV) is a significant risk factor for cirrhosis and subsequently hepatocellular carcinoma (HCC). HCV patients with cirrhosis are screened for HCC every 6 months. Surveillance for progression to cirrhosis and consequently access to HCC screening is not standardized. Liver biopsy, the usual test to determine cirrhosis, carries a significant risk of morbidity and associated mortality. Transient ultrasound elastography (fibroscan) is a non-invasive test for cirrhosis.

PURPOSE

This study assesses the cost effectiveness of annual surveillance for cirrhosis in patients with chronic HCV and the effect of replacing biopsy with fibroscan to diagnose cirrhosis.

METHOD

A Markov decision analytic model simulated a hypothetical cohort of 10,000 patients with chronic HCV initially without fibrosis over their lifetime. The cirrhosis surveillance strategies assessed were: no surveillance; current practice; fibroscan in current practice with biopsy to confirm cirrhosis; fibroscan completely replacing biopsy in current practice (definitive); annual biopsy; annual fibroscan with biopsy to confirm cirrhosis; annual definitive fibroscan.

RESULTS

Our results demonstrate that annual definitive fibroscan is the optimal strategy to diagnose cirrhosis. In our study, it diagnosed 20 % more cirrhosis cases than the current strategy, with 549 extra patients per 10,000 accessing screening over a lifetime and, consequently, 76 additional HCC cases diagnosed. The lifetime cost is £98.78 extra per patient compared to the current strategy for 1.72 additional unadjusted life years. Annual fibroscan surveillance of 132 patients results in the diagnosis one additional HCC case over a lifetime. The incremental cost-effectiveness ratio for an annual definitive fibroscan is £6,557.06/quality-adjusted life years gained.

CONCLUSION

Annual definitive fibroscan may be a cost-effective surveillance strategy to identify cirrhosis in patients with chronic HCV, thereby allowing access of these patients to HCC screening.

Meta-analysis: ARFI elastography versus transient elastography for the evaluation of liver fibrosis

AIMS

This meta-analysis aims to compare the diagnostic performance of acoustic radiation force impulse (ARFI) elastography and transient elastography (TE) in the assessment of liver fibrosis using liver biopsy (LB) as 'gold-standard'.

METHODS

PubMed, Medline, Lilacs, Scopus, Ovid, EMBASE, Cochrane and Medscape databases were searched for all studies published until 31 May 2012 that evaluated the liver stiffness by means of ARFI, TE and LB. Information abstracted from each study according to a fixed protocol included study design and methodological characteristics, patient characteristics, interventions, outcomes and missing outcome data.

RESULTS

Thirteen studies (11 full-length articles and 2 abstracts) including 1163 patients with chronic hepatopathies were included in the analysis. Inability to obtain reliable measurements was more than thrice as high for TE as that of ARFI (6.6% vs. 2.1%, P < 0.001). For detection of significant fibrosis, (F ≥ 2) the summary sensitivity (Se) was 0.74 (95% CI: 0.66-0.80) and specificity (Sp) was 0.83 (95% CI: 0.75-0.89) for ARFI, while for TE the Se was 0.78 (95% CI: 0.72-0.83) and Sp was 0.84 (95% CI: 0.75-0.90). For the diagnosis of cirrhosis, the summary Se was 0.87 (95% CI: 0.79-0.92) and Sp was 0.87 (95% CI: 0.81-0.91) for ARFI elastography, and, respectively, 0.89 (95% CI: 0.80-0.94) and 0.87 (95% CI: 0.82-0.91) for TE. The diagnostic odds ratio of ARFI and TE did not differ significantly in the detection of significant fibrosis [mean difference in rDOR = 0.27 (95% CI: 0.69-0.14)] and cirrhosis [mean difference in rDOR = 0.12 (95% CI: 0.29-0.52)].

CONCLUSION

Acoustic radiation force impulse elastography seems to be a good method for assessing liver fibrosis, and shows higher rate of reliable measurements and similar predictive value to TE for significant fibrosis and cirrhosis.

Operator training requirements and diagnostic accuracy of Fibroscan in routine clinical practice

BACKGROUND

Fibroscan is a quick, non-invasive technique used to measure liver stiffness (kPa), which correlates with fibrosis. To achieve a valid liver stiffness evaluation (LSE) the operator must obtain all the following three criteria: (1) ≥10 successful liver stiffness measurements; (2) IQR/median ratio <0.30 and (3) ≥60% measurement success rate.

OBJECTIVES

To assess the operator training requirements and the importance of adhering to the LSE validity criteria in routine clinical practice.

METHODS

We retrospectively analysed the LSE validity rates of 2311 Fibroscans performed (1 August 2008 to 31 July 2011) in our tertiary liver outpatients department at the University Hospital Birmingham, UK. The diagnostic accuracy of Fibroscan was assessed in 153 patients, by comparing LSE (valid and invalid) with the modified Ishak fibrosis stage on liver biopsy.

RESULTS

Learning curve analysis highlighted that the greatest improvement in validity of LSE rates occurs in the operator's first 10 Fibroscans, reaching 64.7% validity by the 50th Fibroscan. The correlation between LSE and the fibrosis stage on liver biopsy was superior in patients with a valid LSE (n=97) compared with those with an invalid LSE (n=56) (rs 0.577 vs 0.259; p=0.022). Area under receiving operating characteristics for significant fibrosis was greater when LSE was valid (0.83 vs 0.66; p=0.048). Using an LSE cut-off of 8 kPa, the negative predictive value of valid LSE was superior to invalid LSE for the detection of significant (84% vs 71%) and advanced fibrosis (100% vs 93%).

CONCLUSIONS

Fibroscan requires minimal operator training (≥10 observed on patients), and when a valid LSE is obtained, it is an accurate tool for excluding advanced liver fibrosis. To ensure the diagnostic accuracy of Fibroscan it is essential that the recommended LSE validity criteria are adhered to in routine clinical practice.

Liver stiffness measurements by means of supersonic shear imaging in patients without known liver pathology

We used supersonic shear imaging to determine the liver stiffness (LS) values of 82 patients without known liver pathology and studied the factors that influence these measurements. Five LS measurements were made in each subject, and the median value, expressed in kilopascals, was calculated. Reliable LS measurements were obtained in 84.5% of patients. Higher body mass index and older age were associated with failure to obtain reliable measurements. The mean value of LS measurements determined by SSI in our cohort of patients without known liver pathology was 6 ± 1.4 kPa. The mean LS measurements determined by SSI for men were significantly higher than those for women; body mass index did not significantly influence SSI measurements. Thus, 6 kPa is the mean SSI value in patients without known liver pathology, with higher values being obtained in men.

The relationship between transient elastography and histological collagen proportionate area for assessing fibrosis in chronic viral hepatitis

BACKGROUND

Collagen proportionate area (CPA) has a better correlation with hepatic venous pressure gradient (HVPG) than with Ishak stage. Liver stiffness measurement (LSM) is proposed as non invasive marker of portal hypertension/disease progression. Our aim was to compare LSM and CPA with Ishak staging in chronic viral hepatitis, and HVPG in HCV hepatitis after transplantation.

METHODS

One hundred and sixty-nine consecutive patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections pre/post liver transplantation (LT), had a liver biopsy combined with LSM (transient elastography), CPA (biopsies stained with Sirius Red and evaluated by digital image analysis and expressed as CPA) and HVPG (measured contemporaneously with transjugular biopsies in LT HCV patients).

RESULTS

LSM was dependent on CPA in HBV (r (2) = 0.61, p < 0.0001), HCV (r (2) = 0.59, p < 0.0001) and LT groups (r (2) = 0.64, p < 0.0001). In all three groups, CPA and Ishak were predictors of LSM, but multivariately CPA was better related to LSM (HBV: r (2) = 0.61, p < 0.0001; HCV: r (2) = 0.59, p < 0.0001; post-LT: r (2) = 0.68, p < 0.0001) than Ishak stage. In the LT group, multiple regression analysis including HVPG, LSM, aspartate aminotransferase to platelet ratio index (APRI) and Ishak stage/grade, showed that only CPA was related to HVPG (r (2) = 0.41, p = 0.01), both for HVPG ≥6 mmHg (OR 1.34, 95 % CI 1.14-1.58; p < 0.0001) or ≥10 mmHg (OR 1.25, 95 % CI 1.06-1.47; p = 0.007).

CONCLUSION

CPA was related to LSM in HBV or HCV hepatitis pre/post-LT. CPA was better related to LSM than Ishak stage. In the LT HCV group, CPA was better related to HVPG than Ishak stage/grade, LSM or APRI. CPA may represent a better comparative histological index for LSM, rather than histological stages.

The role of ultrasound elastographic techniques in chronic liver disease: current status and future perspectives

This review illustrates the state of the art clinical applications and the future perspectives of ultrasound elastographic methods for the evaluation of chronic liver diseases, including the most widely used and validated technique, transient elastography, followed by shear wave elastography and strain imaging elastography. Liver ultrasound elastography allows the non-invasive evaluation of liver stiffness, providing information regarding the stage of fibrosis, comparable to liver biopsy which is still considered the gold standard; in this way, it can help physicians in managing patients, including the decision as to when to start antiviral treatment. The characterization of focal liver lesions and the prognostic role of the elastographic technique in the prediction of complications of cirrhosis are still under investigation.

Management of varices in patients with cirrhosis

Variceal bleeding remains a life-threatening condition with a 6-week mortality rate of ∼20%. Prevention of variceal bleeding can be achieved using nonselective β-blockers (NSBBs) or endoscopic band ligation (EBL), with NSBBs as the first-line treatment. EBL should be reserved for cases of intolerance or contraindications to NSBBs. Although NSBBs cannot be used to prevent varices, if the hepatic venous pressure gradient (HVPG) is ≤10 mmHg, prognosis is excellent. Survival after acute variceal bleeding has improved over the past three decades, but patients with Child-Pugh grade C cirrhosis remain at greatest risk. Vasoactive drugs combined with endoscopic therapy and antibiotics are the best therapeutic strategy for these patients. Transjugular intrahepatic portosystemic shunts (TIPS) should be used in patients with uncontrolled bleeding or those who are likely to have difficult-to-control bleeding. Rebleeding from varices occurs in ∼60% of patients 1-2 years after the initial bleeding episode, with a mortality rate of 30%. Secondary prophylaxis should start at day 6 after initial bleeding using a combination of NSBBs and EBL. TIPS with polytetrafluoroethylene-covered stents are the preferred option in patients who fail combined treatment with NSBBs and EBL. Despite the improvement in patient survival, further studies are needed to direct the management of patients with gastro-oesophageal varices and variceal bleeding.

Natural history of cirrhosis

Significant strides have been made in the last few years in advancing our knowledge of the natural history of cirrhosis. These include (1) a better understanding of prognosis in compensated and decompensated cirrhosis, (2) improved estimates of the natural course of variceal bleeding in patients receiving standard of care therapy, (3) recognition of renal failure and infection as important determinants of mortality in the clinic course, (4) realization of the importance of hepatic venous pressure gradient as a marker of prognosis, progression, and treatment response, and (5) evolution of noninvasive studies of liver stiffness as potential predictors of decompensation. Further studies identifying cirrhotics at highest risk of transitioning from a compensated state to a decompensated state will be important in order to alter the natural history of cirrhosis.

Natural history of cirrhosis

Significant strides have been made in the last few years in advancing our knowledge of the natural history of cirrhosis. These include (1) a better understanding of prognosis in compensated and decompensated cirrhosis, (2) improved estimates of the natural course of variceal bleeding in patients receiving standard of care therapy, (3) recognition of renal failure and infection as important determinants of mortality in the clinic course, (4) realization of the importance of hepatic venous pressure gradient as a marker of prognosis, progression, and treatment response, and (5) evolution of noninvasive studies of liver stiffness as potential predictors of decompensation. Further studies identifying cirrhotics at highest risk of transitioning from a compensated state to a decompensated state will be important in order to alter the natural history of cirrhosis.

Sustained virological response: A milestone in the treatment of chronic hepatitis C

AIM: To evaluate the long-term eradication of hepatitis C virus (HCV) infection and liver-related complications in chronically infected patients that have achieved sustained virological response.

METHODS: One hundred and fifty subjects with chronic hepatitis C (CHC) or cirrhosis and sustained virological response (SVR) between the years of 1989 and 2008 were enrolled in a long-term clinical follow-up study at the Gastrointestinal and Liver Unit of the University Hospital of Naples “Federico II”. At the beginning of the study, the diagnosis of HCV infection was made on the basis of serum positivity for antibodies to HCV and detection of HCV RNA transcripts, while a diagnosis of chronic hepatitis was formulated using imaging techniques and/or a liver biopsy. SVR was achieved by interferon-based therapy, both conventional and pegylated, with and without ribavirin treatment. The patients were evaluated for follow-up at a median length of 8.6 years, but ranged from 2-19.9 years. Among them, 137 patients had pre-treatment CHC and 13 had cirrhosis. The patients were followed with clinical, biochemical, virological, and ultrasound assessments on a given schedule. Finally, a group of 27 patients underwent a liver biopsy at the beginning of the study and transient elastography at their final visit to evaluate changes in liver fibrosis.

RESULTS: The median follow-up was 8.6 years (range 2-19.9 years). HCV RNA remained undetectable in all patients, even in patients who eventually developed liver-related complications, indicating no risk of HCV recurrence. Three liver-related complications were observed: two cases of hepatocellular carcinoma and one case of bleeding from esophageal varices resulting in an incidence rate of 0.23%/person per year. Further, all three complications took place in patients diagnosed with cirrhosis before treatment began. Only one death due to liver-related causes occurred, resulting in a mortality rate of 0.077% person per year. This amounts to a 99.33% survival rate in our cohort of patients after therapy for HCV infection. Finally, of the 27 patients who underwent a liver biopsy at the beginning of the study, a reduction in liver fibrosis was observed in 70.3% of the cases; only three cases registering values of liver stiffness indicative of significant fibrosis.

CONCLUSION: Patients with CHC and SVR show an excellent prognosis with no risk of recurrence and a very low rate of mortality. Our data indicate that virus-eradication following interferon treatment can last up to 20 years.

Factors influencing reliability of liver stiffness measurements using transient elastography (M-probe)-monocentric experience

AIM

To retrospectively assess the feasibility of transient elastography (TE) and the factors associated with failed and unreliable liver stiffness measurements (LSMs), in patients with chronic liver diseases.

MATERIAL AND METHODS

Our retrospective study included 8218 consecutive adult patients with suspected chronic liver diseases. In each patient, LSMs were performed with a FibroScan(®) device (Echosens, France), with the M probe. Failure of TE measurements was defined if no valid measurement was obtained after at least 10 shots and unreliable if fewer than 10 valid shots were obtained, success rate (SR) <60% and/or interquartile range interval/median value (IQR/Med) ≥30%.

RESULTS

From the 8218 patients, failed and unreliable LSMs were observed in 29.2% of cases. In univariant analysis, the following risk factors were associated with failed and unreliable measurements: age over 50 years (OR 2.04; 95%CI 1.84-2.26), female gender (OR 1.32; 95%CI 1.20-1.45), BMI>27.7kg/m(2) (OR 2.89, 95%CI 2.62-3.19), weight>77kg (OR 2.17; 95%CI 1.97-2.40) and height<162cm (OR 1.26; 95%CI 1.14-1.40). In multivariate analysis all the factors mentioned above were independently associated with the risk of failed and unreliable measurements. If all the negative predictive factors were present (woman, older than 50 years, with BMI>27.7kg/m(2), heavier than 77kg and shorter than 162cm), the rate of failed and unreliable measurements was 58.5%. In obese patients (BMI≥30kg/m(2)), the rate of failed and unreliable measurements was 49.5%.

CONCLUSION

Failed and unreliable LSMs were observed in 29.1% of patients. Female gender, older age, higher BMI, higher weight and smaller height were significantly associated with failed and unreliable LSMs.

The influence of food intake on liver stiffness values assessed by acoustic radiation force impulse elastography-preliminary results

The present study assessed the influence of food intake on acoustic radiation force impulse elastography (ARFI) measurements. Seventy-three healthy volunteers were included: 57 subjects in the study group (on whom ARFI measurements were performed first in fasting condition, followed by measurements made 1h and 3h after food intake); and 16 subjects in the control group (on whom ARFI measurements were performed 3 times during a 3-h interval without eating). All subjects included in the study group received the same standard solid meal. In the study group, the mean liver stiffness (LS) values by ARFI increased significantly 1 h after food intake (1.51 ± 0.40 m/s vs. 1.27 ± 0.23, p = 0.003), but 3 h after the meal the differences were no longer significant (1.46 ± 0.51 vs. 1.27 ± 0.23, p = 0.06). In the control group, the mean LS values were similar in all 3 measurements. In conclusion, food intake significantly increased the LS values, thus ARFI measurements should be performed in fasting conditions.

Liver fibrosis in type I Gaucher disease: magnetic resonance imaging, transient elastography and parameters of iron storage

Long term liver-related complications of type-1 Gaucher disease (GD), a lysosomal storage disorder, include fibrosis and an increased incidence of hepatocellular carcinoma. Splenectomy has been implicated as a risk factor for the development of liver pathology in GD. High ferritin concentrations are a feature of GD and iron storage in Gaucher cells has been described, but iron storage in the liver in relation to liver fibrosis has not been studied. Alternatively, iron storage in GD may be the result of iron supplementation therapy or regular blood transfusions in patients with severe cytopenia. In this pilot study, comprising 14 type-1 GD patients (7 splenectomized, 7 non-splenectomized) and 7 healthy controls, we demonstrate that liver stiffness values, measured by Transient Elastography and MR-Elastography, are significantly higher in splenectomized GD patients when compared with non-splenectomized GD patients (p = 0.03 and p = 0.01, respectively). Liver iron concentration was elevated (>60±30 µmol/g) in 4 GD patients of whom 3 were splenectomized. No relationship was found between liver stiffness and liver iron concentration. HFE gene mutations were more frequent in splenectomized (6/7) than in non-splenectomized (2/7) participants (p = 0.10). Liver disease appeared more advanced in splenectomized than in non-splenectomized patients. We hypothesize a relationship with excessive hepatic iron accumulation in splenectomized patients. We recommend that all splenectomized patients, especially those with evidence of substantial liver fibrosis undergo regular screening for HCC, according to current guidelines.

Determination of reliability criteria for liver stiffness evaluation by transient elastography

Liver stiffness evaluation (LSE) is usually considered as reliable when it fulfills all the following criteria: ≥10 valid measurements, ≥60% success rate, and interquartile range / median ratio (IQR/M) ≤0.30. However, such reliable LSE have never been shown to be more accurate than unreliable LSE. Thus, we aimed to evaluate the relevance of the usual definition for LSE reliability, and to improve reliability by using diagnostic accuracy as a primary outcome in a large population. 1,165 patients with chronic liver disease from 19 French centers were included. All patients had liver biopsy and LSE. 75.7% of LSE were reliable according to the usual definition. However, these reliable LSE were not significantly more accurate than unreliable LSE with, respectively: 85.8% versus 81.5% well-classified patients for the diagnosis of cirrhosis (P = 0.082). In multivariate analyses with different diagnostic targets, LSE median and IQR/M were independent predictors of fibrosis staging, with no significant influence of ≥10 valid measurements or LSE success rate. These two reliability criteria determined three LSE groups: "very reliable" (IQR/M ≤0.10), "reliable" (0.10< IQR/M ≤0.30, or IQR/M >0.30 with LSE median <7.1 kPa), and "poorly reliable" (IQR/M >0.30 with LSE median ≥7.1 kPa). The rates of well-classified patients for the diagnosis of cirrhosis were, respectively: 90.4%, 85.8%, and 69.5% (P < 10(-3) ). According to these new reliability criteria, 9.1% of LSE were poorly reliable (versus 24.3% unreliable LSE with the usual definition, P < 10(-3) ), 74.3% were reliable, and 16.6% were very reliable.

CONCLUSION

The usual definition for LSE reliability is not relevant. LSE reliability depends on IQR/M according to liver stiffness median level, defining thus three reliability categories: very reliable, reliable, and poorly reliable LSE. (HEPATOLOGY 2013).

Factors which influence the accuracy of acoustic radiation force impulse (ARFI) elastography for the diagnosis of liver fibrosis in patients with chronic hepatitis C

Our study tried to identify the factors associated with discordance between liver stiffness values assessed by acoustic radiation force impulse (ARFI) elastography and histologic fibrosis in 106 chronic hepatitis C patients. Liver biopsy (LB) and ARFI measurements were performed in the same session. A discordance of at least two stages of fibrosis in the Metavir scoring system between ARFI results and LB was defined as significant. The performance of ARFI elastography was assessed using the following cut-offs: F1-1.19 m/s, F2-1.34 m/s, F3-1.55 m/s and F4-1.80 m/s. Discordance of at least two stages of fibrosis between ARFI results and histologic assessment were observed in 31.7% of the patients. In an univariate analysis, female sex (p = 0.004), interquartile range interval (IQR) ≥30% (p = 0.04), high alanine aminotransferases (p = 0.008) and high aspartate aminotransferases levels (p = 0.003) were associated with discordances. In a multivariate analysis, the female sex (p = 0.006) and IQR ≥30% (p = 0.004) were associated with discordances. Therefore, IQR parameter should be used for ARFI measurements.

Comparative assessment of liver fibrosis by computerized morphometry in naïve patients with chronic hepatitis B and C

BACKGROUND

Liver fibrosis, now assessed by liver biopsy or using non-invasive methods, might be different in chronic hepatitis B (CHB) and chronic hepatitis C (CHC).

AIM

To compare histological amount and pattern of fibrosis in CHB and CHC.

METHODS

Sixty CHB and sixty CHC biopsies from naïve patients, standardized for the spectrum of Metavir fibrosis stages, were analysed for (1) semi-quantitative Metavir activity, steatosis, perisinusoidal fibrosis, alpha-smooth muscle actin immunoreactivity, (2) quantitative morphometry of total and perisinusoidal fibrosis ratio (FR and PFR).

RESULTS

Biopsy quality, activity, steatosis, Fibrotest(®) values were not different between the two groups. Correlation between FR and fibrosis stage was stronger in CHB (r = 0.90) than CHC (r = 0.81). Mean FR was 1.5-fold higher in CHC than CHB for early fibrosis stages (F ≤ 2, P = 0.001), with higher PFR in CHC for F0 (P = 0.001), F1 (P = 0.08) and F2 (P = 0.004). Hepatic stellate cell activation index was also higher in CHC than in CHB (P = 0.007). Diagnosis performance of FR for significant fibrosis was not statistically different in CHB than CHC (AUROC 0.92 and 0.87 respectively), but cut-offs optimizing sensitivity and specificity were higher in CHC and their extrapolation to CHB led to 10% decrease in sensitivity. In F ≤ 2 patients, correlation between FR and Fibrotest(®) was only significant in CHC.

CONCLUSIONS

As compared to CHB, amount of fibrosis is greater in CHC for F ≤ 2 patients, mainly because of higher perisinusoidal fibrosis. These data illustrate difficulty to assess early fibrosis stages by non-invasive methods, and support the need for specific cut-offs in CHB.

Staging of hepatic fibrosis: comparison of magnetic resonance elastography and shear wave elastography in the same individuals

Objective

To cross-validate liver stiffness (LS) measured on shear wave elastography (SWE) and on magnetic resonance elastography (MRE) in the same individuals.

Materials and Methods

We included 94 liver transplantation (LT) recipients and 114 liver donors who underwent either MRE or SWE before surgery or biopsy. We determined the technical success rates and the incidence of unreliable LS measurements (LSM) of SWE and MRE. Among the 69 patients who underwent both MRE and SWE, the median and coefficient of variation (CV) of the LSM from each examination were compared and correlated. Areas under the receiver operating characteristic curve in both examinations were calculated in order to exclude the presence of hepatic fibrosis (HF).

Results

The technical success rates of MRE and SWE were 96.4% and 92.2%, respectively (p = 0.17), and all of the technical failures occurred in LT recipients. SWE showed 13.1% unreliable LSM, whereas MRE showed no such case (p < 0.05). There was moderate correlation in the LSM in both examinations (r = 0.67). SWE showed a significantly larger median LSM and CV than MRE. Both examinations showed similar diagnostic performance for excluding HF (Az; 0.989, 1.000, respectively).

Conclusion

MRE and SWE show moderate correlation in their LSMs, although SWE shows higher incidence of unreliable LSMs in cirrhotic liver.

Course of liver fibrosis in HIV-hepatitis C virus-coinfected patients depending on the response to hepatitis C therapy

To evaluate the course of liver fibrosis, 328 HIV-hepatitis C virus (HCV)-coinfected patients (210 HCV treated and 118 HCV untreated) were followed-up for 38-42 months. Liver fibrosis was assessed by biopsy or elastometry at baseline and by elastometry afterward, in addition to other noninvasive indexes. A combined liver stiffness stage (LSS) was established and evaluated over time. Eighty patients had sustained virological response (SVR) and 130 had treatment failure (TF) after a standard course of peginterferon-ribavirin therapy. LSS decreased significantly in all fibrosis indexes during HCV therapy in treated patients, but the improvement persisted only in those with SVR. At the end of study, median elastometry values suffered variations of -29%, -5.0%, and +15.4% in SVR, TF, and untreated patients, respectively. Likewise, LSS worsened in 2.5%, 33.1%, and 39% of these groups, respectively: [OR (95% CI) 19.3 (4.4-119), p<0.001] for TF vs. SVR; [24.9 (5.6-154), p<0.001] for no therapy vs. SVR; and [1.29 (0.74-2.3), p=0.40] for no therapy vs. TF. LSS improved in 53.8%, 19.2%, and 5.9% of these groups, respectively: [4.88 (2.51-9.53), p<0.001] for SVR vs. TF; 18.4 (7.17-49.4), p<0.001 for SVR vs. no therapy; and 3.78 (1.47-10.1), p=0.003 for TF vs. no therapy. Independent predictive factors of LSS improvement or worsening were as follows: alcohol abuse [OR (95% CI) 0.48 (0.20-0.99), p=0.047] and [2.45 (1.19-5.03), p=0.016], respectively; SVR [27.7 (6.41-168), p<0.001] and [0.15 (0.07-0.31), p<0.001], respectively; and lower baseline CD4 counts [1.92 (1.08-3.45), p=0.026] and [0.31 (0.15-0.63), p=0.001], respectively. SVR was usually associated with regression of noninvasive liver fibrosis markers, whereas TF and HCV-untreated patients experienced poorer outcomes.

The performance of transient elastography compared to clinical acumen and routine tests - what is the incremental diagnostic value?

BACKGROUND/AIMS

There is substantial evidence suggesting transient elastography (TE) is a useful tool in assessing liver fibrosis. We aimed to determine whether TE has incremental diagnostic value over clinical acumen and routinely available tests.

METHODS

We performed a retrospective study of 130 patients to assess the ability of hepatologists to predict severity of fibrosis using clinical acumen; clinical acumen with routine tests; and elastography in patients with chronic liver disease. The incremental diagnostic benefit was assessed using the area under the ROC curve (AUC) and the Net Reclassification Index (NRI).

RESULTS

Using universally available tests, including clinical acumen, the AUCs for detection of cirrhosis ranged from 0.70 to 0.80 for the four hepatologists. Elastography led to statistically non-significant improvements in AUC statistics (range 0.83-0.89; P > 0.01). The detection of significant fibrosis using clinical acumen and routine tests was less accurate, with AUCs of 0.52-0.59. Elastography had incremental diagnostic value (AUC performance range 0.76-0.82; P < 0.01). The NRI indicated that 39-58% were correctly reclassified using elastography, especially with respect to sensitivity.

CONCLUSIONS

Our study suggests that the diagnostic value of clinical acumen and routine tests is acceptable for detection of cirrhosis, but not significant fibrosis. Elastography detects significant fibrosis or cirrhosis with acceptable accuracy and offered incremental diagnostic value in detecting significant fibrosis, but not cirrhosis. These findings have implications for determining the diagnostic value of tests over and above routine clinical assessment, which will aid incorporation of novel tests into clinical algorithms.

Non-invasive measurement of liver and pancreas fibrosis in patients with cystic fibrosis

BACKGROUND

Patients with cystic fibrosis (CF) have a relevant morbidity and mortality caused by CF-related liver-disease. While transient elastography (TE) is an established elastography method in hepatology centers, Acoustic-Radiation-Force-Impulse (ARFI)-Imaging is a novel ultrasound-based elastography method which is integrated in a conventional ultrasound-system. The aim of the present study was to evaluate the prevalence of liver-fibrosis in patients with CF using TE, ARFI-imaging and fibrosis blood tests.

METHODS

106 patients with CF were prospectively included in the present study and received ARFI-imaging of the left and right liver-lobe, ARFI of the pancreas TE of the liver and laboratory evaluation.

RESULTS

The prevalence of liver-fibrosis according to recently published best practice guidelines for CFLD was 22.6%. Prevalence of significant liver-fibrosis assessed by TE, ARFI-right-liver-lobe, ARFI-left-liver-lobe, Fibrotest, Fibrotest-corrected-by-haptoglobin was 17%, 24%, 40%, 7%, and 16%, respectively. The best agreement was found for TE, ARFI-right-liver-lobe and Fibrotest-corrected-by-haptoglobin. Patients with pancreatic-insufficiency had significantly lower pancreas-ARFI-values as compared to patients without.

CONCLUSIONS

ARFI-imaging and TE seem to be promising non-invasive methods for detection of liver-fibrosis in patients with CF.

Performance of liver stiffness measurements by transient elastography in chronic hepatitis

AIM: To compare results of liver stiffness measurements by transient elastography (TE) obtained in our patients population with that used in a recently published meta-analysis.

METHODS: This was a single center cross-sectional study. Consecutive patients with chronic viral hepatitis scheduled for liver biopsy at the outpatient ward of our Infectious Diseases Department were enrolled. TE was carried out by using FibroScan™ (Echosens, Paris, France). Liver biopsy was performed on the same day as TE, as day case procedure. Fibrosis was staged according to the Metavir scoring system. The diagnostic performance of TE was assessed by using receiver operating characteristic (ROC) curves and the area under the ROC curve analysis.

RESULTS: Two hundred and fifty-two patients met the inclusion criteria. Six (2%) patients were excluded due to unreliable TE measurements. Thus, 246 (171 men and 75 women) patients were analyzed. One hundred and ninety-five (79.3%) patients had chronic hepatitis C, 41 (16.7%) had chronic hepatitis B, and 10 (4.0%) were coinfected with human immunodeficiency virus. ROC curve analysis identified optimal cut-off value of TE as high as 6.9 kPa for F≥ 2; 7.9 kPa for F≥ 3; 9.6 kPa for F = 4 in all patients (n = 246), and as high as 6.9 kPa for F≥ 2; 7.3 kPa for F≥ 3; 9.3 kPa for F = 4 in patients with hepatitis C (n = 195). Cut-off values of TE obtained by maximizing only the specificity were as high as 6.9 kPa for F≥ 2; 9.6 kPa for F≥ 3; 12.2 kPa for F = 4 in all patients (n = 246), and as high as 7.0 kPa for F≥ 2; 9.3 kPa for F≥ 3; 12.3 kPa for F = 4 in patients with hepatitis C (n = 195).

CONCLUSION: The cut-off values of TE obtained in this single center study are comparable to that obtained in a recently published meta-analysis that included up to 40 studies.

Transient elastography: a meta-analysis of diagnostic accuracy in evaluation of portal hypertension in chronic liver disease

OBJECTIVES

Transient elastography (TE), as a non-invasive method, has been studied for evaluation of portal hypertension in patients with chronic liver diseases (CLD) with variable results. We studied the performance of TE for detection of significant portal hypertension, oesophageal varices and large oesophageal varices using meta-analysis.

METHODS

PubMed, the Cochrane Library, EMBASE and ISI web of Knowledge were searched. The studies published in English relating to the diagnostic value of TE for significant portal hypertension, oesophageal varices and large oesophageal varices in patients with CLD were collected.

RESULTS

A total of 18 studies, which included 3644 patients were analysed. Summary sensitivity and specificity were 0.90 (95% confidence interval (CI), 0.81-0.95) and 0.79 (95% CI, 0.58-0.91) for significant portal hypertension, and 0.87 (95% CI, 0.80-0.92) and 0.53 (95% CI, 0.36-0.69) for oesophageal varices and 0.86 (95% CI, 0.71-0.94) and 0.59 (95% CI, 0.45-0.72) for large oesophageal varices respectively. The HSROCs were 0.93 for significant portal hypertension, 0.84 for oesophageal varices and 0.78 for large oesophageal varices respectively. TE was very informative with 81% probability of correctly detection significant portal hypertension following a 'positive' measurement (over the threshold value) and lowering the probability of disease to as low as 11% when 'negative' measurement (below the threshold value) when pre-test probability was 50% whereas, for oesophageal varices or large oesophageal varices, the probability of a correct diagnosis following a 'positive' measurement did not exceeded 70%.

CONCLUSIONS

TE could be used as a good screening tool for significant portal hypertension, but only moderate diagnostic utility for the prediction of oesophageal varices or large oesophageal varices.

Accuracy of real-time shear wave elastography for assessing liver fibrosis in chronic hepatitis C: a pilot study

Real-time shear wave elastography (SWE) is a novel, noninvasive method to assess liver fibrosis by measuring liver stiffness. This single-center study was conducted to assess the accuracy of SWE in patients with chronic hepatitis C (CHC), in comparison with transient elastography (TE), by using liver biopsy (LB) as the reference standard. Consecutive patients with CHC scheduled for LB by referring physicians were studied. One hundred and twenty-one patients met inclusion criteria. On the same day, real-time SWE using the ultrasound (US) system, Aixplorer (SuperSonic Imagine S.A., Aix-en-Provence, France), TE using FibroScan (Echosens, Paris, France), and US-assisted LB were consecutively performed. Fibrosis was staged according to the METAVIR scoring system. Analyses of receiver operating characteristic (ROC) curve were performed to calculate optimal area under the ROC curve (AUROC) for F0-F1 versus F2-F4, F0- F2 versus F3-F4, and F0-F3 versus F4 for both real-time SWE and TE. Liver stiffness values increased in parallel with degree of liver fibrosis, both with SWE and TE. AUROCs were 0.92 (95% confidence interval [CI]: 0.85-0.96) for SWE and 0.84 (95% CI: 0.76-0.90) for TE (P = 0.002), 0.98 (95% CI: 0.94-1.00) for SWE and 0.96 (95% CI: 0.90-0.99) for TE (P = 0.14), and 0.98 (95% CI: 0.93-1.00) for SWE and 0.96 (95% CI: 0.91-0.99) for TE (P = 0.48), when comparing F0-F1 versus F2- F4, F0- F2 versus F3-F4, and F0 -F3 versus F4, respectively.

CONCLUSION

The results of this study show that real-time SWE is more accurate than TE in assessing significant fibrosis (≥ F2). With respect to TE, SWE has the advantage of imaging liver stiffness in real time while guided by a B-mode image. Thus, the region of measurement can be guided with both anatomical and tissue stiffness information.

The accuracy of noninvasive methods in the prediction of clinically relevant outcomes in patients with chronic liver disease

The prognosis of chronic liver diseases, which represent a major public health problem, is mainly linked to the extent and progression of liver fibrosis and the subsequent risk of developing cirrhosis and related complications, mainly hepatocellular carcinoma. The article reviewed here reports on the prognostic role of liver stiffness as measured by transient elastography and other noninvasive methods in the prediction of clinical decompensation and hepatocellular carcinoma in patients with chronic hepatitis B. From the results of the study, liver stiffness measurement, as obtained using transient elastography and other noninvasive tests used to assess liver fibrosis, can accurately predict the development of hepatocellular carcinoma and variceal bleeding in patients with chronic hepatitis B.

Sample size requirement for digital image analysis of collagen proportionate area in cirrhotic livers

AIMS

   The requirements for adequate cirrhotic liver biopsy size have not been established for quantitative fibrosis measurements (collagen proportionate area: CPA). We evaluated the CPA of virtual biopsies in cirrhosis to elucidate (i) the amount of tissue required to achieve reliable CPA measurements and (ii) the effect of aetiology on sample size requirements.

METHOD AND RESULTS

   A total of 120 cirrhotic tissue blocks (six aetiologies) were studied. A representative 100 mm(2) region was selected from each block and a reference CPA measured. Each image (n = 120) was divided into 100 × 1 mm(2) images; CPA was measured for each 1 mm(2) and virtual biopsies of different sizes were created from the 1 mm(2) components. For each virtual biopsy size the probability that the virtual biopsy CPA would be within 5% of the reference CPA was calculated. There were 441 000 virtual biopsies. Biopsy size versus probability plots indicated that, for 90% probability that the virtual biopsy CPA can be expected to be within 5% of the reference CPA, 22-28 mm(2) of analysable tissue is required depending on liver disease aetiology; and that a 75% probability level requires a biopsy with 12-15 mm(2) of analysable tissue.

CONCLUSION

   The sample size required for a given probability level depends on the aetiology of cirrhosis, and this should be taken into account when judging the reliability of cirrhotic liver biopsy CPA.

New therapeutic paradigm for patients with cirrhosis

Cirrhosis is a major health problem, being the 5th cause of death in the U.K. and 12th in the U.S., but 4th in the 45 to 54 age group. Until recently cirrhosis was considered a single and terminal disease stage, with an inevitably poor prognosis. However, it is now clear that 1-year mortality can range from 1% in early cirrhosis to 57% in decompensated disease. As the only treatment for advanced cirrhosis is liver transplantation, what is urgently needed is strategies to prevent transition to decompensated stages. The evidence we present in this review clearly demonstrates that management of patients with cirrhosis should change from an expectant algorithm that treats complications as they occur, to preventing the advent of all complications while in the compensated phase. This requires maintaining patients in an asymptomatic phase and not significantly affecting their quality of life with minimal impairment due to the therapies themselves. This could be achieved with lifestyle changes and combinations of already licensed and low-cost drugs, similar to the paradigm of treating risk factors for cardiovascular disease. The drugs are propranolol, simvastatin, norfloxacin, and warfarin, which in combination would cost £128/patient annually-equivalent to U.S. $196/year. This treatment strategy requires randomized controlled trials to establish improvements in outcomes. In the 21st century, cirrhosis should be regarded as a potentially treatable disease with currently available and inexpensive therapies.

CD4⁺ and CD8⁺ regulatory T cells (Tregs) are elevated and display an active phenotype in patients with chronic HCV mono-infection and HIV/HCV co-infection

The aim of this study was to examine regulatory T cells (Tregs) in peripheral blood and liver tissue in patients with chronic hepatitis C virus (HCV) mono-infection and in patients with HIV/HCV co-infection. In a cross-sectional study were included 51 patients with chronic HCV infection, 24 patients with HIV/HCV co-infection and 24 healthy individuals. CD4⁺ and CD8⁺ Tregs were determined using flow cytometry. Fibrosis was examined by transient elastography. Inflammation, fibrosis and Tregs were determined in liver biopsies from 12 patients. Increased frequency of CD4⁺ and CD8⁺ Tregs was found in HIV/HCV co-infected patients [median: 6.4% (IQR: 5.7-6.9) and 1.0% (0.7-1.2), respectively] compared to HCV mono-infected patients [5.6% (4.2-6.3), P = 0.01 and 0.5% (0.3-0.7), P < 0.001, respectively]. Furthermore, HCV mono-infected patients had increased frequencies of Tregs compared with healthy controls (P < 0.05). However, no associations between the frequency of Tregs and fibrosis were found. Furthermore, characterization of CD4⁺ Tregs using CD45RA demonstrated a higher frequency of activated Tregs in both HCV mono-infected and HIV/HCV co-infected patients compared with healthy controls. Finally, number of intrahepatic Tregs was associated with both peripheral CD8⁺ Tregs and intrahepatic inflammation. In conclusion, HCV mono-infected patients and particularly HIV/HCV co-infected patients have increased the frequency of CD4⁺ and CD8⁺ Tregs compared with healthy controls. Furthermore, CD4⁺ Tregs in infected patients displayed an active phenotype. Tregs were not associated with fibrosis, but a positive correlation between intrahepatic Tregs and inflammation was found. Taken together, these results suggest a role for Tregs in the pathogenesis of chronic HCV infection.

Interobserver discrepancy in liver fibrosis using transient elastography

Transient elastography is a useful method to assess liver fibrosis, but uncertainties still exist regarding reliability and reproducibility of the technique. We aimed to improve knowledge on interobserver variability with the procedure and tried to find factors associated with such variability. This was a cross-sectional study to compare the results of transient elastography performed by two different operators, one test made just after the other. We assessed both results with correlation tests and with repeated parametric or nonparametric tests, as needed. We also carried out a multivariate analysis to find factors associated with discrepancy in the results obtained by the two operators. We included a total of 333 pairs of transient elastography tests, belonging to 274 different patients. A total of 325 pairs of tests (97.6%) were valid. Results of the first and the second tests were, respectively, median (and interquartile range) of direct measurement 6.2 (4.6-10.6) and 6.0 (4.4-10.1) kPa (P = 0.012), and mean ± standard deviation of log(10) of direct measurement 0.892 ± 0.316 and 0.871 ± 0.324 (P = 0.001). In 87 pairs of tests (26.7%), a discrepancy of at least 2 kPa between both results was found, and in 15 pairs of tests (4.6%), a discrepancy of at least 10 kPa was found. Discordance of at least one stage between both measurements was noted in 74 pairs of tests (22.8%). An association was found between higher stiffness and discrepancy between both operators (P < 0.001). Although transient elastography is a very convenient test to assess liver fibrosis in clinical practice, interobserver discrepancy in results is common and represents a significant problem with the technique. Discrepant results are more common in patients with higher values of stiffness.

Performance of transient elastography for the staging of liver fibrosis in patients with chronic hepatitis B: a meta-analysis

BACKGROUND

Transient elastography (TE), a non-invasive tool that measures liver stiffness, has been evaluated in meta-analyses for effectiveness in assessing liver fibrosis in European populations with chronic hepatitis C (CHC). However, these data cannot be extrapolated to populations in Asian countries, where chronic hepatitis B (CHB) is more prevalent. In this study, we performed a meta-analysis to assess the overall performance of TE for assessing liver fibrosis in patients with CHB.

METHODS

Studies from the literature and international conference abstracts which enrolled only patients with CHB or performed a subgroup analysis of such patients were enrolled. Combined effects were calculated using area under the receiver operating characteristic curves (AUROC) and diagnostic accuracy values of each study.

RESULT

A total of 18 studies comprising 2,772 patients were analyzed. The mean AUROCs for the diagnosis of significant fibrosis (F2), severe fibrosis (F3), and cirrhosis (F4) were 0.859 (95% confidence interval [CI], 0.857-0.860), 0.887 (95% CI, 0.886-0.887), and 0.929 (95% CI, 0.928-0.929), respectively. The estimated cutoff for F2 was 7.9 (range, 6.1-11.8) kPa, with a sensitivity of 74.3% and specificity of 78.3%. For F3, the cutoff value was determined to be 8.8 (range, 8.1-9.7) kPa, with a sensitivity of 74.0% and specificity of 63.8%. The cutoff value for F4 was 11.7 (range, 7.3-17.5) kPa, with a sensitivity of 84.6% and specificity of 81.5%.

CONCLUSION

TE can be performed with good diagnostic accuracy for quantifying liver fibrosis in patients with CHB.

Acoustic Radiation Force Impulse elastography for fibrosis evaluation in patients with chronic hepatitis C: an international multicenter study

AIM

The aim of this international multicenter study was to evaluate the reliability of Acoustic Radiation Force Impulse (ARFI) elastography for predicting fibrosis severity, in patients with chronic hepatitis C.

PATIENTS AND METHODS

We compared ARFI to liver biopsy (LB) in 914 patients (10 centers, 5 countries) with chronic hepatitis C. In each patient LB (evaluated according to the METAVIR score) and ARFI measurements were performed (median of 5-10 valid measurements, expressed in meters/second - m/s). In 400 from the 914 patients, transient elastography (TE) was also performed (median of 6-10 valid measurements, expressed in kiloPascals - kPa).

RESULTS

Valid ARFI measurements were obtained in 911 (99.6%) of 914 cases. On LB 61 cases (6.7%) had F0, 241 (26.4%) had F1, 202 (22.1%) had F2, 187 (20.4%) had F3, and 223 (24.4%) had F4 fibrosis. A highly significant correlation (r=0.654) was found between ARFI measurements and fibrosis (p<0.0001). The predictive values of ARFI for various stages of fibrosis were: F ≥ 1 - cut-off>1.19 m/s (AUROC=0.779), F ≥ 2 - cut-off>1.33 m/s (AUROC=0.792), F ≥ 3 - cut-off>1.43 m/s (AUROC=0.829), F=4 - cut-off>1.55 m/s (AUROC=0.842). The correlation with histological fibrosis was not significantly different for TE in comparison with ARFI elastography: r=0.728 vs. 0.689, p=0.28. TE was better than ARFI for predicting the presence of liver cirrhosis (p=0.01) and fibrosis (F ≥ 1, METAVIR) (p=0.01).

CONCLUSION

ARFI elastography is a reliable method for predicting fibrosis severity in chronic hepatitis C patients.