Baseline values and changes in liver stiffness measured by transient elastography are associated with severity of fibrosis and outcomes of patients with primary sclerosing cholangitis

Risk stratification in autoimmune cholestatic liver diseases: Opportunities for clinicians and trialists

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are infrequent autoimmune cholestatic liver diseases, that disproportionate to their incidence and prevalence, remain very important causes of morbidity and mortality for patients with liver disease. Mechanistic insights spanning genetic risks and biological pathways to liver injury and fibrosis have led to a renewed interest in developing therapies beyond ursodeoxycholic acid that are aimed at both slowing disease course and improving quality of life. International cohort studies have facilitated a much greater understanding of disease heterogeneity, and in so doing highlight the opportunity to provide patients with a more individualized assessment of their risk of progressive liver disease, based on clinical, laboratory, or imaging findings. This has led to a new approach to patient care that focuses on risk stratification (both high and low risk); and furthermore allows such stratification tools to help identify patient subgroups at greatest potential benefit from inclusion in clinical trials. In this article, we review the applicability and validity of risk stratification in autoimmune cholestatic liver disease, highlighting strengths and weaknesses of current and emergent approaches. (Hepatology 2016;63:644-659).

Utility of Noninvasive Markers of Fibrosis in Cholestatic Liver Diseases

Methods of liver fibrosis assessment have changed considerably in the last 20 years, and noninvasive markers now have been recognized as major first-line tools in the management of patients with chronic viral hepatitis infection. But what about the efficiency and utility of these surrogate indices for the more uncommon chronic cholestatic liver diseases, namely primary biliary cirrhosis and primary sclerosing cholangitis? This article provides clinicians with a global overview of what is currently known in the field. Both diagnostic and prognostic aspects of noninvasive markers of fibrosis in cholestatic liver diseases are presented and discussed.

Ultrasound elastography: liver

Ultrasound elastography, also termed sonoelastography, is being used increasingly in clinical practice to aid the diagnosis and management of diffuse liver disease. Elastography has been shown to be capable of differentiating advanced and early-stage liver fibrosis, and consequently a major application in clinical liver care includes progression to cirrhosis risk stratification through (1) assessment of liver fibrosis stage in HCV and HBV patients, (2) distinguishing non-alcoholic steatohepatitis from simple steatosis in non-alcoholic fatty liver disease patients, and (3) prognostic evaluation of liver disease is autoimmune liver disease. In addition, elastographic characterization of focal liver lesions and evaluation of clinically significant portal hypertension have the potential to be clinically useful and are areas of active clinical research.

Progression of liver stiffness predicts clinical events in HIV/HCV-coinfected patients with compensated cirrhosis

Background

Our objective was to assess the predictive value of the changes of liver stiffness (LS) for clinical outcome in HIV/HCV-coinfected patients with compensated liver cirrhosis and a LS value < 40 kPa.

Methods

Prospective cohort of 275 HIV/HCV-coinfected patients with cirrhosis, no previous liver decompensation (LD) and LS < 40 kPa. The time from diagnosis to LD and/or hepatocellular carcinoma (HCC) and the predictors of this outcome were evaluated. Significant progression of LS was defined as an increase ≥ 30 % over the baseline value at any time during the follow-up.

Results

After a median (Q1-Q3) follow-up of 32 (20–48) months, 19 (6.9 %, 95 % CI: 3.8 %–9.9 %) patients developed a first LD and/or HCC. At the end of the follow-up, 247 (90 %) patients had undergone a further LS examination. Of them, 77 (31 %) patients had a significant progression of LS. The mean (SD) survival time free of LD and/or HCC was 67 (3) and 77 (1) months in patients with or without significant progression of LS (p = 0.01). Significant progression of LS was an independent predictor of LD and/or HCC (Adjusted Hazard Ratio 4.63; 95 % confidence interval: 1.34–16.02; p = 0.015).

Conclusions

Significant progression of LS is associated with a higher risk of clinical events in HIV/HCV-coinfected patients with compensated cirrhosis and LS < 40 kPa.

Factors That Could Impact on Liver Fibrosis Staging by Transient Elastography

Transient elastography (TE) based on liver stiffness measurement (LSM) is one of the most validated noninvasive methods for liver fibrosis staging in patients with chronic liver diseases. This method is painless, has no potential complications, is rapid (<10 min), and can be performed at the patient's bedside. However, several points should be considered when interpreting TE results. This review aims to discuss the critical points that might influence liver stiffness and TE results. Spectrum bias and the impact of the prevalence of fibrosis stages should be taken into account when interpreting the studies that validated this method using liver biopsy as a gold-standard. LSM might be influenced by nonfasting status, flare of transaminases, heart failure, extrahepatic cholestasis, presence of steatosis, aetiology of liver disease, type and position of probe, and operator's experience. In addition, interobserver variability can impact on the management of patients with chronic liver diseases. TE should be performed by an experienced operator (>100 exams), in a 3-hour fasting status, and its results should be handled by specialist clinicians that are aware of the limitations of this method.

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.

Contemporary use of elastography in liver fibrosis and portal hypertension

The risk and speed of progression from fibrosis to compensated and decompensated cirrhosis define the prognosis in liver diseases. Therefore, early detection and preventive strategies affect outcomes. Patients with liver disease have traditionally been diagnosed at an advanced stage of disease, in part due to lack of non-invasive markers. Ultrasound elastography to measure liver stiffness can potentially change this paradigm. The purpose of this review was therefore to summarize advances in the field of ultrasound elastography with focus on diagnosis of liver fibrosis, cirrhosis and clinically significant portal hypertension, techniques and limitations. Four types of ultrasound elastography exist, but there is scarce evidence comparing the different techniques. The majority of experience concern transient elastography for diagnosing fibrosis and cirrhosis in patients with chronic viral hepatitis C. That said, the role of elastography in other aetiologies such as alcoholic- and non-alcoholic liver fibrosis still needs clarification. Although elastography can be used to diagnose liver fibrosis and cirrhosis, its true potential lies in the possibility of multiple, repeated measurements that allow for treatment surveillance, continuous risk stratification and monitoring of complications. As such, elastography may be a powerful tool for personalized medicine. While elastography is an exciting technique, the nature of ultrasound imaging limits its applicability, due to the risk of failures and unreliable results. Key factors that limit the applicability of liver stiffness measurements are as follows: liver vein congestion, cholestasis, a recent meal, inflammation, obesity, observer experience and ascites. The coming years will show whether elastography will be widely adapted in general care.

[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.

Hyaluronic acid as a non-invasive biomarker of liver fibrosis

Chronic liver diseases may cause inflammation and progressive scarring, over time leading to irreversible hepatic damage (cirrhosis). As a result, the need to assess and closely monitor individuals for risk factors of components of matrix deposition and degradation, as well as the severity of the fibrosis using biomarkers, has been increasingly recognized.

AIM

Our aim is to review the use of biomarker for diagnosing and defining the severity of liver fibrosis.

METHODS

A systematic literature review was done using the terms "hyaluronic acid" and "liver fibrosis" as well as the name of each biomarker or algorithm known to be employed. PubMed and Google Scholar were searched, and English language articles indexed between January 2010 and October 2014 in which HA was used as a marker of liver fibrosis were retrieved, regardless of the underlying liver disease. Each author read the publications separately and the results were analyzed and discussed.

RESULTS

Biomarkers offer a potential prognostic or diagnostic indicator for disease manifestation, progression, or both. Serum biomarkers, including HA, have been used for many years. Emerging biomarkers such as metalloproteinases have been proposed as tools that provide valuable complementary information to that obtained from traditional biomarkers. Moreover, markers of extracellular matrix degradation provide powerful predictions of risk. In order for biomarkers to be clinically useful in accurately diagnosing and treating disorders, age-specific reference intervals that account for differences in gender and ethnic origin are a necessity.

CONCLUSIONS

This review attempts to provide a comprehensive analysis of the emerging risk biomarkers of liver fibrosis and to describe the clinical significance and analytical considerations of each biomarker pointing out sentinel features of disease progression.

Enhanced liver fibrosis score predicts transplant-free survival in primary sclerosing cholangitis

There is a need to determine biomarkers reflecting disease activity and prognosis in primary sclerosing cholangitis (PSC). We evaluated the prognostic utility of the enhanced liver fibrosis (ELF) score in Norwegian PSC patients. Serum samples were available from 305 well-characterized large-duct PSC patients, 96 ulcerative colitis patients, and 100 healthy controls. The PSC patients constituted a derivation panel (recruited 1992-2006 [n = 167]; median age 41 years, 74% male) and a validation panel (recruited 2008-2012 [n = 138]; median age 40 years, 78% male). We used commercial kits to analyze serum levels of hyaluronic acid, tissue inhibitor of metalloproteinases-1, and propeptide of type III procollagen and calculated ELF scores by the previously published algorithm. Results were also validated by analysis of ELF tests using the ADVIA Centaur XP system and its commercially available reagents. We found that PSC patients stratified by ELF score tertiles exhibited significantly different transplant-free survival in both panels (P < 0.001), with higher scores associated with shorter survival, which was confirmed in the validation panel stratified by ELF test tertiles (P = 0.003). The ELF test distinguished between mild and severe disease defined by clinical outcome (transplantation or death) with an area under the curve of 0.81 (95% confidence interval [CI] 0.73-0.87) and optimal cutoff of 10.6 (sensitivity 70.2%, specificity 79.1%). In multivariate Cox regression analysis in both panels, ELF score (hazard ratio = 1.9, 95% CI 1.4-2.5, and 1.5, 95% CI 1.1-2.1, respectively) was associated with transplant-free survival independently of the Mayo risk score (hazard ratio = 1.3, 95% CI 1.1-1.6, and 1.6, 95% CI 1.2-2.1, respectively). The ELF test correlated with ultrasound elastography in separate assessments.

CONCLUSION

The ELF score is a potent prognostic marker in PSC, independent of the Mayo risk score.

Angiotensin-converting enzyme for noninvasive assessment of liver fibrosis in autoimmune hepatitis

BACKGROUND AND AIM

There are no validated noninvasive markers of liver fibrosis in autoimmune hepatitis (AIH). An activated renin-angiotensin system (RAS) and its key element angiotensin-converting enzyme (ACE) have been implicated in the pathogenesis of hepatic fibrogenesis. We aimed to study the assumed role of activated RAS in the fibrogenic process and whether the serum concentration of ACE can predict different fibrosis stages in AIH.

PATIENTS AND METHODS

Serum samples of 73 consecutive patients who were diagnosed with AIH were analysed for ACE concentration. All patients underwent a liver biopsy.

RESULTS

Serum ACE levels increased significantly for each fibrosis score. The median ACE was 45 U/l in patients with fibrosis score I, 54 U/l in patients with fibrosis score II, 68 U/l in patients with fibrosis score III and 87 U/l in patients with fibrosis score IV. For significant fibrosis (≤F2), a 56 U/l cut-off value of ACE had 95.5% sensitivity and 74.5% specificity, and receiver-operating characteristic curves showed an area under the curve (AUC) of 0.89. For advanced fibrosis (≤F3), a 64 U/l cut-off level of ACE had 85.2% sensitivity and 94.8% specificity, and AUC was 0.91. For cirrhosis, a 68 U/l cut-off level of ACE had 100% sensitivity and 84.4% specificity, and AUC was 0.95.

CONCLUSION

Our results suggest that activated RAS may sustain hepatic fibrogenesis in AIH. Measurement of serum ACE offers an easy, accurate and inexpensive noninvasive method that differentiates significant from nonsignificant liver fibrosis in AIH. Blockade of RAS may exert beneficial effects on fibrosis progression in AIH.

Primary sclerosing cholangitis - the Norwegian experience

Research related to primary sclerosing cholangitis (PSC) has since 1980 been a major activity at the Oslo University Hospital Rikshospitalet. The purpose of this publication is to describe the development of this research, the impact of this research on the clinical handling of the patients, and finally to describe what we believe are the most urgent, remaining problems to be solved. During the early years, our research dealt primarily with clinical aspects of the disease. The concomitant inflammatory bowel disease (IBD) seen in most patients with PSC was a major interest and we also started looking into genetic associations of PSC. Prognosis, malignancy development and treatment with special emphasis on transplantation have later been dealt with. These activities has had impact on several aspects of PSC management; when and how to diagnose PSC and variant forms of PSC, how to handle IBD in PSC and how to deal with the increased rate of malignancy? The problems remaining to be solved are many. What is the role of the gut and the gut microbiota in the development of PSC? Do the PSC patients have an underlying disturbance in the bile homeostasis? And how does the characteristic type of fibrosis in PSC develop? The genetic studies have supported a role for the adaptive immune system in the disease development, but how should this be dealt with? Importantly, the development of malignancy in PSC is still not understood, and we lack appropriate medical treatment for our patients.

Biomarkers for disease progression of primary sclerosing cholangitis

PURPOSE OF REVIEW

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown origin. There is no medical treatment of proven benefit on survival; once patients have progressed to end-stage liver disease, the only treatment option is liver transplantation.

RECENT FINDINGS

Over the last years, some progress has been made in identifying biomarkers of PSC disease progression. Categories that can be distinguished include clinical and biochemical biomarkers, histology, imaging, prognostic modelling and genetics. With this review, we summarize biomarkers for progression of PSC from these six categories, which have been studied to date.

SUMMARY

Biomarkers for the progression of PSC disease course can be used for several purposes. First of all, they can be implemented as surrogate endpoints for clinical trials. Second, biomarkers of disease progression form the basis of prognostic modelling, which is needed for proper patient counselling and management. Lastly, these biomarkers may yield a better understanding of PSC pathogenesis.

Noninvasive assessment of liver function

PURPOSE OF REVIEW

It is our opinion that there is an unmet need in hepatology for a minimally or noninvasive test of liver function and physiology. Quantitative liver function tests define the severity and prognosis of liver disease by measuring the clearance of substrates whose uptake or metabolism is dependent upon liver perfusion or hepatocyte function. Substrates with high-affinity hepatic transporters exhibit high 'first-pass' hepatic extraction and their clearance measures hepatic perfusion. In contrast, substrates metabolized by the liver have low first-pass extraction and their clearance measures specific drug metabolizing pathways.

RECENT FINDINGS

We highlight one quantitative liver function test, the dual cholate test, and introduce the concept of a disease severity index linked to clinical outcome that quantifies the simultaneous processes of hepatocyte uptake, clearance from the systemic circulation, clearance from the portal circulation, and portal-systemic shunting.

SUMMARY

It is our opinion that dual cholate is a relevant test for defining disease severity, monitoring the natural course of disease progression, and quantifying the response to therapy.

Noninvasive methods, including transient elastography, for the detection of liver disease in adults with cystic fibrosis

BACKGROUND

Liver disease is the third leading cause of mortality in patients with cystic fibrosis (CF). However, detection of CF-associated liver disease (CFLD) is challenging.

OBJECTIVE

To evaluate the diagnostic performance of noninvasive methods for the detection of CFLD with a focus on transient elastography (TE).

METHODS

Patients at the Adult CF Clinic of Calgary and Southern Alberta (n=127) underwent liver stiffness measurement (LSM) by TE using the FibroScan (FS, Ecosens, France) M probe; aspartate aminotransferase to platelet ratio index (APRI) and FibroTest (FT) scores were also calculated. The diagnostic performance of these tools for the detection of CFLD (defined as two or more the following criteria: abnormal liver biochemistry, hepatomegaly or sonographic abnormalities other than steatosis) were compared using the area under ROC curves.

RESULTS

Forty-seven percent of the cohort was male. The median age was 27 years (interquartile range [IQR] 22 to 37 years) and body mass index 21 kg⁄m(2) (IQR 19 kg⁄m(2) to 23 kg⁄m(2)); 25% of patients were on ursodeoxycholic acid and 12% had undergone lung transplantation. The prevalence of CFLD was 14% (n=18). FS was successful in all patients; one (0.8%) patient had poorly reliable results (IQR⁄M >30% and LSM ≥7.1 kPa). Compared with patients without CFLD (n=109), individuals with CFLD had higher median LSM according to FS (3.9 kPa [IQR 3.4 to 4.9 kPa] versus 6.4 kPa [IQR 4.4 to 8.0 kPa]), APRI (0.24 [IQR 0.17 to 0.31] versus 0.50 [IQR 0.22 to 1.18]) and FT scores (0.08 [IQR 0.05 to 1.5] versus 0.18 [IQR 0.11 to 0.35]; all P<0.05). Area under ROC curve for FS, APRI and FT for the detection of CFLD were 0.78 (95% CI 0.65 to 0.92), 0.72 (95% CI 0.56 to 0.87) and 0.76 (95% CI 0.62 to 0.90) (P not significant). At a threshold of >5.2 kPa, the sensitivity, specificity, positive and negative predictive values of LSM according to FS for detecting CFLD were 67%, 83%, 40% and 94%, respectively.

CONCLUSIONS

FS, APRI and FT were useful noninvasive methods for detecting CFLD in adults.

Contemporary assessment of hepatic fibrosis

Newer noninvasive tests have begun to replace liver biopsy for staging purposes. The clinician must evaluate these tools and apply them to individual patients. None of these modalities give the exact same staging of fibrosis as a liver biopsy, but they are excellent tools for risk stratification. Still, it should be recognized that there are disease-specific issues with different utilizations and cutoffs for different clinical diseases. This article provides a framework for incorporating the use of serum biomarkers and elastography-based approaches to stage fibrosis into clinical practice. This review also covers recent developments in this rapidly advancing area.

Unmet clinical need in autoimmune liver diseases

Despite recent advances in understanding and treatment, there remain significant areas of unmet clinical need in each of the autoimmune liver diseases (AILDs). The evolving research landscape and emerging large patient cohorts are creating unique opportunities to translate science into new therapies and care pathways, with the potential to significantly improve the lives of AILD patients. However, the areas of unmet need represent real challenges, which need to be addressed, if this vision is to be realised. This review describes the areas of unmet need in AILD in adults relating to diagnostic and prognostic assessment, primary therapy, symptom management, trial design and delivery, and structured care delivery, with the aim of focusing future research prioritisation.

Noninvasive assessment of portal hypertension in cirrhosis: Liver stiffness and beyond

Liver stiffness measurement (LSM) is a good, but still limited tool to noninvasively assess complications and prognosis in patients with advanced liver disease. This review aims to consider the role of LSM for the diagnosis of portal hypertension-related complications and for assessment of prognosis in cirrhotic patients, and to highlight the drawbacks as well as some alternatives for improving the performance. Hence, this field is far from being closed, and deserves more attention. There is still a place for more carefully designed studies to find new, innovative and reliable approaches.

Low risk of hepatocellular carcinoma in patients with primary sclerosing cholangitis with cirrhosis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is associated with an increased risk of hepatobiliary malignancies. However, little is known about the incidence of hepatocellular carcinoma (HCC) among patients with PSC; current recommendations on screening these patients for HCC are conflicting. We investigated the risk of HCC in patients with PSC with cirrhosis.

METHODS

We performed a retrospective study of patients with well-defined PSC from 2 large-volume tertiary care centers in Germany; data were collected from periods of up to 33 years. Liver cirrhosis was based on histology results or the presence of ascites, esophageal varices, or transient elastography values greater than 14 kPa. Statistical analysis was performed using the Kaplan-Meier method and the Cox proportional hazard model. Data from 509 patients (67% male), with a total of 4202 patients-years, were included in the final analysis.

RESULTS

We identified 119 patients with cirrhosis. During 292 patient-years, none of these patients developed HCC. Most HCCs were identified incidentally at the time of liver transplantation. We therefore reviewed data on liver explants from 140 patients who underwent transplantation; none were found to contain HCC. In contrast to the low numbers of HCCs among patients with PSC, 35 patients developed cholangiocarcinoma, 3 patients developed gallbladder cancer, and 9 patients developed colorectal cancer.

CONCLUSIONS

Based on a retrospective analysis of more than 500 patients with PSC, we confirm their high risk for hepatobiliary malignancies. However, the risk of HCC, even among patients with cirrhosis, seems to be low--regular HCC surveillance may not be warranted.

The clinical utility of FibroScan(®) as a noninvasive diagnostic test for liver disease

An important aspect of managing chronic liver disease is assessing for evidence of fibrosis. Historically, this has been accomplished using liver biopsy, which is an invasive procedure associated with risk for complications and significant sampling and observer error, limiting the accuracy for determination of fibrosis stage. Hence, several serum biomarkers and imaging methods for noninvasive assessment of liver fibrosis have been developed. In this article, we review the current literature on an important noninvasive imaging modality to measure tissue elastography (FibroScan^®). This ultrasound-based technique is now increasingly available in many countries and has been shown to be a reliable and safe noninvasive means of assessing disease severity in chronic liver disease of varying etiology.