Transient elastography and other noninvasive tests to assess hepatic fibrosis in patients with viral hepatitis

Summary. The limitations of liver biopsy (invasive procedure, sampling errors, inter‐observer variability and nondynamic fibrosis evaluation) have stimulated the search for noninvasive approaches for the assessment of liver fibrosis in patients with viral hepatitis. A variety of methods including the measurement of liver stiffness, using transient elastography, and serum markers, ranging from routine laboratory tests to more complex algorithms or indices combining the results of panels of markers, have been proposed. Among serum indices, Fibrotest has been the most extensively studied and validated. Transient elastography appears as a promising method but has been mostly validated in chronic hepatitis C with performance equivalent to that of serum markers for the diagnosis of significant fibrosis. The combination of both approaches as first‐line assessment of liver fibrosis could avoid the performance of liver biopsy in the majority of patients with chronic hepatitis C, a strategy that deserves further evaluation in patients with hepatitis B or HIV‐HCV coinfection. Transient elastography also appears to be an excellent tool for early detection of cirrhosis and may have prognostic value in this setting. Guidelines are now awaited for the use of noninvasive methods in clinical practice.     

Non-invasive assessment of liver fibrosis in chronic liver diseases： Implementation in clinical practice and decisional algorithms

Chronic hepatitis B and C together with alcoholic and non-alcoholic fatty liver diseases represent the major causes of progressive liver disease that can eventually evolve into cirrhosis and its end-stage complications, including decompensation, bleeding and liver cancer. Formation and accumulation of fibrosis in the liver is the common pathway that leads to an evolutive liver disease. Precise definition of liver fibrosis stage is essential for management of the patient in clinical practice since the presence of bridging fibrosis represents a strong indication for antiviral therapy for chronic viral hepatitis, while cirrhosis requires a specific follow-up including screening for esophageal varices and hepatocellular carcinoma. Liver biopsy has always represented the standard of reference for assessment of hepatic fibrosis but it has some limitations being invasive, costly and prone to sampling errors. Recently blood markers and instrumental methods have been proposed for the non-invasive assessment of liver fibrosis. However, there are still some doubts as to their implementation in clinical practice and a real consensus on how and when to use them is not still available. This is due to an unsatisfactory accuracy for some of them,and to an incomplete validation for others. Some studies suggest that performance of non-invasive methods for liver fibrosis assessment may increase when they are combined. Combination algorithms of non-invasive methods for assessing liver fibrosis may represent a rational and reliable approach to implement non-invasive assessment of liver fibrosis in clinical practice and to reduce rather than abolish liver biopsies.     

Physicians’ practices for diagnosing liver fibrosis in chronic liver diseases: A nationwide,Canadian survey

OBJECTIVE:

To determine practices among physicians in Canada for the assessment of liver fibrosis in patients with chronic liver diseases.

METHODS:

Hepatologists, gastroenterologists, infectious diseases specialists, members of the Canadian Gastroenterology Association and/or the Canadian HIV Trials Network who manage patients with liver diseases were invited to participate in a web-based, national survey.

RESULTS:

Of the 237 physicians invited, 104 (43.9%) completed the survey. Routine assessment of liver fibrosis was requested by the surveyed physicians mostly for chronic hepatitis C (76.5%), followed by autoimmune/cholestatic liver disease (59.6%) and chronic hepatitis B (52.9%). Liver biopsy was the main diagnostic tool for 46.2% of the respondents, Fibroscan (Echosens, France) for 39.4% and Fibrotest (LabCorp, USA) for 7.7%. Etiology-specific differences were observed: noninvasive methods were mostly used for hepatitis C (63% versus 37% liver biopsy) and hepatitis B (62.9% versus 37.1% liver biopsy). For 42.7% of respondents, the use of noninvasive methods reduced the need for liver biopsy by >50%. Physicians’ characteristics associated with higher use of noninvasive methods were older age and being based at a university hospital or in private practice versus community hospital. Physicians’ main concerns regarding noninvasive fibrosis assessment methods were access/availability (42.3%), lack of guidelines for clinical use (26.9%) and cost/lack of reimbursement (14.4%).

CONCLUSIONS:

Physicians who manage patients with chronic liver diseases in Canada require routine assessment of liver fibrosis stage. Although biopsy remains the primary diagnostic tool for almost one-half of respondents, noninvasive methods, particularly Fibroscan, have significantly reduced the need for liver biopsy in Canada. Limitations in access to and availability of the noninvasive methods represent a significant barrier. Finally, there is a need for clinical guidelines and a better reimbursement policy to implement noninvasive tools to assess liver fibrosis.     

慢性HBV感染者肝纤维化非创伤性回归模型的研究进展

客观、准确地判断慢性乙型肝炎患者肝纤维化程度有助于选择正确的治疗方案,指导临床治疗。近年来,肝纤维化非创伤性诊断模型不断涌现,然至今尚未取得统一认识。按照肝纤维化不同分期方法,综述了慢性乙型肝炎肝纤维化非创伤性回归模型的研究进展,分析了现有模型存在的问题和不足,认为建立更为简便有效、具有较高诊断价值的诊断模型仍是该领域研究的方向。     

Non-invasive diagnosis of liver fibrosis in chronic hepatitis C

Assessment of liver fibrosis in chronic hepatitis C virus(HCV)infection is considered a relevant part of patient care and key for decision making.Although liver biopsy has been considered the gold standard for staging liver fibrosis,it is an invasive technique and subject to sampling errors and significant intra-and inter-observer variability.Over the last decade,several noninvasive markers were proposed for liver fibrosis diagnosis in chronic HCV infection,with variable performance.Besides the clear advantage of being noninvasive,a more objective interpretation of test results may overcome the mentioned intra-and inter-observer variability of liver biopsy.In addition,these tests can theoretically offer a more accurate view of fibrogenic events occurring in the entire liver with the advantage of providing frequent fibrosis evaluation without additional risk.However,in general,these tests show low accuracy in discriminating between intermediate stages of fibrosis and may be influenced by several hepatic and extrahepatic conditions.These methods are either serum markers(usually combined in a mathematical model)or imaging modalities that can be used separately or combined in algorithms to improve accuracy.In this review we will discuss the different noninvasive methods that are currently available for the evaluation of liver fibrosis in chronic hepatitis C,their advantages,limitations and application in clinical practice.     

Noninvasive diagnosis of liver fibrosis in patients with HIV infection and HCV/HBV co-infection

Summary.  The measurement of fibrosis stage critically affects the identification of the progression of liver disease, the establishment of a prognosis and therapeutic decision making. Liver biopsy has been the single, most useful method to determine the degree of liver fibrosis (LF), but with recognized limitations, mainly associated with its invasiveness. In recent years, alternative noninvasive methods have been developed, including imaging methods, such as transient elastometry, and assays based on serum biomarkers. This article reviews the available studies evaluating the value of various noninvasive methods for the assessment of LF in patients with HIV-infection and HBV/HCV co-infection, and makes recommendations on how to best use and combine them in clinical practice.     

How far is noninvasive assessment of liver fibrosis from replacing liver biopsy in hepatitis C?

Chronic hepatitis C represents a major cause of progressive liver disease that can eventually evolve into cirrhosis and its end-stage complications. Formation and accumulation of fibrosis in the liver is the common pathway that leads to evolutive liver disease. Precise staging of liver fibrosis is essential for patient management in clinical practice because the presence of bridging fibrosis represents a strong indication for antiviral therapy, while cirrhosis requires a specific follow-up. Liver biopsy has always represented the standard of reference for assessment of hepatic fibrosis, but it has limitations: it is invasive, costly and prone to sampling errors. Recently, blood markers and instrumental methods have been proposed for the noninvasive assessment of liver fibrosis in hepatitis C. However, international guidelines do not recommend the widespread use of noninvasive methods for liver fibrosis in clinical practice. This is because of, in some cases, unsatisfactory accuracy and incomplete validation of others. Some studies suggest that the effectiveness of noninvasive methods for assessing liver fibrosis may increase when they are combined, and a number of sequential and synchronous algorithms have been proposed for this purpose, with the aim of reducing rather than substituting liver biopsies. This may represent a rational and reliable approach for implementing noninvasive assessment of liver fibrosis in clinical practice. It could allow more comprehensive first-line screening of liver fibrosis in hepatitis C than would be feasible with liver biopsy alone.     

慢性肝病肝纤维化无创诊断的研究进展

肝活组织检查因其有创性和样本误差,使其临床应用受限,近年来无创诊断与评价肝纤维化成为研究热点之一。介绍了目前主要的血清学模型和FibroScan对肝纤维化诊断的价值,并简述了无创方法的联合应用。现阶段无创诊断方法尚不能完全取代肝活组织检查,不同肝纤维化无创诊断方法对不同病因肝纤维化的诊断价值是否存在差异尚须进一步研究。     

Clinical application of magnetic resonance elastography in chronic liver disease

Recent evidence highlighted that the accurate assessment of liver fibrosis is important for evaluating the progression of chronic liver disease. During the past decade, many non‐invasive methods have been developed to reduce the need for core‐needle biopsy in fibrosis staging and to overcome its limitations, such as invasiveness, high cost, low reproducibility, and poor patient consent. The diagnostic performance of magnetic resonance elastography (MRE) is promising for use in clinical practice to evaluate not only liver fibrosis, but also survival and major clinical end‐points such as liver decompensation, portal hypertension, development of hepatocellular carcinoma, and surgical outcomes. Together with other clinical markers, MRE can be used to better categorize patients with advanced fibrosis and cirrhosis, and assign them to different classes of risk for significant clinical outcomes. This review discusses clinical applications of MRE in the management strategy of patients with chronic liver disease.     

Noninvasive diagnosis of periportal fibrosis in schistosomiasis mansoni: A comprehensive review

Schistosomiasis mansoni is a neglected disease and key public health problem, mainly due to its high prevalence, the scarcity of public policies, and the severity of some clinical forms. Periportal fibrosis (PPF) is the commonest complication of chronic schistosomiasis mansoni and its diagnosis requires different techniques. Even though wedge biopsy of the liver is considered the gold standard, it is not justified in non-surgical patients, and percutaneous liver biopsy may be informative but does not have sufficient sensitivity. Noninvasive PPF tests mostly include biological (serum biomarkers or combined scores) or physical assessments (imaging assessment of fibrosis pattern or tissue stiffness). Moreover, imaging techniques, such as ultrasound, computed tomography, magnetic resonance imaging, and elastography are applied not only to support the diagnosis of schistosomiasis, but also to assess and detect signs of portal hypertension and organ damage due to chronic schistosomiasis. A combination between a comprehensive history and physical examination with biomarkers for liver fibrosis and imaging methods seems to offer the best approach for evaluating these patients. In addition, understanding their strengths and limitations will allow a more accurate interpretation in the clinical context and can lead to greater accuracy in estimating the degree of fibrosis in patients with Schistosomiasis mansoni (S. mansoni) infection. This review will discuss the different noninvasive methods that are currently available for the evaluation of PPF in S. mansoni infection, and their application, advantages, and limitations in clinical practice.     

Role of Noninvasive Fibrosis Methods in Management of Chronic Hepatitis B Virus

Chronic hepatitis B represents a major public health burden. One quarter of patients with chronic hepatitis B will progress to cirrhosis without treatment. According to the current hepatitis B guidelines, treatment is based upon alanine aminotransferase (ALT) elevation and hepatitis B virus (HBV) DNA levels, along with liver fibrosis staging. Liver biopsy still represents the gold standard for the diagnosis and staging of liver fibrosis. However, this method has several limitations like invasiveness, sampling variations, pain, time commitments, and bleeding. In response to this concern, in the last decade, a large amount of noninvasive methods have emerged offering promising diagnostic capabilities. These techniques include serum markers of fibrosis and radiological tests. In the present review, we discuss the performance characteristics and advantages of using noninvasive methods to diagnose and stage liver fibrosis in patients with chronic hepatitis B and its utility in clinical practice.     

Liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfection: Diagnostic methods and clinical impact

Several non-invasive surrogate methods have recently challenged the main role of liver biopsy in assessing liver fibrosis in hepatitis C virus(HCV)-monoinfected and human immunodeficiency virus(HIV)/HCV-coinfected patients, applied to avoid the well-known side effects of liver puncture. Serological tests involve the determination of biochemical markers of synthesis or degradation of fibrosis, tests not readily available in clinical practice, or combinations of routine tests used in chronic hepatitis and HIV/HCV coinfection. Several radiologic techniques have also been proposed, some of which commonly used in clinical practice. The studies performed to compare the prognostic value of noninvasive surrogate methods with that of the degree of liver fibrosis assessed on liver tissue have not as yet provided conclusive results. Each surrogate technique has shown some limitations, including the risk of over- or under-estimating the extent of liver fibrosis. The current knowledge on liver fibrosis in HIV/HCVcoinfected patients will be summarized in this review article, which is addressed in particular to physicians involved in this setting in their clinical practice.     

Elastography in hepatology.

A common characteristic of all chronic liver diseases is the occurrence and progression of fibrosis toward cirrhosis. Consequently, liver fibrosis assessment plays an important role in hepatology. Besides its importance for prognosis, determining the level of fibrosis reveals the natural history of the disease and the risk factors associated with its progression, to guide the antifibrotic action of different treatments. Currently, in clinical practice, there are three available methods for the evaluation of liver fibrosis: liver biopsy, which is still considered to be the 'gold standard'; serological markers of fibrosis and their mathematical combination - suggested in recent years to be an alternative to liver biopsy - and, more recently, transient elastography (TE). TE is a new, simple and noninvasive method used to measure liver stiffness. This technique is based on the progressing speed of an elastic shear wave within the liver. Currently, there are only a few studies that have evaluated TE effectiveness in chronic liver diseases, mostly in patients infected with the hepatitis C virus. Further studies are needed in patients with chronic liver disease, to assess the effectiveness of the fibrosis treatment.     

Checkmate to liver biopsy in chronic hepatitis C?

Liver biopsy (LB) has traditionally been considered the gold standard for pretreatment evaluation of liver fibrosis in patients with chronic hepatitis C (CHC). However, LB is an invasive procedure with several shortcomings (intra- and interobserver variability of histopathological interpretation, sampling errors, high cost) and the risk of rare but potentially life-threatening complications. In addition, LB is poorly accepted by patients and it is not suitable for repeated evaluation. Furthermore, the prevalence of CHC makes LB unrealistic to be performed in all patients with this disease who are candidates for antiviral therapy. The above-mentioned drawbacks of LB have led to the development of noninvasive methods for the assessment of liver fibrosis. Several noninvasive methods, ranging from serum marker assays to advanced imaging techniques, have proved to be excellent tools for the evaluation of liver fibrosis in patients with CHC, whereas the value of LB as a gold standard for staging fibrosis prior to antiviral therapy has become questionable for clinicians. Despite significant resistance from those in favor of LB, noninvasive methods for pretreatment assessment of liver fibrosis in patients with CHC have become part of routine clinical practice. With protease inhibitors-based triple therapy already available and substantial improvement in sustained virological response, the time has come to move forward to noninvasiveness, with no risks for the patient and, thus, no need for LB in the assessment of liver fibrosis in the decision making for antiviral therapy in CHC.     

非酒精性脂肪性肝病的无创性诊断方法

肝活组织检查（LB）是评估非酒精性脂肪性肝病（NAFLD）肝脏病理损伤程度的＂金标准＂,但因其有创性,未能广泛应用于临床。近年来非酒精性脂肪性肝炎（NASH）和进展期肝纤维化无创诊断方法研究进展较快,从临床及生物化学指标、生物标志物、影像学技术方面简述了诊断价值较高的部分无创诊断方法。目前认为NAFLD无创诊断方法尚不能取代LB,但联合应用血清细胞角蛋白18片段和NAFLD纤维化评分、瞬时弹性成像可初步诊断NASH及伴或不伴进展期肝纤维化,并进一步确定LB的使用。     

Clinical application of transient elastography in patients with chronic viral hepatitis receiving antiviral treatment

Accurate evaluation of the degree of liver fibrosis in patients with chronic liver diseases (CLD) is crucial, as liver fibrosis is important in determining the prognosis of liver diseases. Currently, liver biopsy (LB) is considered the gold standard for staging liver fibrosis or cirrhosis. However, utilization of LB in clinical practice is often limited because of its invasive nature, sampling error and interobserver variability. Recently, transient elastography (TE) was introduced as a noninvasive, highly reproducible technique for assessing the degree of liver fibrosis. After extensive studies, TE is now regarded as a reliable surrogate marker for grading the severity of liver fibrosis in patients with CLD. In the past few years, the role of TE in monitoring liver stiffness and determining prognosis in patients with chronic hepatitis B (CHB) or chronic hepatitis C (CHC) who are undergoing antiviral treatment has been investigated. In patients with CHB, liver stiffness values decrease with antiviral treatment. TE can also be used to predict the incidence of liver‐related events during antiviral treatment. In patients with CHC, TE can be used to monitor potential regression of liver fibrosis after antiviral treatment and may predict the treatment outcome of CHC. In addition, TE is an adjunct tool for distinguishing inactive hepatitis B virus carriers from patients with chronic active hepatitis. This review article discusses the important findings from recent studies focusing on the clinical application of TE in patients with chronic viral hepatitis who are undergoing antiviral treatments.     

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

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

Noninvasive evaluation of nonalcoholic fatty liver disease: Current evidence and practice

With the increasing number of individuals with diabetes and obesity,nonalcoholic fatty liver disease(NAFLD) is becoming increasingly prevalent,affecting one-quarter of adults worldwide. The spectrum of NAFLD ranges from simple steatosis or nonalcoholic fatty liver(NAFL) to nonalcoholic steatohepatitis(NASH). NAFLD, especially NASH, may progress to fibrosis, leading to cirrhosis and hepatocellular carcinoma. NAFLD can impose a severe economic burden,and patients with NAFLD-related terminal or deteriorative liver diseases have become one of the main groups receiving liver transplantation. The increasing prevalence of NAFLD and the severe outcomes of NASH make it necessary to use effective methods to identify NAFLD. Although recognized as the gold standard, biopsy is limited by its sampling bias, poor acceptability, and severe complications, such as mortality, bleeding, and pain. Therefore, noninvasive methods are urgently needed to avoid biopsy for diagnosing NAFLD. This review discusses the current noninvasive methods for assessing NAFLD,including steatosis, NASH, and NAFLD-related fibrosis, and explores the advantages and disadvantages of measurement tools. In addition, we analyze potential noninvasive biomarkers for tracking disease processes and monitoring treatment effects, and explore effective algorithms consisting of imaging and nonimaging biomarkers for diagnosing advanced fibrosis and reducing unnecessary biopsies in clinical practice.     

Serum bile acid levels as a predictor for the severity of liver fibrosis in patients with chronic hepatitis C

Summary. Serum bile acids (SBAs) are commonly elevated in cholestatic liver diseases, but it is unclear if SBA levels are also elevated in noncholestatic chronic liver diseases and whether those levels correlate with disease severity. We analysed SBA levels of 135 consecutive patients with chronic hepatitis C virus infection and correlated these levels with the degree of liver fibrosis as determined by liver biopsy. In addition, we assessed the accuracy of SBA levels as a noninvasive predictor for liver fibrosis by its comparison to the patients’ FibroTest scores. Two‐thirds (90/135 patients, 67%) of the study patients had nonsevere liver fibrosis (Metavir F0–F2), and the others (45/135, 33%) had severe fibrosis or cirrhosis (Metavir F3–F4). The SBA levels were significantly higher in patients with severe fibrosis as compared to nonsevere fibrosis (11.46 ± 10.01 vs 6.37 ± 4.69, P < 0.0001). Furthermore, a receiver operator characteristics curve based on a model that included serum bile acids, age, body mass index, serum AST, glucose and cholesterol levels suggested that this combination reliably predicts the degree of liver fibrosis and is not inferior to the current noninvasive FibroTest score (areas under the curve of 0.837 vs 0.83, respectively, P = 0.87). We conclude that measurement of SBA levels may have a clinical role as a simple noninvasive tool to assess the severity of HCV‐induced liver disease. Combined with widely available laboratory parameters, SBA levels can predict disease severity with a high degree of accuracy.     

Clinical applications,limitations and future role of transient elastography in the management of liver disease

Transient elastography(TE) is a reliable tool for the non-invasive assessment of liver fibrosis in routine clinical practice. TE is currently approved for use in Europe, Asia and the United States. The widespread adoption of this technology is certain to increase the use of TE worldwide. Although TE has been well validated in chronic viral hepatitis, its clinical role in other liver diseases remains less clear. The advent of new treatment for chronic hepatitis C and emerging prevalence of non-alcoholic steatohepatitis raises new questions on the role of TE in current clinical practice. This review aims to examine the clinical applications, limitations and future role of TE in current clinical practice in light of the changing epidemiology of liver diseases and new clinical management paradigms. In current clinical practice, TE is the most accurate noninvasive method for diagnosis of liver cirrhosis. TE is useful to rule out fibrosis and cirrhosis but does not have sufficient accuracy to discern between various stages of fibrosis. The clinical role of TE has evolved from cross-sectional point-in-time assessment of fibrosis and cirrhosis to the more relevant role of prediction of vital clinical end-points. This provides clinicians with the ability to modify treatment strategies based on the information provided by TE. TE has evolved over the past decade to become an essential tool to assist the clinician in the management of chronic liver disease.