Hyaluronic acid, an accurate serum marker for severe hepatic fibrosis in patients with non-alcoholic fatty liver disease

Non-invasive screening of diabetics in primary care for NAFLD and advanced fibrosis by MRI and MRE

BACKGROUND

Current guidelines do not recommend screening for non-alcoholic fatty liver disease (NAFLD) or advanced fibrosis. Patients with type 2 diabetes mellitus (T2DM) are known to be at increased risk for NAFLD and advanced fibrosis.

AIM

To assess the feasibility in diabetics in a primary care setting of screening for NAFLD and advanced fibrosis, by using non-invasive magnetic resonance imaging (MRI) to estimate the hepatic proton density fat fraction (MRI-PDFF) and magnetic resonance elastography (MRE) to estimate hepatic stiffness.

METHODS

We performed a cross-sectional analysis of a prospective study that included 100 (53% men) consecutively enrolled diabetics who did not have any other aetiology of liver disease. All patients underwent a standardised research visit, laboratory tests, MRI-PDFF, and MRE.

RESULTS

Mean (±s.d.) age and body mass index (BMI) was 59.7 (±11.2) years and 30.8 (±6.5) kg/m(2) , respectively. The prevalence of NAFLD (defined as MRI-PDFF ≥5%) and advanced fibrosis (defined as MRE ≥3.6 kPa) was 65% and 7.1%, respectively. One patient with advanced fibrosis had definite hepatocellular carcinoma. When compared to those without NAFLD, patients with NAFLD were younger (P = 0.028) and had higher mean BMI (P = 0.0008), waist circumference (P < 0.0001) and prevalence of metabolic syndrome (84.6% vs. 40.0%, P < 0.0001). Only 26% of those with NAFLD had elevated alanine aminotransferase.

CONCLUSIONS

This proof-of-concept study demonstrates that T2DM has significant rates of both NAFLD and advanced fibrosis. Concomitant screening for NAFLD and advanced fibrosis by using MRI-proton density fat fraction and magnetic resonance elastography in T2DM is feasible and may be considered after validation in a larger cohort.

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

BACKGROUND

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

OBJECTIVE

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

DATA SOURCES

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

METHODS

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

RESULTS

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

LIMITATIONS

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

CONCLUSIONS

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

STUDY REGISTRATION

This study is registered as PROSPERO CRD42011001561.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

ZJU index: a novel model for predicting nonalcoholic fatty liver disease in a Chinese population

Non-alcoholic fatty liver disease (NAFLD) is an important health issue worldwide. We aimed to develop a simple model to determine the presence of NAFLD in a Chinese population. A cross-sectional study with 9602 subjects was conducted. Potential predictors were entered into a stepwise logistic regression analysis to obtain the model. We used 148 patients with liver biopsy to validate this model. The model, named the ZJU index, was developed based on body mass index (BMI), fasting plasma glucose (FPG), triglycerides (TG), and the serum alanine aminotransferase (ALT) to serum aspartate transaminase (AST) ratio. The area under the receiver operating characteristic curve (AUROC) of the ZJU index to detect NAFLD was 0.822. At a value of <32.0, the ZJU index could rule out NAFLD with a sensitivity of 92.2%, and at a value of >38.0, the ZJU index could detect NAFLD with a specificity of 93.4%. In patients with liver biopsy, the ZJU index could detect steatosis with good accuracy, with an AUROC of 0.896. This study revealed that the ZJU index is a helpful model to detect NAFLD for community physicians in China. It was validated not only by a validation cohort but also by pathological data.

Association between Wisteria floribunda agglutinin-positive Mac-2 binding protein and the fibrosis stage of non-alcoholic fatty liver disease

BACKGROUND

Accurately evaluating liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) is important for identifying those who may develop complications. The aims of this study were (1) to measure serum Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA(+)-M2BP) using the glycan sugar chain-based immunoassay and (2) to compare the results with clinical assessments of fibrosis.

METHODS

Serum WFA(+)-M2BP values were retrospectively evaluated in 289 patients with NAFLD who had undergone liver biopsy. Histological findings were evaluated by three blinded, experienced liver-specific pathologists.

RESULTS

For stages 0 (n = 35), 1 (n = 113), 2 (n = 49), 3 (n = 41), and 4 (n = 51) of liver fibrosis, the serum WFA(+)-M2BP cutoff indexes were 0.57, 0.70, 1.02, 1.57, and 2.96, respectively. Multivariate regression analysis showed that serum WFA(+)-M2BP values were associated with the stage of fibrosis (≥stage 2). The areas under the receiver operating characteristic curve (AUROC), sensitivity, and specificity of serum WFA(+)-M2BP were 0.876, 85.9, and 74.6%, respectively, for severe fibrosis (≥stage 3) and were 0.879, 74.6, and 87.0%, respectively, for cirrhosis. When compared with six non-invasive conventional markers, serum WFA(+)-M2BP had the greatest AUROC for diagnosing severe fibrosis and cirrhosis.

CONCLUSIONS

Serum WFA(+)-M2BP values are useful for assessing the stage of liver fibrosis in patients with NAFLD.

Liver fibrosis markers of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is one of the major causes of chronic liver injury. NAFLD includes a wide range of clinical conditions from simple steatosis to nonalcoholic steatohepatitis (NASH), advanced fibrosis, and liver cirrhosis. The histological findings of NASH indicate hepatic steatosis and inflammation with characteristic hepatocyte injury (e.g., ballooning degeneration), as is observed in the patients with alcoholic liver disease. NASH is considered to be a potentially health-threatening disease that can progress to cirrhosis. A liver biopsy remains the most reliable diagnostic method to appropriately diagnose NASH, evaluate the severity of liver fibrosis, and determine the prognosis and optimal treatment. However, this invasive technique is associated with several limitations in routine use, and a number of biomarkers have been developed in order to predict the degree of liver fibrosis. In the present article, we review the current status of noninvasive biomarkers available to estimate liver fibrosis in the patients with NASH. We also discuss our recent findings on the use of the glycated albumin-to-glycated hemoglobin ratio, which is a new index that correlates to various chronic liver diseases, including NASH.

Value of reelin for assessing hepatic fibrogenesis in a group of Egyptian HCV infected patients

BACKGROUND

Development of non-invasive markers that can predict the stages of hepatic fibrosis without resorting to repeated liver biopsies is still an important goal to evaluate the effectiveness of antifibrotic treatment. The present work investigates the value of the assessment of peripheral circulating reelin, in which the liver represents its prime source, as a marker for monitoring hepatic fibrogenesis.

METHODS

Seventy-four cases with chronic hepatitis positive for serum HCV RNA and 15 healthy volunteers were enrolled in this study. Assessment of reelin in the harvested serum and in 64 corresponding liver biopsies using immunofluorescence technique was done. The results were evaluated in relation to the stages and quantitative morphometric analysis of hepatic fibrosis as well as the serum levels of the validated biomarker hyaluronic acid.

RESULTS

Significant correlation was detected between the levels of serum reelin and the semiquantitative assessment of reelin immunoreactivity in liver tissue, the stages of hepatic fibrosis, the morphometrically determined collagen and serum hyaluronic acid with a correlation coefficient of 0.675, 0.623, 0.479, 0.772, respectively with p<0.001. The sensitivity and the specificity of reelin for the determination of advanced (F2+F3) and significant fibrosis (F2-F4) were nearly comparable to the result of hyaluronic acid. In addition the area under curve (AUC) were 0.859, 0.871 for the reelin versus 0.878, and 0.891 for the hyaluronic acid.

CONCLUSIONS

In conclusion serum reelin may be considered an additional useful parameter for monitoring the progression of hepatic fibrosis in HCV-infected patients specially in those with active rheumatological conditions which result in an increase in serum hyaluronic acid.

Republished: Non-alcoholic fatty liver disease: non-invasive investigation and risk stratification

Non-alcoholic fatty liver disease (NAFLD) encompasses a histological spectrum of liver disease, from simple steatosis through to cirrhosis. As the worldwide rates of obesity have increased, NAFLD has become the commonest cause of liver disease in many developed countries, affecting up to a third of the population. The majority of patients have simple steatosis that carries a relatively benign prognosis. However, a significant minority have non-alcoholic steatohepatitis, and have increased liver related and cardiovascular mortality. Identifying those at risk of progressive disease is crucial. Liver biopsy remains the gold standard investigation for assessing stage of disease but its invasive nature makes it impractical for widespread use as a prognostic tool. Non-invasive tools for diagnosis and disease staging are required, reserving liver biopsy for those patients where it offers clinically relevant additional information. This review discusses the non-invasive modalities available for assessing steatosis, steatohepatitis and fibrosis. We propose a pragmatic approach for the assessment of patients with NAFLD to identify those at high risk of progressive disease who require referral to specialist services.

Non-invasive diagnosis of advanced fibrosis and cirrhosis

Liver cirrhosis is a common and growing public health problem globally. The diagnosis of cirrhosis portends an increased risk of morbidity and mortality. Liver biopsy is considered the gold standard for diagnosis of cirrhosis and staging of fibrosis. However, despite its universal use, liver biopsy is an invasive and inaccurate gold standard with numerous drawbacks. In order to overcome the limitations of liver biopsy, a number of non-invasive techniques have been investigated for the assessment of cirrhosis. This review will focus on currently available non-invasive markers of cirrhosis. The evidence behind the use of these markers will be highlighted, along with an assessment of diagnostic accuracy and performance characteristics of each test. Non-invasive markers of cirrhosis can be radiologic or serum-based. Radiologic techniques based on ultrasound, magnetic resonance imaging and elastography have been used to assess liver fibrosis. Serum-based biomarkers of cirrhosis have also been developed. These are broadly classified into indirect and direct markers. Indirect biomarkers reflect liver function, which may decline with the onset of cirrhosis. Direct biomarkers, reflect extracellular matrix turnover, and include molecules involved in hepatic fibrogenesis. On the whole, radiologic and serum markers of fibrosis correlate well with biopsy scores, especially when excluding cirrhosis or excluding fibrosis. This feature is certainly clinically useful, and avoids liver biopsy in many cases.

Use of non-invasive parameters of non-alcoholic steatohepatitis and liver fibrosis in daily practice--an exploratory case-control study

Background

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of a metabolic syndrome. To date, liver biopsy has been the gold standard used to differentiate between simple steatosis and steatohepatitis/fibrosis. Our aim was to compare the relevance of serum non-invasive parameters and scoring systems in the staging of liver fibrosis and non-alcoholic steatohepatitis (NASH) in patients with NAFLD.

Methods and Findings

A total of 112 consecutive patients diagnosed with NAFLD were included. A liver biopsy was performed on 56 patients. The Kleiner score was used for the staging and grading of the histology. Non-invasive parameters for fibrosis (hyaluronic acid; AST/ALT; fibrosis scoring indexes OELF, ELF, BARD score, APRI, NAFLD fibrosis score); and inflammation (M30 and M65 cytokeratin-18 fragments) were measured and calculated. The same analyses were performed in 56 patients diagnosed with NAFLD, who were not indicated for liver biopsy. Based on the liver histology, NASH was diagnosed in 38 patients; simple steatosis in 18 patients. A cut-off value of 750 U/L of serum M65 discriminated patients with and without NASH with a 80% sensitivity and 82% specificity (95% CI:57–95). Fibrosis stage F0–F2 was present in 39 patients; F3–F4 in 17 patients. Serum concentrations of hyaluronic acid were higher in patients with advanced fibrosis (p<0.01); a cut-off value of 25 µg/l discriminated patients with F3–F4 with a 90% sensitivity and 84% specificity from those with F0–F2 (95% CI:59–99). When applying the non-invasive criteria to those patients without a liver biopsy, NASH could only be diagnosed in 16%; however, advanced fibrosis could be diagnosed in 35% of them.

Conclusions

In patients with NAFLD, non-invasive serum parameters with a high accuracy can differentiate those patients with NASH and/or advanced fibrosis from those with simple steatosis. A substantial portion of those patients not indicated for liver biopsy might have undiagnosed advanced fibrosis.

Long-term effects of growth hormone replacement therapy on liver function in adult patients with growth hormone deficiency

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are frequently observed in patients with adult growth hormone deficiency (AGHD) and short-term GH replacement therapy (GHRT) has reportedly been efficacious in NAFLD and NASH. The aim of this study was to investigate whether long-term GHRT is an effective treatment for the hepatic comorbidities in AGHD.

DESIGN

This is a retrospective observational study. We recruited 54 consecutive hypopituitary patients with AGHD. Among them, 31 patients who had received GHRT for more than 24 months were compared with 19 age- and sex-matched patients without GHRT. We also analyzed the long term effect of GHRT on 14 patients diagnosed with NASH by liver biopsy. In addition, we subdivided the GHRT group into GH-responder and GH-non-responder groups and analyzed the factors associated with the efficacy of the treatment.

RESULTS

For a period of 24 months, the significant reduction of serum liver enzyme levels and a fibrotic marker was observed in patients receiving GHRT compared with the control group. Furthermore, GHRT also improved liver enzyme levels in AGHD patients with NASH. The GH-non-responder group showed a higher proportion of patients who gained weight during the study period.

CONCLUSIONS

These results indicate that GHRT is efficacious for improving serum liver enzyme levels for at least 24 months in patients with AGHD. To optimize this effect, it is important to avoid body weight gain during the treatment.

Noninvasive biomarkers in non-alcoholic fatty liver disease: Current status and a glimpse of the future

The development of non invasive biomarkers of disease has become a major focus of interest in nonalcoholic fatty liver disease (NAFLD). The large prevalence of the disease and the invasive nature of the investigation means that screening with liver biopsy is impractical. In addition to screening, the differentiation of those with simple steatosis vs steatohepatitis and fibrosis is clinically important as the prognosis of each differs. Serum biomarkers may be a combination of simple markers derived from large data sets or direct markers of disease activity. Serum markers of inflammation, apoptosis and oxidative stress in addition to fibrosis have been extensively studied in patients with NAFLD. Other techniques such as transient elastography, magnetic resonance elastography and acoustic radiation force imaging are becoming more established as noninvasive methods of detecting fibrosis in a variety of chronic liver conditions in addition to NAFLD. Newer high throughput methods such as proteomics and glycomics allow the nonhypothesis-driven identification of novel markers and may also potentially contribute to our understanding of the pathogenesis of the condition. This review addresses some of the methodological issues which need to be considered in the search for the ideal biomarker. It is likely that a combination of serum biomarkers and techniques such as transient elastography may provide the optimal diagnostic discrimination however this remains to be proven in large studies.

Proteomic and genomic studies of non-alcoholic fatty liver disease - clues in the pathogenesis

Non-alcoholic fatty liver disease (NAFLD) is a widely prevalent hepatic disorder that covers wide spectrum of liver pathology. NAFLD is strongly associated with liver inflammation, metabolic hyperlipidaemia and insulin resistance. Frequently, NAFLD has been considered as the hepatic manifestation of metabolic syndrome. The pathophysiology of NAFLD has not been fully elucidated. Some patients can remain in the stage of simple steatosis, which generally is a benign condition; whereas others can develop liver inflammation and progress into non-alcoholic steatohepatitis, fibrosis, cirrhosis and hepatocellular carcinoma. The mechanism behind the progression is still not fully understood. Much ongoing proteomic researches have focused on discovering the unbiased circulating biochemical markers to allow early detection and treatment of NAFLD. Comprehensive genomic studies have also begun to provide new insights into the gene polymorphism to understand patient-disease variations. Therefore, NAFLD is considered a complex and mutifactorial disease phenotype resulting from environmental exposures acting on a susceptible polygenic background. This paper reviewed the current status of proteomic and genomic studies that have contributed to the understanding of NAFLD pathogenesis. For proteomics section, this review highlighted functional proteins that involved in: (1) transportation; (2) metabolic pathway; (3) acute phase reaction; (4) anti-inflammatory; (5) extracellular matrix; and (6) immune system. In the genomic studies, this review will discuss genes which involved in: (1) lipolysis; (2) adipokines; and (3) cytokines production.

Biomarkers of liver fibrosis

Liver fibrosis is the final common pathway for almost all causes of chronic liver injury. Liver fibrosis is now known to be a dynamic process having significant potential for resolution. Therefore, fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. As such, there is strong demand for reliable liver biomarkers that provide insight into disease etiology, diagnosis, therapy, and prognosis in lieu of more invasive approaches such as liver biopsy. Current diagnostic strategies range from use of serum biomarkers to more advanced imaging techniques including transient elastography and magnetic resonance imaging. In addition to these modalities, there are other approaches including the use of novel, but yet to be validated, biomarkers. In this chapter, we discuss the biomarkers of liver fibrosis including the use of invasive and noninvasive biomarkers and disease-specific biomarkers in various chronic liver diseases.

Noninvasive Biomarkers of Liver Fibrosis: An Overview

Chronic liver diseases of differing etiologies are among the leading causes of mortality and morbidity worldwide. Establishing accurate staging of liver disease is very important for enabling both therapeutic decisions and prognostic evaluations. A liver biopsy is considered the gold standard for assessing the stage of hepatic fibrosis, but it has many limitations. During the last decade, several noninvasive markers for assessing the stage of hepatic fibrosis have been developed. Some have been well validated and are comparable to liver biopsy. This paper will focus on the various noninvasive biochemical markers used to stage liver fibrosis.

Hyaluronic Acid: from biochemical characteristics to its clinical translation in assessment of liver fibrosis

CONTEXT

Hyaluronic acid (HA) is a high molecular weight polysaccharide that is distributed in all bodily tissues and fluids. The liver is the most important organ involved in the synthesis and degradation of HA. Research has shown that liver cell injury can affect serum HA levels. In this review, authors aimed to describe the biochemical and physiological roles of this glycosaminoglycan and its changes in various liver diseases.

EVIDENCE ACQUISITION

Liver fibrosis and in more severe form, cirrhosis are results of an imbalance between fibrogenesis and fibrinolysis. Liver biopsy is the gold standard to assess liver necro inflammatory injuries. This method is invasive and has some major side effects; therefore it is an unfavorable method for both physicians and patients. Now, a wide variety of noninvasive methods have been introduced based on evaluating serum level of different markers. They are safe, readily available, and more favorable. Serum HA levels are used by some researchers to assess stages of liver fibrosis.

RESULTS

There are several scientific studies indicating HA as a biomarker for high score fibrosis and cirrhosis in various liver diseases alone or in algorithm models. It seems from various algorithm models that the use of HA as a major constituent has more diagnostic reliability and accuracy than the use of HA alone.

CONCLUSIONS

Use of HA in an algorithm model, is an extra and valuable tool for assessing liver necro inflammatory injuries- in parallel with liver biopsy- but more comprehensive studies are needed to approve the use of HA as an appropriate clinical tool.

Noninvasive evaluation of NAFLD

A common clinical concern in patients with NAFLD is whether they have NASH or simple steatosis and, more importantly, what the stage of fibrosis is and whether the level of fibrosis has increased over time. Such concern is based on the fact that patients with NAFLD with advanced fibrosis are at greatest risk of developing complications of end-stage liver disease. Although it lacks sensitivity, ultrasonography is an accepted tool for steatosis screening. The controlled attenuation parameter or CAP seems a promising screening technique, but requires further validation. Cytokeratin-18 has been extensively validated, but it is an imperfect serum marker of NASH. Ultrasonography-based transient elastography can exclude advanced fibrosis and cirrhosis, but its main limitation is its reduced applicability in patients with NAFLD, which is not completely solved by use of the XL probe. Of the noninvasive serum markers, the NAFLD fibrosis score is the most validated and has appropriate accuracy in distinguishing patients with and without advanced fibrosis. Although noninvasive methods require further validation, they could be useful for selecting those patients with NAFLD who require a liver biopsy. This Review discusses the advantages and limitations of noninvasive methods for the management of adults with NAFLD, including diagnosis and quantification of steatosis, diagnosis of NASH and staging of hepatic fibrosis.

The CD47-binding peptide of thrombospondin-1 induces defenestration of liver sinusoidal endothelial cells

BACKGROUND & AIMS

A fenestrated phenotype is characteristic of liver sinusoidal endothelial cells (LSECs), but liver sinusoids become defenestrated during fibrosis and other liver diseases. Thrombospondin-1 (TSP1) is a matrix glycoprotein with pro-fibrotic effects, and the CD47-binding fragment of TSP1 also has anti-angiogenic effects in endothelial cells. We hypothesized that the CD47-binding fragment of TSP1 could induce defenestration in LSECs through the Rho-Rho kinase (ROCK)-myosin pathway.

METHODS

Freshly isolated rat LSECs were treated with TSP1 or CD47-binding peptides of TSP1. LSEC fenestration was assessed with scanning electron microscopy, and myosin phosphorylation was assessed with immuno-fluorescence.

RESULTS

Treating LSECs with TSP1 caused a dose-dependent loss of fenestrae, and this effect could not be blocked by SB-431542, the TGF-β1 receptor inhibitor. A CD47-binding fragment of TSP1, p4N1, was able to induce defenestration, and a CD47-blocking antibody, B6H12, was able to suppress p4N1-induced defenestration. The p4N1 fragment also caused contraction of fenestra size, correlated with an increase in myosin activation. Pretreatment with Y-237642 (a ROCK inhibitor) prevented p4N1-induced myosin activation and fenestrae decrease. Simvastatin has also been shown to antagonize Rho-ROCK signalling, and we found that simvastatin pretreatment protected LSECs from p4N1-induced myosin activation and defenestration.

CONCLUSIONS

We conclude that CD47 signals through the Rho-ROCK-myosin pathway to induce defenestration in LSECs. In addition, our results show that simvastatin and Y-237642 have a beneficial impact on fenestration in vitro, providing an additional explanation for the efficacy of these compounds for regression of liver fibrosis.

Non-alcoholic fatty liver disease: non-invasive investigation and risk stratification

Non-alcoholic fatty liver disease (NAFLD) encompasses a histological spectrum of liver disease, from simple steatosis through to cirrhosis. As the worldwide rates of obesity have increased, NAFLD has become the commonest cause of liver disease in many developed countries, affecting up to a third of the population. The majority of patients have simple steatosis that carries a relatively benign prognosis. However, a significant minority have non-alcoholic steatohepatitis, and have increased liver related and cardiovascular mortality. Identifying those at risk of progressive disease is crucial. Liver biopsy remains the gold standard investigation for assessing stage of disease but its invasive nature makes it impractical for widespread use as a prognostic tool. Non-invasive tools for diagnosis and disease staging are required, reserving liver biopsy for those patients where it offers clinically relevant additional information. This review discusses the non-invasive modalities available for assessing steatosis, steatohepatitis and fibrosis. We propose a pragmatic approach for the assessment of patients with NAFLD to identify those at high risk of progressive disease who require referral to specialist services.

Surface functionalization of styrenic block copolymer elastomeric biomaterials with hyaluronic acid via a "grafting to" strategy

As a biostable elastomer, the hydrophobicity of styrenic block copolymer (SBC) intensely limits its biomedical applications. In order to overcome such shortcoming, the SBC films were grafted with hyaluronic acid (HA) using a coupling agent. The surface chemistry of the modified films was examined by ATR-FTIR and XPS techniques, and the surface morphology was visually described by AFM. The biological performances of the HA-modified films were evaluated by a series of experiments, such as protein adsorption, platelet adhesion, and in vitro cytocompatibility. It was found that the HA-modified samples showed a low adhesiveness to fibroblast at the initial stage; however, it stimulated the growth of fibroblast. The L929 fibroblast growth presented a strong dependence on the molecular weight (MW) of HA. The samples modified with 17kDa HA exhibited the worst wettability and platelet adhesion, while providing the best results of supporting fibroblast proliferation.

Serum biomarkers in nonalcoholic steatohepatitis: value for assessing drug effects?

Nonalcoholic steatohepatitis (NASH) is a common chronic liver disease throughout the world. In the USA, approximately 3-5% of the population are affected, and the prevalence of this condition is increasing. NASH is associated with an increased risk of liver-related morbidity, such as cirrhosis and fibrosis, as well as cardiovascular disease, and in spite of several clinical studies investigating putative new drugs, no approved treatment is currently available. This is partly due to the nature of the disease. NASH is a complex, slowly progressing disease, and confirmatory clinical trials have long treatment durations and require invasive end points (a liver biopsy). Such invasive assessments are only accepted in confirmatory trials; clinical studies in the exploratory clinical development phase must rely on noninvasive biomarkers as the primary end point. Experimental and clinical research continues to achieve validation and qualification of biomarkers in NASH, which will hopefully assist the development of new treatments for NASH patients.

Non-invasive diagnosis of non-alcoholic fatty liver disease. A critical appraisal

Non-alcoholic fatty liver disease (NAFLD) affects one in every three subjects in the occidental world. The vast majority will not progress, but a relevant minority will develop liver cirrhosis and its complications. The classical gold standard for diagnosing and staging NAFLD and assessing fibrosis is liver biopsy (LB). However, it has important sample error issues and subjectivity in the interpretation, apart from a small but real risk of complications. The decision to perform an LB is even harder in a condition so prevalent such as NAFLD, in which the probability of finding severe liver injury is low. In an attempt to overcome LB and to subcategorize patients with NAFLD in different prognoses allowing better management decisions, several non-invasive methods have been studied in the last decade. The literature is vast and confusing. This review will summarize which methods have been tested and how they perform, which tests are adequate for clinical practice and how they can change the management of these patients.

Markers in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD), the most common liver disorder worldwide, encompasses a spectrum of abnormal liver histology ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Population studies show that NAFLD is strongly associated with insulin resistance, obesity, type 2 diabetes mellitus, and lipid abnormalities. In the context of hepatic steatosis, factors that promote cell injury, inflammation, and fibrosis include oxidative stress, early mitochondrial dysfunction, endoplasmic reticulum stress, iron accumulation, apoptosis, adipocytokines, and stellate cell activation. The exact NASH prevalence is unknown because of the absence of simple noninvasive diagnostic tests. Although liver biopsy is the "gold standard" for the diagnosis of NASH, other tests are needed to facilitate the diagnosis and greatly reduce the requirement for invasive liver biopsy. In addition, the development of new fibrosis markers in NASH is needed to facilitate the assessment of its progression and the effectiveness of new therapies. The aim of this chapter, which is overview of biomarkers in NASH, is to establish a systematic approach to laboratory findings of the disease.

Overview and developments in noninvasive diagnosis of nonalcoholic fatty liver disease

High prevalence of non-alcoholic fatty liver disease (NAFLD) and very diverse outcomes that are related to disease form and severity at presentation have made the search for noninvasive diagnostic tools in NAFLD one of the areas with most intense development in hepatology today. Various methods have been investigated in the recent years, including imaging methods like ultrasound and magnetic resonance imaging, different forms of liver stiffness measurement, various biomarkers of necroinflammatory processes (acute phase reactants, cytokines, markers of apoptosis), hyaluronic acid and other biomarkers of liver fibrosis. Multicomponent tests, scoring systems and diagnostic panels were also developed with the purposes of differentiating non-alcoholic steatohepatitis from simple steatosis or discriminating between various fibrosis stages. In all of the cases, performance of noninvasive methods was compared with liver biopsy, which is still considered to be a gold standard in diagnosis, but is by itself far from a perfect comparative measure. We present here the overview of the published data on various noninvasive diagnostic tools, some of which appear to be very promising, and we address as well some of still unresolved issues in this interesting field.

Can NASH be diagnosed, graded, and staged noninvasively?

Nonalcoholic bland steatosis and nonalcoholic steatohepatitis (NASH) are stages in the spectrum of nonalcoholic fatty liver disease (NAFLD). NASH may progress to end-stage liver disease. Liver biopsy distinguishes between patients with NASH and no NASH and can stage fibrosis. Markers of hepatocyte apoptosis hold promise as noninvasive tests for NASH diagnosis. Several scoring systems that combine routine clinical and laboratory variables and some proprietary panels can assist in predicting fibrosis severity. Noninvasive imaging modalities are reasonably accurate available tools to determine severity of fibrosis in NAFLD, but none of them yet can replace liver biopsy.

Predictive accuracy of serum hyaluronic acid as a non-invasive marker of fibrosis in a cohort of multi-transfused Egyptian children with β-thalassaemia major

BACKGROUND AND STUDY AIM

Liver disease remains a major cause of morbidity and mortality in patients with β-thalassaemia major (β-TM); therefore, its identification at an early stage is of great significance. Serum hyaluronic acid (HA) is considered as a non-invasive marker that appears early before pathological changes occur. We aim to determine the predictive accuracy of HA in detecting and staging hepatic fibrosis in β-TM patients.

PATIENTS AND METHODS

30 Egyptian children with β-TM, and 15 age and sex-matched controls were studied. All had abdominal ultrasonography (US), measurement of serum amino-transferases (ALT, AST); hepatitis C, B and human immunodeficiency viruses (HCV, HBV, HIV) sero-markers, serum ferritin and HA. Liver biopsy was done for patients and fibrosis was scaled using Metavir scoring system and liver iron concentration (LIC) was measured.

RESULTS

Twenty patients (67.7%) had sero-markers of HCV, none had HBV or HIV. Serum HA was significantly higher in patients (90.78±28.79 ng/ml) compared to controls (21.1±13.24 ng/ml) with p<0.05. No difference between HCV infected and non-infected patients was detected. Positive significant correlation was detected between serum HA and stages of fibrosis by histopathology and US. No correlation was found between serum HA and age, sex, weight, height, haemoglobin level, platelet count, AST, serum ferritin, necro-inflammatory grade, and LIC.

CONCLUSIONS

Serum HA is a valuable non-invasive marker that may contribute to the assessment of liver fibrosis in multi-transfused children and adolescents with β-TM, irrespective of concomitant HCV infection.

Non-invasive Diagnosis of Fibrosis in Non-alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed as well as in developing countries. Its prevalence continues to rise currently affecting approximately 20-30% of adults and 10% of children in the United States. Non-alcoholic fatty liver disease represents a wide spectrum of conditions ranging from fatty liver, which in general follows a benign non-progressive clinical course, to non-alcoholic steatohepatitis (NASH), a more serious form of NAFLD that may progress to cirrhosis and end-stage liver disease. Liver biopsy remains the gold standard for evaluating the degree of hepatic necroinflammation and fibrosis; however, several non-invasive investigations, such as serum biomarkers, have been developed to establish the diagnosis and also to evaluate treatment response. There has been a substantial development of non-invasive risk scores, biomarker panels, and radiological modalities to identify at risk patients with NAFLD without recourse to liver biopsy on a routine basis. Examples include combination of serum markers like NAFLD fibrosis score (NFS), BARD score, fibrometer, FIB4, and non-invasive tools like fibroscan which assess fibrosis in patients with NAFLD. Other markers of fibrosis that have been evaluated include high-sensitivity C-reactive protein, plasma pentraxin 3, interleukin-6, and cytokeratin-18. This review focuses on the methods currently available in daily clinical practice in hepatology and touches briefly on the potential future markers under investigation.

Prevalence and markers of advanced liver disease in type 2 diabetes

BACKGROUND

Type 2 diabetes is a risk factor for progression of non-alcoholic fatty liver disease (NAFLD) to fibrosis and cirrhosis. We examined the prevalence of advanced liver disease in people with type 2 diabetes and analysed the effectiveness of liver function tests (LFTs) as a screening tool.

METHODS

Participants (n = 939, aged 61-76 years) from the Edinburgh Type 2 Diabetes Study, a randomly selected population of people with type 2 diabetes, underwent abdominal ultrasonography. Hyaluronic acid (HA) and platelet count/spleen diameter ratio (PSR) were used as non-invasive markers of hepatic fibrosis and portal hypertension. Subjects were screened for secondary causes of liver disease that excluded them from a diagnosis of NAFLD. The efficacy of LFTs [alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT)] in screening for liver disease was determined.

RESULTS

Cirrhosis was identified by ultrasound in four participants (0.4%). Ten (1.1%) had evidence of portal hypertension (PSR < 909), and two (0.2%) had hepatocellular carcinoma. Fifty-three participants (5.7%) had evidence of hepatic fibrosis (HA > 100 ng/ml in the absence of joint disease); a further 169 had HA > 50 ng/ml. In participants with NAFLD-related fibrosis (HA > 100 ng/ml), 12.5% had an elevated ALT level and 17.5% had an elevated GGT level.

CONCLUSION

The prevalence of hepatic fibrosis and cirrhosis were lower than expected. The use of LFTs to screen for liver disease missed most cases of fibrosis predicted by raised HA levels.

Validation of the FIB4 index in a Japanese nonalcoholic fatty liver disease population

BACKGROUND

A reliable and inexpensive noninvasive marker of hepatic fibrosis is required in patients with nonalcoholic fatty liver disease (NAFLD). FIB4 index (based on age, aspartate aminotransferase [AST] and alanine aminotransferase [ALT] levels, and platelet counts) is expected to be useful for evaluating hepatic fibrosis. We validated the performance of FIB4 index in a Japanese cohort with NAFLD.

METHODS

The areas under the receiver operating characteristic curves (AUROC) for FIB4 and six other markers were compared, based on data from 576 biopsy-proven NAFLD patients. Advanced fibrosis was defined as stage 3-4 fibrosis. FIB4 index was assessed as: age (yr) × AST (IU/L)/(platelet count (10(9)/L) × √ALT (IU/L)) RESULTS: Advanced fibrosis was found in 64 (11%) patients. The AUROC for FIB4 index was superior to those for the other scoring systems for differentiating between advanced and mild fibrosis. Only 6 of 308 patients with a FIB4 index below the proposed low cut-off point (< 1.45) were under-staged, giving a high negative predictive value of 98%. Twenty-eight of 59 patients with a FIB4 index above the high cut-off point (> 3.25) were over-staged, giving a low positive predictive value of 53%. Using these cutoffs, 91% of the 395 patients with FIB-4 values outside 1.45-3.25 would be correctly classified. Implementation of the FIB4 index in the Japanese population would avoid 58% of liver biopsies.

CONCLUSION

The FIB4 index was superior to other tested noninvasive markers of fibrosis in Japanese patients with NAFLD, with a high negative predictive value for excluding advanced fibrosis. The small number of cases of advanced fibrosis in this cohort meant that this study had limited power for validating the high cut-off point.

YKL-40 and transient elastography, a powerful team to assess hepatic fibrosis

OBJECTIVE

Transient elastography (TE) is a non-invasive and accurate method for the diagnosis of severe hepatic fibrosis and cirrhosis (F = 3 and F = 4). However, the assessment of significant fibrosis (F = 2) by TE is impaired due to a high variation in the diagnostic accuracy. Within this study, we aim to compare the diagnostic value of TE and experimental biomarkers of liver fibrosis.

MATERIAL AND METHODS

A total of 55 patients with chronic liver disease of different etiologies were included in the study. Among them, patients with HCV infection represented the largest cohort (n = 25). Liver fibrosis was evaluated according to the Desmet/Scheuer score. All patients received TE. Serum concentrations of YKL-40, hyaluronic acid (HA), Laminin, C-terminal procollagen I peptide, MMP-9, TIMP-1, TIMP-2 and MMP-9/TIMP-1 complex were determined by ELISA.

RESULTS

In the total patient population, areas under the receiver operator characteristic curve (AUROC) for TE were 0.798 (F ≥ 2), 0.880 (F ≥ 3) and 1 (F = 4). Among the serum markers, highest diagnostic accuracies were calculated for YKL-40 for F ≥ 2 (0.792) and F ≥ 3 (0.914) and for YKL-40 and HA for F = 4 (both 0.936). In the subgroup of HCV patients, the following AUROCs for TE were calculated: 0.802 (F ≥ 2), 0.798 (F ≥ 3) and 0.998 (F = 4). YKL-40 exhibited the highest diagnostic accuracy of all biomarkers in the HCV population (0.880, 0.854 and 0.986, respectively).

CONCLUSIONS

YKL-40 is a powerful fibrosis marker with high diagnostic accuracy, in particular in HCV-associated liver disease. Its determination may confirm and improve the diagnostic accuracy of TE especially in early stages of liver fibrosis.

Diagnosis and evaluation of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of elevated liver function tests results, after the commonly investigated causes have been excluded, and frequently coexists with type 2 diabetes mellitus (T2DM) because the conditions have common risk factors. As both T2DM and NAFLD are related to adverse outcomes of the other, diagnosis and valuation of fatty liver is an important part of the management of diabetes. Although noninvasive methods, such as biomarkers, panel markers, and imaging, may support a diagnostic evaluation of NAFLD patients, accurate histopathological findings cannot be achieved without a liver biopsy. As it is important to know whether steatohepatitis and liver fibrosis are present for the management of NAFLD, liver biopsy remains the gold standard for NAFLD diagnosis and evaluation. Therefore, new investigations of the pathogenesis of NAFLD are necessary to develop useful biomarkers that could provide a reliable noninvasive alternative to liver biopsy.

Systematic review of performance of non-invasive biomarkers in the evaluation of non-alcoholic fatty liver disease

This systematic review evaluates the many studies carried out to discover and evaluate non-invasive markers of non-alcoholic fatty liver disease (NAFLD). Many different strategies and methods have been used in this task, from the discovery of new markers by global 'shotgun' studies to hypothesis-driven approaches, to the development of algorithm tests based on routinely available clinical and biochemical parameters. We examined the various different approaches, summarising the findings in an attempt to give an overview of the field of non-invasive markers in NAFLD, encompassing markers of steatosis, necro-inflammation and fibrosis. The body of literature surrounding this topic is complex and varied, encompassing not only different methodologies but also different patient characteristics, different disease definitions, as well as different end points. This reflects the heterogeneity of NAFLD, which, however, introduces considerably difficulty when trying to draw a conclusion between studies. We have divided this review into three main chapters based on the characteristics of the studies. The Genomics/Proteomics chapter reviews studies using a non-hypothesis-driven approach to biomarker discovery. Thereafter, we evaluate studies of association - studies that target-specific markers, comparing levels between disease and control groups. Finally, we examine the algorithm tests - mathematical systems developed on the basis of previously described markers and assessed, usually, by receiver operator curve analysis. While radiological examination and investigations offer important diagnostic information, such studies are not discussed in this review - the body of literature surrounding blood and anthropological markers is complex and varied, demanding close attention.

[Non-alcoholic fatty liver disease. How and who to screen]

Non-alcoholic fatty acid disease (NAFLD) can develop in the context of multiple processes but the main etiologic association is undoubtedly with insulin resistance syndrome. The present review aims to provide a systematic diagnostic approach that should include the following basic elements: a) a suspected diagnosis of NAFLD, including confirmation of abstinence from alcohol, exclusion of other potential causes of liver steatosis and diagnosis of potential associated diseases; b) diagnosis of insulin resistance; c) diagnosis of potential associated diseases; d) adequate evaluation of vascular risk; e) diagnosis of the type and localization of fat, and finally, f) evaluation of the severity of NAFLD, which can be performed through invasive and non-invasive techniques.

Systematic review: the diagnosis and staging of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent cause of liver disease in Western countries. The development of non-alcoholic steatohepatitis (NASH) and fibrosis identifies an at-risk group with increased risk of cardiovascular and liver-related deaths. The identification and management of this at-risk group remains a clinical challenge.

AIM

To perform a systematic review of the established and emerging strategies for the diagnosis and staging of NAFLD.

METHODS

Relevant research and review articles were identified by searching PubMed, MEDLINE and EMBASE.

RESULTS

There has been a substantial development of non-invasive risk scores, biomarker panels and radiological modalities to identify at-risk patients with NAFLD without recourse to liver biopsy on a routine basis. These modalities and algorithms have improved significantly in their diagnosis and staging of fibrosis and NASH in patients with NAFLD, and will likely impact on the number of patients undergoing liver biopsy.

CONCLUSIONS

Staging for NAFLD can now be performed by a combination of radiological and laboratory techniques, greatly reducing the requirement for invasive liver biopsy.

A brief review on molecular, genetic and imaging techniques for HCV fibrosis evaluation

Background

Chronic HCV is one of the major causes of morbidity and mortality in the present day world. The assessment of disease progression not only provides useful information for diagnosis and therapeutic supervision judgment but also for monitoring disease. Different invasive and non invasive methods are applied to diagnose the disease from initial to end stage (mild fibrosis to cirrhosis). Although, liver biopsy is still considered as gold standard to identify liver histological stages, an assessment of the disease development based on non-invasive clinical findings is also emerging and this may replace the need of biopsy in near future. This review gives brief insight on non-invasive methods currently available for predicting liver fibrosis in HCV with their current pros and cons to make easier for a clinician to choose better marker to assess liver fibrosis in HCV infected patients.

Methods

More than 200 studies regarding invasive and noninvasive markers available for HCV liver disease diagnosis were thoroughly reviewed. We examined year wise results of these markers based on their sensitivity, specificity, PPV, NPV and AUROCs.

Results

We found that in all non-invasive serum markers for HCV, FibroTest, Forn's Index, Fibrometer and HepaScore have high five-year predictive value but with low AUROCs (0.60~0.85) and are not comparable to liver biopsy (AUROC = 0.97). Even though from its beginning, Fibroscan is proved to be best with high AUROCs (> 0.90) in all studies, no single noninvasive marker is able to differentiate all fibrosis stages from end stage cirrhosis. Meanwhile, specific genetic markers may not only discriminate fibrotic and cirrhotic liver but also differentiate individual fibrosis stages.

Conclusions

There is a need of marker which accurately determines the stage based on simplest routine laboratory test. Genetic marker in combination of imaging technique may be the better non invasive diagnostic method in future.

A simple clinical scoring system using ferritin, fasting insulin, and type IV collagen 7S for predicting steatohepatitis in nonalcoholic fatty liver disease

BACKGROUND

Liver histology is the gold standard for the diagnosis of nonalcoholic steatohepatitis (NASH). Noninvasive, simple, reproducible, and reliable biomarkers are greatly needed to differentiate NASH from nonalcoholic fatty liver disease (NAFLD).

METHODS

To construct a scoring system for predicting NASH, 177 Japanese patients with biopsy-proven NAFLD were enrolled. To validate the scoring system, 442 biopsy-proven NAFLD patients from eight hepatology centers in Japan were also enrolled.

RESULTS

In the estimation group, 98 (55%) patients had NASH. Serum ferritin [≥200 ng/ml (female) or ≥300 ng/ml (male)], fasting insulin (≥10 μU/ml), and type IV collagen 7S (≥5.0 ng/ml) were selected as independent variables associated with NASH, by multilogistic regression analysis. These three variables were combined in a weighted sum [serum ferritin ≥200 ng/ml (female) or ≥300 ng/ml (male) = 1 point, fasting insulin ≥10 μU/ml = 1 point, and type IV collagen 7S ≥5.0 ng/ml = 2 points] to form an easily calculated composite score for predicting NASH, called the NAFIC score. The area under the receiver operating characteristic (AUROC) curve for predicting NASH was 0.851 in the estimation group and 0.782 in the validation group. The NAFIC AUROC was the greatest among several previously established scoring systems for detecting NASH, but also for predicting severe fibrosis.

CONCLUSIONS

NAFIC score can predict NASH in Japanese NAFLD patients with sufficient accuracy and simplicity to be considered for clinical use.

Nonalcoholic fatty liver in Asia: Firmly entrenched and rapidly gaining ground

Nonalcoholic fatty liver disease (NAFLD) is becoming an important chronic liver disorder in Asia. Prevalence figures show regional variations but at least 10% of the general population in Asia have fatty liver. Fatty liver can develop with relatively small changes in weight (2-3 kg), often with increasing central adiposity. The metabolic syndrome may precede or follow NAFLD. Overt diabetes is present in one-third of cases but when oral glucose tolerance tests are performed, a further third of individuals have impaired glucose tolerance or diabetes. Natural history data are still scarce but cases of advanced hepatic fibrosis and hepatocellular carcinoma are now regularly reported. Many cases of cryptogenic cirrhosis are also attributable to NAFLD. Histological progression has been demonstrated for patients with NASH as well as for those with hepatic steatosis alone. Genetic factors may in part contribute to the rise in NAFLD. Polymorphisms within apolipoprotein C3 (APOC3) gene have been linked to NAFLD in lean Indian men. Although a number of other polymorphisms involving genes controlling adipose distribution, insulin signalling, adipokine responses and hepatic fibrosis have been reported, these studies have been underpowered. Transient elastography could help in detecting and monitoring hepatic fibrosis but further refinements in technique are necessary for obese individuals. Of the biomarkers, hyaluronic acid and cytokeratin-18 fragment testing show promise as markers of hepatic fibrosis and NASH, respectively. Lifestyle alterations including dietary changes and increased physical activity remain the cornerstone of management. Attention should be paid to prevention through public education of campaigns addressing the increase in both adult and childhood obesity.

Hyaluronic acid predicts hepatic fibrosis in children with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adolescents, and it may progress to liver fibrosis and cirrhosis. Liver biopsy, which is the recognized gold standard for the diagnosis of hepatic fibrosis, is invasive. Thus, there has been increasing interest in the development of noninvasive markers. Hyaluronic acid (HA) has been shown to be a good marker of liver fibrosis in adults. In the current study, we evaluated the association of HA with liver fibrosis in 100 consecutive children with biopsy-proven NAFLD. In all, 65% of the children had liver fibrosis. Using proportional-odds ordinal logistic regression, we found that values of HA ≥ 1200 ng/mL made the absence of fibrosis (F0) unlikely (7%, 95% confidence interval [CI]: 1% to 14%), whereas values of HA ≥ 2100 ng/mL made F2, F3, or F4 fibrosis likely (89%, 95% CI: 75% to 100%). Our study shows that HA is a predictor of fibrosis in children with NAFLD followed at a tertiary care center. Additional studies are needed to test whether HA can be employed to predict liver fibrosis in pediatric populations with similar and lower prevalence of liver fibrosis.

Assessment of liver stiffness in subjects affected by familial combined hyperlipidaemia with hepatic steatosis

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) represents a spectrum of diseases ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) and is associated with familial combined hyperlipidaemia (FCHL). Currently, the invasive liver biopsy is considered as the gold standard for evaluating liver fibrosis (LF); however, liver stiffness measurement (LSM) by transient elastography (TE) trough FibroScan device may be employed to estimate LF noninvasively. The aim of this study was to evaluate the prevalence of NAFLD in FCHL subjects and to analyse LSM with TE to better identify those individuals with a potential risk of liver disease progression.

MATERIALS AND METHODS

Sixty subjects with FCHL (38 men, 22 women, mean age 46.4 +/- 10.9 years) were included in the study. We studied biochemical parameters including lipid profile, glucose, transaminase and insulin; blood pressure and waist circumference (WC) were measured; BMI and HOMA-index were calculated. Ultrasonography was performed to assess liver steatosis and carotid intima-media thickness (IMT). Liver fibrosis was measured by FibroScan.

RESULTS

Patients were classified according to have no (group 0: 19%), mild (group 1: 32%) or moderate-severe (group 2: 49%) steatosis. No difference was found between group 0 and 1 concerning all study parameters. WC (P < 0.05), BMI (P < 0.05), glucose (P < 0.05), insulin (P < 0.001), HOMA-index (P < 0.001) and LSM (6.03 +/- 1.9 Kpa vs. 4.2 +/- 0.5 Kpa, P < 0.001) were significantly higher in group 2 than groups 1 and 0. Furthermore, LSM correlated with insulin (P < 0.05), glucose (P < 0.05), HOMA-index (P < 0.001), transaminase (P < 0.01) and liver steatosis (P < 0.001). Regression analysis showed that LSM (P < 0.001) and NAFLD (P < 0.01) is associated with HOMA-index; NAFLD is also associated with WC (P < 0.05).

CONCLUSION

Our results suggest that in FCHL subjects, HOMA-index, an insulin resistance index, is strongly associated with liver steatosis and its progression. Furthermore, in these subjects, we propose the transient elastography to identify and follow up patients for the progression of hepatic disease.

Shear wave velocity is a useful marker for managing nonalcoholic steatohepatitis

AIM: To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis (NASH).

METHODS: In total 26 patients, 23 NASHs and 3 normal controls were enrolled in this study. NASH was staged based on Brunt criterion. At a region of interest (ROI), a shear wave was evoked by implementing an acoustic radiation force impulse (ARFI), and the propagation velocity was quantified.

RESULTS: Shear wave velocity (SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases, in which a reliable SWV value was not calculated at several ROIs. An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4, respectively, but was not significantly different from 1.79 ± 0.78 m/s in stage 2. When a cutoff value was set at 1.47 m/s, receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1 (P = 0.0092) with sensitivity, specificity and area under curve of 100%, 75% and 94.2%, respectively. In addition, the correlation between SWV and hyaluronic acid was significant (P < 0.0001), while a tendency toward negative correlation was observed with serum albumin (P = 0.053).

CONCLUSION: The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position, which has the potential to shed new light on NASH management.

Nonalcoholic fatty liver disease: a review and update

The spectrum of nonalcoholic fatty liver disease (NAFLD) ranges from asymptomatic steatosis to nonalcoholic steatohepatitis (NASH) and cirrhosis. Hepatic steatosis occurs when free fatty acids, released in the setting of insulin resistance and the metabolic syndrome, are taken up by the liver. Additional biochemical insults, including oxidative stress, upregulation of inflammatory mediators, and dysregulated apoptosis, can result in inflammation (producing NASH) and fibrosis. Noninvasive methods (e.g., abdominal ultrasonography) are safe ways to support a diagnosis of hepatic steatosis, but advanced liver histopathologic findings including NASH and fibrosis cannot be identified without pursuing liver biopsy. Recent advances in serologic and imaging methods aim to determine severity of inflammation and fibrosis noninvasively. Currently, therapeutic options for NAFLD are limited to medications that reduce risk factors, but the future holds promise for therapies that might slow the progression of this increasingly prevalent disorder.

Nonalcoholic steatohepatitis, animal models, and biomarkers: what is new?

Nonalcoholic fatty liver disease (NAFLD) is a clinicopathological term that encompasses a spectrum of abnormalities ranging from simple triglyceride accumulation in the hepatocytes (hepatic steatosis) to hepatic steatosis with inflammation (steatohepatitis, also known as nonalcoholic steatohepatitis or NASH). NASH can also progress to cirrhosis and hepatocellular carcinoma (HCC). Steatohepatitis has been estimated to affect around 5% of the total population and 20% of those who are overweight. The mechanisms leading to NASH and its progression to cirrhosis and HCC remain unclear, but it is a condition typically associated with obesity, insulin resistance, diabetes, and hypertriglyceridemia. This point corroborates the need for animal models and molecular markers that allow us to understand the mechanisms underlying this disease. Nowadays, there are numerous mice models to study abnormal liver function such as steatosis, NASH, and hepatocellular carcinoma. The study of the established animal models has provided many clues in the pathogenesis of steatosis and steatohepatitis, although these remain incompletely understood and no mice model completely fulfills the clinical features observed in humans. In addition, there is a lack of accurate sensitive diagnostic tests that do not involve invasive procedures. Current laboratory tests include some biochemical analysis, but their utility for diagnosing NASH is still poor. For that reason, a great effort is being made toward the identification and validation of novel biomarkers to assess NASH using high-throughput analysis based on genomics, proteomics, and metabolomics. The most recent discoveries and their validation will be discussed.

Serum proteomics and biomarker discovery across the spectrum of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), ranging from relatively benign simple steatosis to progressive nonalcoholic steatohepatitis (NASH) and fibrosis, is an increasingly common chronic liver disease. Liver biopsy is currently the only reliable tool for staging the subtypes of NAFLD; therefore, noninvasive serum biomarkers for evaluation of liver disease and fibrosis are urgently needed. We performed this study to describe changes in the serum proteome and identify biomarker candidates in serum samples from 69 patients with varying stages of NAFLD (simple steatosis, NASH, and NASH with advanced bridging [F3/F4] fibrosis) and 16 obese controls. Using a label-free mass spectrometry-based approach we identified over 1,700 serum proteins with a peptide identification (ID) confidence level of >75%, 605 of which changed significantly between any two patient groups (false discovery rate <5%). Importantly, expression levels of 55 and 15 proteins changed significantly between the simple steatosis and NASH F3/F4 group and the NASH and NASH F3/F4 group, respectively. Classification of proteins with significant changes showed involvement in immune system regulation and inflammation, coagulation, cellular and extracellular matrix structure and function, and roles as carrier proteins in the blood. Further, many of these proteins are synthesized exclusively by the liver and could potentially serve as diagnostic biomarkers for identifying and staging NAFLD.

CONCLUSION

This proteomic analysis reveals important information regarding the pathogenesis/progression of NAFLD and NASH and demonstrates key changes in serum protein expression levels between control subjects and patients with different stages of fatty liver. Future validation of these potential biomarkers is needed such that these proteins may be used in place of liver biopsy to facilitate diagnosis and treatment of patients with NAFLD.