Performance of ELF serum markers in predicting fibrosis stage in pediatric non-alcoholic fatty liver disease

A Precision Medicine Guided Approach to the Utilization of Biomarkers in MASLD

The new nomenclature of metabolic dysfunction-associated steatotic liver disease (MASLD) emphasizes a positive diagnosis based on cardiometabolic risk factors. This definition is not only less stigmatizing but also allows for subclassification and stratification, thereby addressing the heterogeneity of what was historically referred to as nonalcoholic fatty liver disease. The heterogeneity within this spectrum is influenced by several factors which include but are not limited to demographic/dietary factors, the amount of alcohol use and drinking patterns, metabolic status, gut microbiome, genetic predisposition together with epigenetic factors. The net effect of this dynamic and intricate system-level interaction is reflected in the phenotypic presentation of MASLD. Therefore, the application of precision medicine in this scenario aims at complex phenotyping with consequent individual risk prediction, development of individualized preventive strategies, and improvements in the clinical trial designs. In this review, we aim to highlight the importance of precision medicine approaches in MASLD, including the use of novel biomarkers of disease, and its subsequent utilization in future study designs.

Accuracy of a sequential algorithm based on FIB-4 and ELF to identify high-risk advanced liver fibrosis at the primary care level

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease, and liver fibrosis is the strongest predictor of morbimortality. We aimed to assess the performance of a sequential algorithm encompassing the Fibrosis 4 (FIB-4) and Enhanced Liver Fibrosis (ELF) scores for identifying patients at risk of advanced fibrosis. This cross-sectional study included one hospital-based cohort with biopsy-proven NAFLD (n = 140) and two primary care cohorts from different clinical settings: Type 2 Diabetes (T2D) follow-up (n = 141) and chronic liver disease (CLD) initial study (n = 138). Logistic regression analysis was performed to assess liver fibrosis diagnosis models based on FIB-4 and ELF biomarkers. The sequential algorithm retrieved the following accuracy parameters in predicting stages F3-4 in the biopsy-confirmed cohort: sensitivity (85%), specificity (73%), negative predictive value (79%) and positive predictive value (81%). In both T2D and CLD cohorts, a total of 28% of patients were classified as stages F3-4. Furthermore, of all F3-4 classified patients in the T2D cohort, 80% had a diagnosis of liver disease and 44% were referred to secondary care. Likewise, of all F3-4 classified patients in the CLD cohort, 71% had a diagnosis of liver disease and 44% were referred to secondary care. These results suggest the potential utility of this algorithm as a liver fibrosis stratifying tool in primary care, where updating referral protocols to detect high-risk F3-4 is needed. FIB-4 and ELF sequential measurement is an efficient strategy to prioritize patients with high risk of F3-4 in populations with metabolic risk factors.

UK guideline on the transition and management of childhood liver diseases in adulthood

INTRODUCTION

Improved outcomes of liver disease in childhood and young adulthood have resulted in an increasing number of young adults (YA) entering adult liver services. The adult hepatologist therefore requires a working knowledge in diseases that arise almost exclusively in children and their complications in adulthood.

AIMS

To provide adult hepatologists with succinct guidelines on aspects of transitional care in YA relevant to key disease aetiologies encountered in clinical practice.

METHODS

A systematic literature search was undertaken using the Pubmed, Medline, Web of Knowledge and Cochrane database from 1980 to 2023. MeSH search terms relating to liver diseases ('cholestatic liver diseases', 'biliary atresia', 'metabolic', 'paediatric liver diseases', 'autoimmune liver diseases'), transition to adult care ('transition services', 'young adult services') and adolescent care were used. The quality of evidence and the grading of recommendations were appraised using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

These guidelines deal with the transition of YA and address key aetiologies for the adult hepatologist under the following headings: (1) Models and provision of care; (2) screening and management of mental health disorders; (3) aetiologies; (4) timing and role of liver transplantation; and (5) sexual health and fertility.

CONCLUSIONS

These are the first nationally developed guidelines on the transition and management of childhood liver diseases in adulthood. They provide a framework upon which to base clinical care, which we envisage will lead to improved outcomes for YA with chronic liver disease.

Derivation and validation of Transform equations to convert historical Enhanced liver fibrosis (ELF) scores to modern equivalents

BACKGROUND AND AIMS

The Siemens Healthineers ELF™ Test was designed in 2004 with 2 algorithms to allow choice in histological alignment. Consequently, historical and modern algorithms are not fully harmonized, complicating comparisons involving early datasets. We derived transform equations to equate all ELF score versions, allowing historical data to be used in systematic reviews and meta-analyses.

METHODS

Historical ELF equations were graphed pairwise versus their modern equivalent to assess correlation and derive four transforms. Transforms were validated using multiple datasets and evaluated for median absolute bias, number of samples reflecting clinically significant bias, number of discordant samples, bias at established cutoffs, and regression slope and y-intercept.

RESULTS

Three transforms were validated equating Scheuer-aligned and/or age-included historical ELF equations (Immuno 1) to later equations aligned to Ishak and omitting age. A fourth transform corrected ADVIA Centaur® / Atellica® IM ELF scores miscalculated using the Scheuer Immuno 1 equation. Transformed data were well within allowable ELF bias limits.

CONCLUSIONS

All transforms enabled accurate comparison of ELF scores generated by all historical algorithms to the current ADVIA Centaur / Atellica IM Analyzer ELF score. The transforms presented in this report should be used in systematic reviews and meta-analyses to facilitate comparisons to historical data.

Updates in Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) in Children

The obesity epidemic is one of the major health concerns of the 21st century. Nonalcoholic fatty liver disease (NAFLD) is linked with the increased adiposity associated with obesity. NAFLD has become the most frequent cause of chronic liver disease in adults and children worldwide. Metabolic dysfunction-associated fatty liver disease (MAFLD) also known in children as pediatric fatty liver disease (PeFLD) type 2 has begun to supersede NAFLD as the preferred nomenclature in the pediatric population. Evidence suggests the etiology of MAFLD is multifactorial, related to the complex interplay of hormonal, nutritional, genetic, and environmental factors. Current limitations in accurate diagnostic biomarkers have rendered it a diagnosis of exclusion and it is important to exclude alternative or coexisting causes of PeFLD. Lifestyle changes and modifications remains the primary treatment modality in MAFLD in children. Weight loss of 7%-10% is described as reversing MAFLD in most patients. The Mediterranean diet also shows promise in reversing MAFLD. Pharmacological intervention is debatable in children, and though pediatric trials have not shown promise, other agents undergoing adult clinical trials show promise. This review outlines the latest evidence in pediatric MAFLD and its management.

Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes: Screening, Diagnosis, and Treatment

Nonalcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction-associated steatotic liver disease (MASLD) affects ~70% of patients with type 2 diabetes (T2D), with ~20% showing signs of advanced liver fibrosis. Patients with T2D are at an increased risk of developing cirrhosis, liver failure, and hepatocellular carcinoma and their liver-related mortality is doubled compared with non-diabetic individuals. Nonetheless, the condition is frequently overlooked and disease awareness is limited both among patients and among physicians. Given recent epidemiological evidence, clinical practice guidelines recommend screening for NAFLD/MASLD and advanced liver fibrosis in patients with T2D. While many drugs are currently being tested for the treatment of NAFLD/MASLD, none of them have yet received formal approval from regulatory agencies. However, several classes of antidiabetic drugs (namely pioglitazone, sodium-glucose transporter 2 inhibitors, glucagon-like peptide 1 receptor agonists, and multi-agonists) have shown favorable effects in terms of liver enzymes, liver fat content and, in some occasions, on histologic features such as inflammation and fibrosis. Therefore, diabetologists have the opportunity to actively treat NAFLD/MASLD, with a concrete possibility of changing the natural history of the disease. In the present narrative review, we summarize evidence and clinical recommendations for NAFLD/MAFLD screening in the setting of T2D, as well as on the effect of currently available glucose-lowering drugs on hepatic endpoints.

Steatotic Liver Disease: Metabolic Dysfunction, Alcohol, or Both?

Non-alcoholic fatty liver disease (NAFLD) and alcohol-related liver disease (ALD), both of them accounting for fatty liver disease (FLD), are among the most common chronic liver diseases globally, contributing to substantial public health burden. Both NAFLD and ALD share a similar picture of clinical presentation yet may have differences in prognosis and treatment, which renders early and accurate diagnosis difficult but necessary. While NAFLD is the fastest increasing chronic liver disease, the prevalence of ALD has seemingly remained stable in recent years. Lately, the term steatotic liver disease (SLD) has been introduced, replacing FLD to reduce stigma. SLD represents an overarching term to primarily comprise metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), as well as alcohol-related liver disease (ALD), and MetALD, defined as a continuum across which the contribution of MASLD and ALD varies. The present review discusses current knowledge on common denominators of NAFLD/MASLD and ALD in order to highlight clinical and research needs to improve our understanding of SLD.

Noninvasive biomarkers in pediatric nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease worldwide among children and adolescents. It encompasses a spectrum of disease, from its mildest form of isolated steatosis, to nonalcoholic steatohepatitis (NASH) to liver fibrosis and cirrhosis, or end-stage liver disease. The early diagnosis of pediatric NAFLD is crucial in preventing disease progression and in improving outcomes. Currently, liver biopsy is the gold standard for diagnosing NAFLD. However, given its invasive nature, there has been significant interest in developing noninvasive methods that can be used as accurate alternatives. Here, we review noninvasive biomarkers in pediatric NAFLD, focusing primarily on the diagnostic accuracy of various biomarkers as measured by their area under the receiver operating characteristic, sensitivity, and specificity. We examine two major approaches to noninvasive biomarkers in children with NAFLD. First, the biological approach that quantifies serological biomarkers. This includes the study of individual circulating molecules as biomarkers as well as the use of composite algorithms derived from combinations of biomarkers. The second is a more physical approach that examines data measured through imaging techniques as noninvasive biomarkers for pediatric NAFLD. Each of these approaches was applied to children with NAFLD, NASH, and NAFLD with fibrosis. Finally, we suggest possible areas for future research based on current gaps in knowledge.

Meta-analysis: Enhanced liver fibrosis test to identify hepatic fibrosis in chronic liver diseases

BACKGROUND & AIMS

Patients with liver disease can be stratified for risk of liver-related ill health by degree of hepatic fibrosis. The Enhanced liver fibrosis (ELF) test was developed to quantify hepatic fibrosis non-invasively and is widely used. The objective of this review was to identify and synthesise the evidence on the diagnostic accuracy of the ELF test for staging of hepatic fibrosis.

APPROACH & RESULTS

Searches of PubMed and EMBASE were conducted between October 2020 and November 2021 to identify studies reporting the diagnostic accuracy of the ELF test compared to histology in liver disease patients. QUADAS-2 was used to assess risk of bias in each study. Meta-analysis using the multiple thresholds model described by Steinhauser S, Schumacher M, Rücker G. Modelling multiple thresholds in meta-analysis of diagnostic test accuracy studies. BMC Med. Res. Methodol. 2016;16. 10.1186/s12874-016-0196-1 allowed synthesis of 2 × 2 data at different cut-offs. Sixty-three studies were included in this review. These studies included 19,285 patients with or at risk of liver disease from viral hepatitis, Non-Alcoholic Fatty Liver Disease, Alcohol-related Liver Disease and other mixed chronic liver diseases. The prevalence of significant fibrosis, advanced fibrosis and cirrhosis was 47.5%, 39.2% and 4.4%, respectively. Cut-offs with maximal Youden index were generated with AUROC = 0.811 (95% CI: 0.736-0.870), 0.812 (95% CI: 0.758-0.856) and 0.810 (95% CI: 0.694-0.888) to detect significant fibrosis, advanced fibrosis or cirrhosis, respectively. Diagnostic accuracy of the ELF test varied between different liver diseases and cut-offs to detect each stage with 95% sensitivity or specificity were also generated.

CONCLUSIONS

Meta-analysis revealed considerable variability in the ability of ELF to stage fibrosis across disease aetiologies. Research has mostly focused on viral hepatitis and NAFLD. There is currently a lack of data on the value of the ELF test in Alcohol-related liver disease and patients in primary care settings.

The Link between NAFLD and Metabolic Syndrome

Metabolic syndrome (MetS) is characterized by an association of cardiovascular and diabetes mellitus type 2 risk factors. Although the definition of MetS slightly differs depending on the society that described it, its central diagnostic criteria include impaired fasting glucose, low HDL-cholesterol, elevated triglycerides levels and high blood pressure. Insulin resistance (IR) is believed to be the main cause of MetS and is connected to the level of visceral or intra-abdominal adipose tissue, which could be assessed either by calculating body mass index or by measuring waist circumference. Most recent studies revealed that IR may also be present in non-obese patients, and considered visceral adiposity to be the main effector of MetS' pathology. Visceral adiposity is strongly linked with hepatic fatty infiltration also known as non-alcoholic fatty liver disease (NAFLD), therefore, the level of fatty acids in the hepatic parenchyma is indirectly linked with MetS, being both a cause and a consequence of this syndrome. Taking into consideration the present pandemic of obesity and its tendency to drift towards a progressively earlier onset due to the Western lifestyle, it leads to an increased NAFLD incidence. Novel therapeutic resources are lifestyle intervention with physical activity, Mediterranean diet, or therapeutic surgical respective metabolic and bariatric surgery or drugs such as SGLT-2i, GLP-1 Ra or vitamin E. NAFLD early diagnosis is important due to its easily available diagnostic tools such as non-invasive tools: clinical and laboratory variables (serum biomarkers): AST to platelet ratio index, fibrosis-4, NAFLD Fibrosis Score, BARD Score, fibro test, enhanced liver fibrosis; imaging-based biomarkers: Controlled attenuation parameter, magnetic resonance imaging proton-density fat fraction, transient elastography (TE) or vibration controlled TE, acoustic radiation force impulse imaging, shear wave elastography, magnetic resonance elastography; and the possibility to prevent its complications, respectively, fibrosis, hepato-cellular carcinoma or liver cirrhosis which can develop into end-stage liver disease.

Surveillance of the progression and assessment of treatment endpoints for nonalcoholic steatohepatitis

Nonalcoholic steatohepatitis (NASH) is an aggressive form of nonalcoholic fatty liver disease (NAFLD) characterized by steatosis-associated inflammation and liver injury. Without effective treatment or management, NASH can have life-threatening outcomes. Evaluation and identification of NASH patients at risk for adverse outcomes are therefore important. Key issues in screening NASH patients are the assessment of advanced fibrosis, differentiation of NASH from simple steatosis, and monitoring of dynamic changes during follow-up and treatment. Currently, NASH staging and evaluation of the effectiveness for drugs still rely on pathological diagnosis, despite sample error issues and the subjectivity associated with liver biopsy. Optimizing the pathological assessment of liver biopsy samples and developing noninvasive surrogate methods for accessible, accurate, and safe evaluation are therefore critical. Although noninvasive methods including elastography, serum soluble biomarkers, and combined models have been implemented in the last decade, noninvasive diagnostic measurements are not widely applied in clinical practice. More work remains to be done in establishing cost-effective strategies both for screening for at-risk NASH patients and identifying changes in disease severity. In this review, we summarize the current state of noninvasive methods for detecting steatosis, steatohepatitis, and fibrosis in patients with NASH, and discuss noninvasive assessments for screening at-risk patients with a focus on the characteristics that should be monitored at follow-up.

Screening strategy for non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, affecting approximately 25% of the general population worldwide, and is forecasted to increase global health burden in the 21st century. With the advancement of non-invasive tests for assessing and monitoring of steatosis and fibrosis, NAFLD screening is now feasible, and is increasingly highlighted in international guidelines related to hepatology, endocrinology, and pediatrics. Identifying high-risk populations (e.g., diabetes mellitus, obesity, metabolic syndrome) based on risk factors and metabolic characteristics for non-invasive screening is crucial and may aid in designing screening strategies to be more precise and effective. Many screening modalities are currently available, from serum-based methods to ultrasonography, transient elastography, and magnetic resonance imaging, although the diagnostic performance, cost, and accessibility of different methods may impact the actual implementation. A two-step assessment with serum-based fibrosis-4 index followed by imaging test vibration-controlled transient elastography can be an option to stratify the risk of liverrelated complications in NAFLD. There is a need for fibrosis surveillance, as well as investigating the cost-effectiveness of different screening algorithms and engaging primary care for first-stage triage screening.

Fatty liver disease in children (MAFLD/PeFLD Type 2): unique classification considerations and challenges

In children, fatty liver disease is a group of disorders that often overlaps with inherited metabolic disorders (IMDs), which requires prompt diagnosis and specific management. Metabolic dysfunction-associated fatty liver disease (MAFLD) or, formerly, non-alcoholic fatty liver disease (NAFLD) is the hepatic component of a multisystemic disease that requires a positive criteria in metabolic dysfunction for diagnosis. However, in children, the diagnosis of MAFLD is one of the exclusions of an IMD [paediatric fatty liver disease (PeFLD) type 1] including the possibility that an IMD can be identified in the future following investigations that may be negative at the time. Therefore, while children with fatty liver with metabolic dysfunction could be classified as MAFLD (PeFLD type 2) and managed that way, those who do not fulfil the criteria for metabolic dysfunction should be considered separately bearing in mind the possibility of identifying a yet undiagnosed IMD (PeFLD type 3). This concept is ever more important in a world where MAFLD is the most common cause of liver disease in children and adolescents in whom about 7% are affected. The disease is only partially understood, and awareness is still lacking outside hepatology and gastroenterology. Despite its increasing pervasiveness, the management is far from a one-size-fits-all. Increasing complexities around the genetic, epigenetic, non-invasive modalities of assessment, psychosocial impacts, therapeutics, and natural history of the disease have meant that an individualised approach is required. This is where the challenge lies so that children with fatty liver are considered on their own merits. The purpose of this review is to give a clinical perspective of fatty liver disease in children with relevance to metabolic dysfunction.

Non-invasive methods to evaluate liver fibrosis in patients with non-alcoholic fatty liver disease

Non-alcoholic Fatty Liver Disease (NAFLD) is a chronic liver disease that is strongly related to insulin resistance and metabolic syndrome, and it has become the most common liver disorder in developed countries. NAFLD embraces the full pathological process of three conditions: steatosis, non-alcoholic steatohepatitis, and finally, cirrhosis. As NAFLD progresses, symptoms will become increasingly severe as fibrosis develops. Therefore, evaluating the fibrosis stage is crucial for patients with NAFLD. A liver biopsy is currently considered the gold standard for staging fibrosis. However, due to the limitations of liver biopsy, non-invasive alternatives were extensively studied and validated in patients with NAFLD. The advantages of non-invasive methods include their high safety and convenience compared with other invasive approaches. This review introduces the non-invasive methods, summarizes their benefits and limitations, and assesses their diagnostic performance for NAFLD-induced fibrosis.

Ameliorative Effect of Pomegranate Peel Extract (PPE) on Hepatotoxicity Prompted by Iron Oxide Nanoparticles (Fe2O3-NPs) in Mice

An evaluation of the ameliorative effect of pomegranate peel extract (PPE) in counteracting the toxicity of iron oxide nanoparticles (Fe₂O₃-NPs) that cause hepatic tissue damage is focused on herein. Forty male albino mice were haphazardly grouped into four groups as follows: the first control group was orally gavage daily with physiological saline; the second group received 100 mg/kg of PPE by the oral route day after day; the third group received 30 mg/kg Fe₂O₃-NPs orally; and the fourth group received both PPE and Fe₂O₃-NPs by the oral route, the same as the second and third sets. Later, after the completion of the experiment, we collected the liver, blood, and bone marrow of bone specimens that were obtained for further laboratory tests. For instance, exposure to Fe₂O₃-NPs significantly altered serum antioxidant biomarkers by decreasing the levels of total antioxidant capacity (TAC), catalase (CAT), and glutathione s-transferase (GST). Additionally, it caused changes in the morphology of hepatocytes, hepatic sinusoids, and inflammatory Kupffer cells. Furthermore, they significantly elevated the number of chromosomal aberrations including gaps, breaks, deletions, fragments, polyploidies, and ring chromosomes. Moreover, they caused a significant overexpression of TIMP-1, TNF-α, and BAX mRNA levels. Finally, the use of PPE alleviates the toxicity of Fe₂O₃-NPs that were induced in the hepatic tissues of mice. It is concluded that PPE extract has mitigative roles against the damage induced by Fe₂O₃-NPs, as it serves as an antioxidant and hepatoprotective agent. The use of PPE as a modulator of Fe₂O₃-NPs' hepatotoxicity could be considered as a pioneering method in the use of phytochemicals against the toxicity of nanoparticles.

Evaluation of nonalcoholic fatty liver disease (NAFLD) in severe obesity using noninvasive tests and imaging techniques

The prevalence of nonalcoholic fatty liver disease (NAFLD) and the more severe and inflammatory type, nonalcoholic steatohepatitis (NASH), is increasing rapidly. Especially in high-risk patients, that is those with obesity, metabolic syndrome, and type 2 diabetes mellitus, the prevalence of NAFLD can be as high as 80% while NASH may be present in 20% of these subjects. With the worldwide increase of obesity, it is most likely that these numbers will rise. Since advanced stages of NAFLD and NASH are strongly associated with morbidity and mortality-in particular, cardiovascular disease, liver cirrhosis, and hepatocellular carcinoma-it is of great importance to identify subjects at risk. A great variety of noninvasive tests has been published to diagnose NAFLD and NASH, especially using blood- and imaging-based tests. Liver biopsy remains the gold standard for NAFLD/NASH. This review aims to summarize the different mechanisms leading to NASH and liver fibrosis, the different noninvasive liver tests to diagnose and evaluate patients with severe obesity.

Mitochondrial Dysfunction Plays Central Role in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a global pandemic that affects one-quarter of the world’s population. NAFLD includes a spectrum of progressive liver disease from steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis and can be complicated by hepatocellular carcinoma. It is strongly associated with metabolic syndromes, obesity, and type 2 diabetes, and it has been shown that metabolic dysregulation is central to its pathogenesis. Recently, it has been suggested that metabolic- (dysfunction) associated fatty liver disease (MAFLD) is a more appropriate term to describe the disease than NAFLD, which puts increased emphasis on the important role of metabolic dysfunction in its pathogenesis. There is strong evidence that mitochondrial dysfunction plays a significant role in the development and progression of NAFLD. Impaired mitochondrial fatty acid oxidation and, more recently, a reduction in mitochondrial quality, have been suggested to play a major role in NAFLD development and progression. In this review, we provide an overview of our current understanding of NAFLD and highlight how mitochondrial dysfunction contributes to its pathogenesis in both animal models and human subjects. Further we discuss evidence that the modification of mitochondrial function modulates NAFLD and that targeting mitochondria is a promising new avenue for drug development to treat NAFLD/NASH.

Antiplatelet drugs and liver fibrosis

Liver fibrosis results from an imbalance between extracellular matrix formation and degradation. The background of liver fibrosis is chronic inflammation and subsequent microcirculation disturbance including microthrombosis. Platelets actively participate in liver fibrosis not only as a part of the clotting system but also by releasing granules containing important mediators. In fact, platelets may play a dual role in the pathophysiology of liver fibrosis as they are able to stimulate regeneration as well as aggravate the destruction of the liver. Recent studies revealed that antiplatelet therapy correlates with inhibition of liver fibrosis. However, liver impairment is associated with extensive coagulation disorders thus the safety of antiplatelet therapy is an area for detailed exploration. In this review, the role of platelets in liver fibrosis and accompanying hemostatic disorders are discussed. Additionally, results of animal and human studies on antiplatelet drugs in liver disorders and their potential therapeutic utility are presented.

Advances in fibrosis biomarkers in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) affects a quarter of the adult world population and the degree of liver fibrosis represents the best predictor of the development of liver-related outcomes. Easily applicable and well performing non-invasive fibrosis tests can overcome the limitations of liver biopsy and are of paramount importance to identify at-risk subjects in clinical practice. While tests with optimal performance and ease of use do not exist at this stage, available markers can be divided in three broad groups: simple serum tests, complex serum tests and elastographic methods. Simple scores (such as Fibrosis-4 and NAFLD Fibrosis Score) are based on readily available biochemical data and clinical features, while complex/proprietary tests (such as Fibrotest, Enhanced Liver Fibrosis and Hepascore) directly measure markers of fibrogenesis and fibrolysis, but have higher costs. Elastography techniques estimate the degree of fibrosis from liver stiffness and are based on either ultrasound or magnetic resonance (MR) imaging. MR elastography has better performance compared with sonographic techniques and is not affected by obesity and inflammation, but is highly costly and less available. In general, non-invasive tests are able to exclude the presence of fibrosis, but their positive predictive value is low to moderate and they lead to a high number of indeterminate results. In this context, a combination of different tests might increase accuracy while reducing gray-zone results. Their ability to predict future events and response to treatment is suboptimal and needs to be studied further. Finally, recent studies have tried different approaches, spanning from "omics" to the microbiome and micro-RNAs, with some promising results.

Can the Enhanced Liver Fibrosis Score Be Used to Diagnose Children With Liver Fibrosis?

OBJECTIVES

The noninvasive Enhanced Liver Fibrosis (ELF) score is used in adults with liver fibrosis as a diagnostic aid. The ELF score combines 3 serum markers of extracellular matrix remodeling and fibrogenesis: hyaluronic acid (HA), the N-terminal pro-peptide of collagen type III (PIIINP), and tissue inhibitor of metalloproteinase-1 (TIMP-1). We aimed to evaluate the clinical use of the ELF score in children.

METHODS AND RESULTS

A reference interval for the ELF score was established using 343 liver-healthy children ages 6 to 17 years. The median ELF score of 8.9 in healthy children was significantly increased compared with healthy adults. ELF scores increased significantly in both female and male healthy controls with peak levels at puberty, driven by elevated levels of HA and PIIINP likely explained by increased growth. If adult normal values were applied to the group of liver-healthy children, only 6.4% were in the normal range. Prospectively, we analysed ELF scores in patients with possible or confirmed liver fibrosis because of autosomal recessive polycystic kidney disease (ARPKD). All ELF scores in children with ARPKD were within the reference intervals generated from the group of healthy children.

CONCLUSIONS

The usual diagnostic cut-off ranges for the ELF score in adults are not applicable; instead age and gender-appropriate cut-off values should be used in children. The clinical value of ELF scores in children is questionable as children during pubertal growth showed elevated ELF scores and patients with ARPKD and liver fibrosis showed normal levels.

The Neglected Role of Bile Duct Epithelial Cells in NASH

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease worldwide, and affects 25% of the population in Western countries. NAFLD is the hepatic manifestation of the metabolic syndrome, linked to insulin resistance, which is the common pathogenetic mechanism. In approximately 40% of NAFLD patients, steatosis is associated with necro-inflammation and fibrosis, resulting in nonalcoholic steatohepatitis (NASH), a severe condition that may progress to cirrhosis and liver cancer. Although the hepatocyte represents the main target of the disease, involvement of the bile ducts occurs in a subset of patients with NASH, and is characterized by ductular reaction and activation of the progenitor cell compartment, which incites portal fibrosis and disease progression. We aim to dissect the multiple biological effects that adipokines and metabolic alterations exert on cholangiocytes to derive novel information on the mechanisms driven by insulin resistance, which promote fibro-inflammation and carcinogenesis in NASH.

Higher Levels of Plasma Hyaluronic Acid and N-terminal Propeptide of Type III Procollagen Are Associated With Lower Kidney Function in Children With Non-alcoholic Fatty Liver Disease

OBJECTIVE

Hyaluronic acid (HA) and N-terminal propeptide of type III procollagen (PIIINP) are two non-invasive biomarkers of liver fibrosis in non-alcoholic fatty liver disease (NAFLD). We examined the relationships of plasma levels of HA and PIIINP with kidney function in children with NAFLD.

METHODS

Plasma HA and PIIINP levels were measured using two commercially available enzyme-linked immunosorbent assay kits in a cohort of 106 Caucasian overweight or obese children with biopsy-proven NAFLD. Glomerular filtration rate (eGFR) was estimated using the Bedside Schwartz equation. Genotyping for the patatin-like phospholipase domain-containing protein-3 (PNPLA3) rs738409 variant was performed using an allelic discrimination assay.

RESULTS

Children with fibrosis F2 had significantly higher plasma PIIINP and HA levels than those with F0 or F1 fibrosis. Liver fibrosis was positively associated with plasma HA and PIIINP, as well as with the presence of the risk allele G of PNPLA3 rs738409 variant, and negatively with eGFR. Moreover, eGFR showed significant inverse associations with HA and PIIINP levels, as well as the presence of G of PNPLA3 rs738409, and liver fibrosis stage. Notably, our multivariable regression models showed that higher plasma PIIINP (standardized beta coefficient: -0.206, P = 0.011) and HA levels (standardized beta coefficient: -0.531, P < 0.0001) were associated with lower eGFR values, even after adjustment for age, sex, systolic blood pressure, PNPLA3 rs738409 genotype, and any stage of liver fibrosis.

CONCLUSIONS

Higher levels of HA and PIIINP were associated with lower eGFR values in Caucasian children with biopsy-proven NAFLD, independently of PNPLA3 rs738409 genotype and other potential confounding factors.

Non-invasive assessment of fibrosis and steatosis in pediatric non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Non-Alcoholic Fatty Liver Disease (NAFLD) has become one of the most common causes of chronic liver disease in the pediatric population. Recent advances have been made in developing non-invasive measures for NAFLD assessment. This review presents an analysis of these latest developments and also proposes an algorithm for screening pediatric patients at risk for NAFLD.

METHODS

A systematic literature search on PUBMED and EMBASE was conducted. Guidelines for clinical care of pediatric NAFLD were also reviewed.

RESULTS

In imaging tests, transient elastography (TE) combined with controlled attenuation parameter (CAP) is a promising, relatively low-cost method offering an intermediate level of accuracy on accessing patient's fibrosis and steatosis in a singular package. Liver biopsy remains the gold standard for diagnosis and/or evaluation of NAFLD, but with our proposed algorithm on utilizing non-invasive testing, the number of liver biopsies required could decrease. The current evidence supports the implementation of TE and CAP in an evaluation algorithm for pediatric NAFLD.

CONCLUSIONS

Current data support the use of TE and CAP as a first-line tool in the diagnosis and evaluation of adolescent NAFLD, to better stratify high-risk patients and cut down on the number of liver biopsies needed.

Metabolic Fatty Liver Disease in Children: A Growing Public Health Problem

Metabolic-associated fatty liver disease (MAFLD), previously called nonalcoholic fatty liver diseases (NAFLD), is one of the most important causes of chronic liver disease worldwide and will likely become the leading cause of end-stage liver disease in the decades ahead. MAFLD covers a continuum of liver diseases from fatty liver to nonalcoholic steatohepatitis (NASH), liver fibrosis/cirrhosis and hepatocellular cancer. Importantly, the growing incidence of overweight and obesity in childhood, 4% in 1975 to 18% in 2016, with persisting obesity complications into adulthood, is likely to be harmful by increasing the incidence of severe MAFLD at an earlier age. Currently, MAFLD is the leading form of chronic liver disease in children and adolescents, with a global prevalence of 3 to 10%, pointing out that early diagnosis is therefore crucial. In this review, we highlight the current knowledge concerning the epidemiology, risk factors and potential pathogenic mechanisms, as well as diagnostic and therapeutic approaches, of pediatric MAFLD.

Relationship of Enhanced Liver Fibrosis Score with Pediatric Nonalcoholic Fatty Liver Disease Histology and Response to Vitamin E or Metformin

OBJECTIVES

To study the diagnostic performance of the enhanced liver fibrosis score (ELF) for detecting different stages of fibrosis and its usefulness in detecting histologic response to vitamin E or metformin in children with nonalcoholic fatty liver disease who participated in the Vitamin E or Metformin for the Treatment Of NAFLD In Children (TONIC) trial.

STUDY DESIGN

ELF was measured at baseline and weeks 24, 48, and 96 on sera from 166 TONIC participants. Associations between ELF with baseline and end of trial (EOT) fibrosis stages and other histologic features were assessed using χ² tests and logistic regression models.

RESULTS

ELF was significantly associated with severity of fibrosis at baseline and EOT. ELF areas under the curve for discriminating patients with clinically significant and advanced fibrosis were 0.70 (95% CI, 0.60-0.80) and 0.79 (95% CI, 0.69-0.89), respectively. A 1-unit decrease in ELF at EOT was associated with overall histologic improvement (OR, 1.86; 95% CI, 1.11-3.14; P = .02), resolution of steatohepatitis (OR, 1.88; 95% CI, 1.09-3.25; P = .02), improvement in steatosis grade (OR, 1.76; 95% CI, 1.06-2.82; P = .03), and hepatocellular ballooning (OR, 1.79; 95% CI, 1.06-3.00; P = .03), but not with improvement in fibrosis stage (OR, 1.26; 95% CI, 0.78-2.03; P = .34).

CONCLUSIONS

ELF was associated with fibrosis stage in children who participated in TONIC. Although not associated with improvement in fibrosis, a decrease in ELF at EOT was associated with Nonalcoholic Steatohepatitis resolution and improvement in nonalcoholic fatty liver disease histology. ELF may be a useful noninvasive test to monitor treatment response in children with nonalcoholic fatty liver disease.

Clinical and Molecular Biomarkers for Diagnosis and Staging of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most common hepatic pathology in industrialized countries, affecting about 25% of the general population. NAFLD is a benign condition, however, it could evolve toward more serious diseases, including non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and finally, hepatocellular carcinoma (HCC). Liver biopsy is still the gold standard for NAFLD diagnosis. Due to the risks associated with liver biopsy and the impossibility to apply it on a large scale, it is now necessary to identify non-invasive biomarkers, which may reliably identify patients at higher risk of progression. Therefore, several lines of research have tried to address this issue by identifying novel biomarkers using omics approaches, including lipidomics, metabolomics and RNA molecules' profiling. Thus, in this review, we firstly report the conventional biomarkers used in clinical practice for NAFL and NASH diagnosis as well as fibrosis staging, and secondly, we pay attention to novel biomarkers discovered through omics approaches with a particular focus on RNA biomarkers (microRNAs, long-noncoding RNAs), showing promising diagnostic performance for NAFL/NASH diagnosis and fibrosis staging.

Diagnostic accuracy of fibrosis tests in children with non-alcoholic fatty liver disease: A systematic review

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in children. Even at young age, it can progress to liver fibrosis. Given the drawbacks of liver biopsy, there is a need for non-invasive methods to accurately stage liver fibrosis in this age group. In this systematic review, we evaluate the diagnostic accuracy of non-invasive methods for staging liver fibrosis in children with NAFLD.

METHODS

We searched MEDLINE, Embase, Web of Science and the Cochrane Library, for studies that evaluated the performance of a blood-based biomarker, prediction score or imaging technique in staging liver fibrosis in children with NAFLD, using liver biopsy as the reference standard.

RESULTS

Twenty studies with a total of 1787 NAFLD subjects were included, which evaluated three prediction scores, five simple biomarkers, two combined biomarkers and six imaging techniques. Most studies lacked validation. Substantial heterogeneity of studies and limited available study data precluded a meta-analysis of the few fibrosis tests evaluated in more than one study. The most consistent accuracy data were found for transient elastography by FibroScan®, ELF test and ultrasound elastography, with an area under the receiver operating characteristics curve varying between 0.92 and 1.00 for detecting significant fibrosis.

CONCLUSION

Due to the lack of validation, the accuracy and clinical utility of non-invasive fibrosis tests in children with NAFLD remains uncertain. As studies have solely been performed in tertiary care settings, accuracy data cannot directly be translated to screening populations.

Serum Biomarkers of Liver Fibrosis Staging in the Era of the Concept "Compensated Advanced Chronic Liver Disease"

Non-invasive indexes of liver fibrosis based on blood examinations have been developed for decades, partially replacing liver biopsy examinations. Recently, the concept of liver cirrhosis was revised and converted to “compensated advanced chronic liver diseases” since the Baveno VI consensus statement in 2015. The term “compensated advanced chronic liver diseases” was established based on the premise that serum biomarkers were not able to differentiate cirrhosis from severe fibrosis. The difficulty to histologically distinguish cirrhosis from severe fibrosis had been pointed out in 1977, when the definition and nomenclatures of cirrhosis had been determined by the World Health Organization. That was decades before serum biomarkers available at present were investigated. Though we are accustomed to differentiating the fibrosis stage as stage 1, 2, 3 (severe fibrosis), and 4 (cirrhosis), differentiation of cirrhosis from severe fibrosis is difficult even by histopathological examination. The current review will provide readers a framework to revise how to apply serum biomarkers on liver fibrosis staging in an era of the concept of “compensated advanced chronic liver disease”.

Systematic review: Accuracy of the enhanced liver fibrosis test for diagnosing advanced liver fibrosis and cirrhosis

BACKGROUND AND AIMS

The rising incidence of chronic liver disease (CLD) has increased the need for early recognition. This systematic review assesses the diagnostic accuracy of the enhanced liver fibrosis (ELF) test in cases of advanced fibrosis and cirrhosis due to multiple etiologies in at-risk populations.

METHODS

Studies evaluating the ELF accuracy in identifying advanced fibrosis or cirrhosis, defined as METAVIR stage F ≥ 3 and F = 4 or equivalent, in patients with non-alcoholic fatty liver disease (NAFLD), alcohol liver disease (ALD), or viral hepatitis were included. Liver biopsy was used as the reference standard. Medline and Embase databases were searched. The QUADAS-2 tool was used as a framework to assess risk of bias and applicability. The area under the receiver operator curve (AUROC) was extracted as a summary measure of diagnostic accuracy.

RESULTS

Thirty-six studies were included: 11 hepatitis C, 4 hepatitis B, 9 NAFLD, 2 ALD, and 10 mixed. The ELF test showed good diagnostic performance in detecting advanced fibrosis in patients with viral hepatitis (AUROC 0.69 to 0.98) and excellent performance in NAFLD (AUROC 0.78 to 0.97) and ALD (AUROC from 0.92 to 0.94). There is also evidence of good diagnostic performance for detecting cirrhosis in patients with viral hepatitis (AUROC 0.63 to 0.99), good performance in NAFLD (AUROC 0.85 to 0.92), and excellent performance in patients with ALD (AUROC 0.93 to 0.94).

CONCLUSION

This systematic review supports the use of the ELF test across a range of CLD as a possible alternative to liver biopsy in selected cases.

Non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has a global prevalence of 25% and is a leading cause of cirrhosis and hepatocellular carcinoma. NAFLD encompasses a disease continuum from steatosis with or without mild inflammation (non-alcoholic fatty liver), to non-alcoholic steatohepatitis (NASH), which is characterised by necroinflammation and faster fibrosis progression than non-alcoholic fatty liver. NAFLD has a bidirectional association with components of the metabolic syndrome, and type 2 diabetes increases the risk of cirrhosis and related complications. Although the leading causes of death in people with NAFLD are cardiovascular disease and extrahepatic malignancy, advanced liver fibrosis is a key prognostic marker for liver-related outcomes and overall mortality, and can be assessed with combinations of non-invasive tests. Patients with cirrhosis should be screened for hepatocellular carcinoma and oesophageal varices. There is currently no approved therapy for NAFLD, although several drugs are in advanced stages of development. Because of the complex pathophysiology and substantial heterogeneity of disease phenotypes, combination treatment is likely to be required for many patients with NAFLD. Healthy lifestyle and weight reduction remain crucial to the prevention and treatment of NAFLD.

Relationship of ELF and PIIINP With Liver Histology and Response to Vitamin E or Pioglitazone in the PIVENS Trial

Enhanced liver fibrosis score (ELF) and one of its components, amino-terminal propeptide of type III procollagen (PIIINP) are promising noninvasive biomarkers of liver histology in patients with nonalcoholic steatohepatitis (NASH). We evaluated the association of ELF and PIIINP with fibrosis stages at baseline and end of treatment (EOT) with vitamin E or pioglitazone in the PIVENS trial (Pioglitazone vs. Vitamin E vs. Placebo for the Treatment of Nondiabetic Patients With NASH) and characterized ELF and PIIINP changes and their associations with changes in the histological endpoints. ELF and PIIINP were measured at baseline and weeks 16, 48, and 96 on sera from 243 PIVENS participants. Baseline and EOT ELF were significantly associated with fibrosis stage (P < 0.001). The area under the curve for ELF's detection of clinically significant and advanced fibrosis in baseline biopsies was 0.74 and 0.79, respectively (P < 0.001). There was a significant drop in ELF score at weeks 48 and 96 in patients who achieved the NAFLD activity score (NAS)-based primary end point (P = 0.007) but not in those who experienced NASH resolution (P = 0.24) or fibrosis improvement (P = 0.50). Change in PIIINP was significantly associated with NASH resolution and improvement in NAS-based histological endpoint and fibrosis (P < 0.05 for all). Over the study period, both ELF and PIIINP significantly decreased with vitamin E (P < 0.05), but only PIIINP decreased with pioglitazone (P < 0.001). Conclusion: ELF is significantly associated with clinically significant and advanced fibrosis in patients with NASH, but its longitudinal changes were not associated with improvement in fibrosis or NASH resolution. PIIINP, one of its components, appears promising for identifying longitudinal histologic changes in patients with NASH and is worthy of further investigation.

The usefulness of noninvasive liver stiffness assessment using shear-wave elastography for predicting liver fibrosis in children

BACKGROUND

Pediatric patients with liver disease require noninvasive monitoring to evaluate the risk of fibrosis progression. This study aimed to identify the significant factors affecting liver stiffness values using two-dimensional shear-wave elastography (2D-SWE), and determine whether liver stiffness can predict the fibrosis stage of various childhood liver diseases.

METHODS

This study included 30 children (22 boys and 8 girls; mean age, 5.1 ± 6.1 years; range, 7 days-17.9 years) who had undergone biochemical evaluation, 2D-SWE examination, histopathologic analysis of fibrosis grade (F0 to F3), assessment of necroinflammatory activity, and steatosis grading between August 2016 and March 2020. The liver stiffness from 2D-SWE was compared between fibrosis stages using Kruskal-Wallis analysis. Factors that significantly affected liver stiffness were evaluated using univariate and multivariate linear regression analyses. The diagnostic performance was determined from the area under the receiver operating curve (AUC) values of 2D-SWE liver stiffness.

RESULTS

Liver stiffness at the F0-1, F2, and F3 stages were 7.9, 13.2, and 21.7 kPa, respectively (P < 0.001). Both fibrosis stage and necroinflammatory grade were significantly associated with liver stiffness (P < 0.001 and P = 0.021, respectively). However, in patients with alanine aminotransferase (ALT) levels below 200 IU/L, the only factor affecting liver stiffness was fibrosis stage (P = 0.030). The liver stiffness value could distinguish significant fibrosis (≥ F2) with an AUC of 0.950 (cutoff value, 11.3 kPa) and severe fibrosis (F3 stage) with an AUC of 0.924 (cutoff value, 18.1 kPa). The 2D-SWE values for differentiating significant fibrosis were 10.5 kPa (≥ F2) and 18.1 kPa (F3) in patients with ALT levels below 200 IU/L.

CONCLUSION

The liver stiffness values on 2D-SWE can be affected by both fibrosis and necroinflammatory grade and can provide excellent diagnostic performance in evaluating the fibrosis stage in various pediatric liver diseases. However, clinicians should be mindful of potential confounders, such as necroinflammatory activity or transaminase level, when performing 2D-SWE measurements for liver fibrosis staging.

Noninvasive stratification of nonalcoholic fatty liver disease by whole transcriptome cell-free mRNA characterization

Hepatic fibrosis stage is the most important determinant of outcomes in patients with nonalcoholic fatty liver disease (NAFLD). There is an urgent need for noninvasive tests that can accurately stage fibrosis and determine efficacy of interventions. Here, we describe a novel cell-free (cf)-mRNA sequencing approach that can accurately and reproducibly profile low levels of circulating mRNAs and evaluate the feasibility of developing a cf-mRNA-based NAFLD fibrosis classifier. Using separate discovery and validation cohorts with biopsy-confirmed NAFLD (n = 176 and 59, respectively) and healthy subjects (n = 23), we performed serum cf-mRNA RNA-Seq profiling. Differential expression analysis identified 2,498 dysregulated genes between patients with NAFLD and healthy subjects and 134 fibrosis-associated genes in patients with NAFLD. Comparison between cf-mRNA and liver tissue transcripts revealed significant overlap of fibrosis-associated genes and pathways indicating that the circulating cf-mRNA transcriptome reflects molecular changes in the livers of patients with NAFLD. In particular, metabolic and immune pathways reflective of known underlying steatosis and inflammation were highly dysregulated in the cf-mRNA profile of patients with advanced fibrosis. Finally, we used an elastic net ordinal logistic model to develop a classifier that predicts clinically significant fibrosis (F2-F4). In an independent cohort, the cf-mRNA classifier was able to identify 50% of patients with at least 90% probability of clinically significant fibrosis. We demonstrate a novel and robust cf-mRNA-based RNA-Seq platform for noninvasive identification of diverse hepatic molecular disruptions and for fibrosis staging with promising potential for clinical trials and clinical practice.NEW & NOTEWORTHY This work is the first study, to our knowledge, to utilize circulating cell-free mRNA sequencing to develop an NAFLD diagnostic classifier.

Protective effects of paclitaxel on thioacetamide-induced liver fibrosis in a rat model

Liver fibrosis is a public health burden that is highly associated with morbidity and mortality. Therefore, this study aims to explore the anti-fibrotic effects of low dose of paclitaxel (PTX) against thioacetamide (TAA)-induced liver fibrosis in rats and the possible mechanisms involved. TAA was administered at a dose of 200 mg/kg twice weekly for 6 weeks in rats to induce liver fibrosis similar to that in humans. Liver dysfunction was shown by increased alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transferase, along with histopathological changes. Liver fibrosis was confirmed by Masson's Trichome staining, increased collagen content, and elevated α-smooth muscle actin (α-SMA) protein expression. In addition, TAA induced liver apoptosis as indicated by the increased terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells in liver tissues. This study demonstrated that the administration of PTX (0.3 mg/kg/i.p.) three times a week for 6 weeks significantly alleviated functional and biochemical changes induced by TAA in addition to improving the liver architecture. PTX attenuated liver fibrosis as reflected by the decreased collagen content and α-SMA protein expression. Additionally, PTX attenuated liver apoptosis as indicated by the decreased TUNEL-positive cells. Moreover, PTX prevented TAA-induced elevation of transforming growth factor-β1 (TGF-β1), platelet-derived growth factor-BB (PDGF-BB), and tissue inhibitor of metalloproteinase 1 (TIMP-1) levels in liver tissues. These findings suggest that the low dose of PTX prevented TAA-induced liver fibrosis in rats, possibly by inhibiting the expression of TGF-β1 and PDGF-BB and subsequently suppressing the apoptosis and the expression of TIMP-1.

Noninvasive diagnostic tools for pediatric NAFLD: where are we now?

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of liver disease in the pediatric population. It is a significant liver complication of obesity that also prominently affects children. Over the past decade, several noninvasive methods have been investigated for replacing liver biopsy to identify which children with NAFLD have nonalcoholic steatohepatitis (NASH) and fibrosis. These methods that aim to differentiate the type and extent of liver damage are based on two main different methodologies: a 'biological' approach centered on the quantification of circulating biomarkers; and a 'physical' approach established by analyzing different imaging data.

AREAS COVERED

In this review, we illustrate the state of the art and recent discoveries on noninvasive methods for the diagnosis of NAFLD, NASH, and advanced fibrosis.

EXPERT OPINION

Currently, noninvasive tests cannot diagnose NASH or determine the degree of fibrosis. However, several lines of evidence have suggested that if these tests are used in a complementary way with other laboratory tests and imaging they have the potential to be used to monitor progression of disease and response to therapy in pediatric NAFLD. Future scientific research will focus on combining these methods with multiple potential predictors of genetic susceptibility.

A New Endemic of Concomitant Nonalcoholic Fatty Liver Disease and Chronic Hepatitis B

Hepatitis B virus (HBV) infection remains a global public problem despite the availability of an effective vaccine. In the past decades, nonalcoholic fatty liver disease (NAFLD) has surpassed HBV as the most common cause of chronic liver disease worldwide. The prevalence of concomitant chronic hepatitis B (CHB) and NAFLD thus reaches endemic proportions in geographic regions where both conditions are common. Patients with CHB and NAFLD are at increased risk of liver disease progression to cirrhosis and hepatocellular carcinoma. Due to the complexity of the pathogenesis, accurate diagnosis of NAFLD in CHB patients can be challenging. Liver biopsy is considered the gold standard for diagnosing and determining disease severity, but it is an invasive procedure with potential complications. There is a growing body of literature on the application of novel noninvasive serum biomarkers and advanced radiological modalities to diagnose and evaluate NAFLD, but most have not been adequately validated, especially for patients with CHB. Currently, there is no approved therapy for NAFLD, although many new agents are in different phases of development. This review provides a summary of the epidemiology, clinical features, diagnosis, and management of the NAFLD and highlights the unmet needs in the areas of CHB and NAFLD coexistence.

Appraising diagnostic performance of ELF test by pathological staging and digital quantification of liver fibrosis

INTRODUCTION AND OBJECTIVES

A crucial issue when appraising the performance of non-invasive markers is the limitations of the reference standard they are compared to. Digital image analysis (DIA) was suggested as a reproducible approach expressing fibrosis numerically as a proportionate area (PA) (%). We aimed to evaluate ELF test with direct reference to PA (%), thereby explore the improvement in accuracy to discriminate significant fibrosis which may actually have been underestimated by categorical pathological staging.

MATERIALS AND METHODS

PA (%) data were obtained by DIA of trichrome-stained liver biopsies of 52 chronic hepatitis patients. Paired serum samples of patients and additional 36 controls were performed to measure ELF test. Diagnostic performance characteristics of ELF test was derived in predicting significant fibrosis in the patient cohort, and also, in distinguishing healthy controls from patients with significant fibrosis.

RESULTS

We found an AUROC value of 0.73 for ELF to predict significant fibrosis as assessed by DIA and a lower AUROC value of 0.66 when assessed by conventional pathology. Importantly, ELF test provided considerably high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis defined by Ishak F≥2 and TPA≥5% (AUROCs 0.93 and 0.94, respectively) with optimal ELF cut-off point of 8.4 for both.

CONCLUSIONS

Digital quantification could represent a better reference standard than conventional pathology allowing a better discriminatory capability for ELF test. ELF test provided high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis suggesting a role as a screening strategy in the community setting.

Advances in the clinical use of collagen as biomarker of liver fibrosis

INTRODUCTION

Hepatic fibrosis is the excessive synthesis and deposition of extracellular matrix including collagen in the tissue. Chronic liver insult leads to progressive parenchymal damage, portal hypertension, and cirrhosis. Determination of hepatic collagen by invasive liver biopsy is the gold standard to estimate severity and stage of fibrosis. However, this procedure is associated with pain, carries the risk of infection and bleeding, and is afflicted with a high degree of sampling error. Therefore, there is urgent need for serological collagen-derived markers to assess collagen synthesis/turnover.

AREAS COVERED

Biochemical properties of collagens, cellular sources of hepatic collagen synthesis, and regulatory aspects in collagen expression. Markers are discussed suitable to estimate hepatic collagen synthesis and/or turnover. Discussed studies were identified through a PubMed search done in May 2020 and the authors' topic knowledge.

EXPERT OPINION

Hepatic fibrosis is mainly characterized by accumulation of collagen-rich scar tissue. Although traditionally performed liver biopsy is still standard in estimating hepatic fibrosis, there is evidence that noninvasive diagnostic scores and collagen-derived neo-epitopes provide clinical useful information. These noninvasive tests are less expensive than liver biopsy, better tolerated, safer, and more acceptable to patients. Therefore, these tests will lead to dramatic changes in diagnosis.

Enhanced liver fibrosis test for the non-invasive diagnosis of fibrosis in patients with NAFLD: A systematic review and meta-analysis

BACKGROUND & AIMS

The enhanced liver fibrosis (ELF) test has been proposed for the non-invasive assessment of advanced fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). We performed a systematic review to estimate the accuracy of this test against biopsy.

METHODS

In this systematic review, we searched MEDLINE, Embase, Web of Science and the Cochrane Library for studies that included patients with NAFLD and that used both liver biopsy (as the reference standard) and the ELF test. Two authors independently screened the references, extracted the data and assessed the quality of included studies. Due to the variation in reported thresholds, we used a multiple thresholds random effects model for meta-analysis (diagmeta R-package).

RESULTS

The meta-analysis of 11 studies reporting advanced fibrosis and 5 studies reporting significant fibrosis showed that the ELF test had a sensitivity of >0.90 for excluding fibrosis at a threshold of 7.7. However, as a diagnostic test at high thresholds, the test only achieved specificity and positive predictive value >0.80 in very high prevalence settings (>50%). To achieve a specificity of 0.90 for advanced and significant fibrosis, thresholds of 10.18 (sensitivity: 0.57) and 9.86 (sensitivity: 0.55) were required, respectively.

CONCLUSION

The ELF test showed high sensitivity but limited specificity to exclude advanced and significant fibrosis at low cut-offs. The diagnostic performance of the test at higher thresholds was found to be more limited in low-prevalence settings. We conclude that clinicians should carefully consider the likely disease prevalence in their practice setting and adopt suitable test thresholds to achieve the desired performance.

LAY SUMMARY

The enhanced liver fibrosis test has been suggested as a non-invasive blood test to aid the diagnosis of severe liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). Our study results showed that the test has a high negative predictive value, especially in populations with low disease prevalence (likely encountered in primary care); so, it can exclude advanced fibrosis in patients with NAFLD. However, when prevalence is low, the positive predictive value of the enhanced liver fibrosis test is low, suggesting that additional strategies may be needed to make a positive diagnosis in such settings.

Fighting liver fat

Non-alcoholic fatty liver disease is a chronic liver disease which is closely associated with components of the metabolic syndrome. Its high clinical burden results from the growing prevalence, inherent cardiometabolic risk and potential of progressing to cirrhosis. Patients with non-alcoholic fatty liver disease show variable rates of disease progression through a histological spectrum ranging from steatosis to steatohepatitis with or without fibrosis. The presence and severity of fibrosis are the most important prognostic factors in non-alcoholic fatty liver disease. This necessitates risk stratification of patients by fibrosis stage using combinations of non-invasive methods, such as composite scoring systems and/or transient elastography. A multidisciplinary approach to treatment is advised, centred on amelioration of cardiometabolic risk through lifestyle and pharmacological interventions. Despite the current lack of licensed, liver-targeted pharmacotherapy, several promising agents are undergoing late-phase clinical trials to complement standard management in patients with advanced disease. This review summarises the current concepts in diagnosis and disease progression of non-alcoholic liver disease, focusing on pragmatic approaches to risk assessment and management in both primary and secondary care settings.

Non-invasive detection of portal hypertension by enhanced liver fibrosis score in patients with different aetiologies of advanced chronic liver disease

BACKGROUND AND AIMS

The enhanced liver fibrosis (ELF) score comprises serum markers of fibrogenesis and matrix remodelling and was developed to detect liver fibrosis, however, it may also be useful for the non-invasive detection of portal hypertension (PHT).

METHODS

ELF score and its single components (TIMP1/PIIINP/HA) were analysed in 201 patients with advanced chronic liver disease (ACLD; ie hepatic venous pressure gradient (HVPG) ≥6 mm Hg). Patients with pre-/post-hepatic PHT, hepatocellular carcinoma beyond Milan criteria, and history of TIPS implantation or liver transplantation were excluded.

RESULTS

ELF and its single components correlated with HVPG in the overall cohort: ELF: r = .443, TIMP1: r = .368, PIIINP:r = .332, and HA:r = .419 (all P < .001). The strength of the correlation between ELF and HVPG decreased in higher HVPG strata: 6-9 mm Hg:r = .569(P = .004), 10-19 mm Hg:r = .304 (P = .001) and ≥20 mm Hg:r = -.023(P = .853). Area under the receiver operating characteristics (AUROC) of ELF score to detect clinically significant PHT (CSPH; HVPG ≥ 10 mm Hg) was 0.833. Importantly, HA alone yielded an AUROC of 0.828. Detection of CSPH in strictly compensated ACLD (cACLD) patients was less accurate: AUROC: 0.759 (P < .001). CSPH was ruled-in by ELF ≥ 11.1 with a PPV of 98% (sensitivity: 61%/specificity: 92%/NPV:24%), but CSPH could not be ruled-out. ELF score had a low AUROC of 0.677 (0.60-0.75; P < .001) for the diagnosis of high-risk PHT (HRPH; HVPG ≥ 20mm Hg) and, thus, HRPH could not be ruled-in by ELF. However, ELF < 10.1 ruled-out HRPH with a NPV of 95% (sensitivity: 97%/specificity: 26%/PPV: 39%).

CONCLUSION

The ELF score correlates with HVPG at values <20 mm Hg. An ELF ≥ 11.1 identifies patients with a high probability of CSPH, while an ELF < 10.1 may be used to rule-out HRPH.

Applying Non-Invasive Fibrosis Measurements in NAFLD/NASH: Progress to Date

Nonalcoholic fatty liver disease (NAFLD) has now become a worldwide health issue due to the obesity epidemic, affecting approximately 90% of the obese population and 15-40% of the general population. It is the most common form of chronic liver disease in the United States. NAFLD constitutes a spectrum of diseases ranging in severity from mild, such as fatty liver, progressing into nonalcoholic steatohepatitis (NASH), then fibrosis, and ending with cirrhosis. NASH and increasing fibrosis stage are associated with increased morbidity and mortality; the fibrosis stage is therefore a critical element of risk stratification needed to determine therapeutic approach and also the response to treatment. Liver biopsy is considered the 'gold standard' in the diagnosis of NAFLD. However, it is not practical for widespread clinical use because it is invasive, costly, and associated with complications including occasional death. These limitations have driven the development of noninvasive tests that can accurately predict the fibrosis stage in those with NAFLD. In this review, we provide a concise overview of different non-invasive measurements used for NAFLD/NASH.

The prevalence of liver fibrosis according to non-invasive tools in a pediatric home parenteral nutrition cohort

BACKGROUND & AIMS

Liver biopsy is no viable tool to routinely screen for liver fibrosis in children suffering from chronic intestinal failure (IF). We aim to assess the prevalence of liver fibrosis in a cohort of children with chronic IF by non-invasive tests: transient elastography (TE), aspartate-aminotransferase-to-platelet-ratio-index (APRI) and enhanced liver fibrosis (ELF) score.

METHODS

Cross sectional study where patients with chronic IF, receiving parenteral nutrition (PN) for at least 3 months, were enrolled. TE, APRI and ELF score were measured. Using Spearman's rank correlation coefficient and Kruskal-Wallis H test, the correlation between TE, APRI, ELF score and known risk factors for development of intestinal failure-associated liver disease (IFALD) were calculated.

RESULTS

32 patients were included (50% female), median age was 8 years and 4 months, median PN duration was 45 months. Six patients (21%) had TE ≥6.5 kPa, indicating significant fibrosis. Twelve patients (38%) had APRI ≥.5, indicating fibrosis. ELF score indicated moderate fibrosis in 17 patients (63%) and significant fibrosis in 10 patients (37%). TE and APRI correlated significantly with known risk factors for IFALD, but ELF showed poor correlation with known risk factors for IFALD.

CONCLUSION

In a cohort of pediatric patients suffering from chronic IF, TE measurement, APRI and ELF test show a varying, but substantial proportion of subjects with fibrosis. The diagnostic value of these tests and their role in the management of pediatric IF must be determined in larger cohorts with liver biopsy as reference standard.

TRIAL REGISTRATION

Academic Medical Center medical ethics committee number: METC 2017_185.

Accuracy of the Enhanced Liver Fibrosis test, and combination of the Enhanced Liver Fibrosis and non-invasive tests for the diagnosis of advanced liver fibrosis in patients with non-alcoholic fatty liver disease

AIM

The Enhanced Liver Fibrosis (ELF) test comprises a logarithmic algorithm combining three serum markers of hepatic extracellular matrix metabolism. We aimed to evaluate the performance of ELF for the diagnosis of liver fibrosis and to compare it with that of liver stiffness measurement (LSM) by FibroScan in non-alcoholic fatty liver disease.

METHODS

ELF cut-off values for the diagnosis of advanced fibrosis were obtained using receiver operating characteristic analysis in patients with biopsy-confirmed non-alcoholic fatty liver disease (training set; n = 200). Diagnostic performance was analyzed in the training set and in a validation set (n = 166), and compared with that of LSM in the FibroScan cohort (n = 224).

RESULTS

The area under receiver operating characteristic curve was 0.81 for the diagnosis of advanced fibrosis, and the ELF cut-off values were 9.34 with 90.4% sensitivity and 10.83 with 90.6% specificity in the training set, and 89.8% sensitivity and 85.5% specificity in the validation set. There was no significant difference in the area under the receiver operating characteristic curve between ELF and LSM (0.812 and 0.839). A combination of ELF (cut-off 10.83) and LSM (cut-off 11.45) increased the specificity to 97.9% and the positive predictive value, versus ELF alone. Sequential use of the Fibrosis-4 index (cut-off 2.67) and ELF (cut-off 9.34) increased the sensitivity to 95.9%.

CONCLUSIONS

ELF can identify advanced liver fibrosis in non-alcoholic fatty liver disease, and its diagnostic accuracy is comparable to that of FibroScan. According to the clinical setting, combinations or sequential procedures using other non-invasive tests complement the diagnostic performance of ELF for the identification of advanced fibrosis.

Serum biomarkers of fibrostenotic Crohn's disease: Where are we now?

Intestinal fibrosis and subsequent stricture formation are major clinical challenges in inflammatory bowel disease, resulting in an increased rate of operation and poor prognosis compared with those without. With the changing perception that intestinal fibrosis is irreversible to the point of view that it is reversible in recent years, various candidate serum biomarkers have been studied over the past decades, which may stratify patients based on their risks of developing stenosis and enable the detection of early stages of fibrosis. However, reliable and accurate biomarkers are still unavailable due to conflicting results and the lack of high-quality evidence. In this review we summarized the serum biomarkers that have been proposed for intestinal fibrosis in recent years, which includes gene polymorphisms or variants, epigenetic markers, extracellular matrix components, growth factors, and antibodies, aiming to provide clues for future research.

Nonalcoholic Fatty Liver Disease in Children: Unique Considerations and Challenges

Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence in concert with the global epidemic of obesity and is being diagnosed at increasingly younger ages. The unique histologic features and early presentation of disease in pediatrics suggest that children and adults may differ with regard to etiopathogenesis, with children displaying a greater vulnerability to genetic and environmental factors. Of significant relevance to pediatrics, in utero and perinatal stressors may alter the lifelong health trajectory of a child, increasing the risk of NAFLD and other cardiometabolic diseases. The development and progression of disease in childhood is likely to carry increased risk of long-term morbidity. Novel biomarkers and therapeutic agents are needed to avoid the otherwise inevitable health and societal consequences of this rapidly expanding pediatric population.

The Enhanced Liver Fibrosis test is associated with liver-related outcomes in postmenopausal women with risk factors for liver disease

BACKGROUND

Chronic liver disease (CLD) is usually asymptomatic but earlier detection is critical to permit life-saving interventions for those at risk due to high alcohol consumption and increased body mass index (BMI). The aim of this study was to estimate the association between the Enhanced Liver Fibrosis (ELF) test and liver-related events (LRE) and its performance in predicting LRE in postmenopausal women with risk factors in a nested case-control study within the United Kingdom Trial of Ovarian Cancer Screening (UKCTOCS).

METHODS

In a cohort of 95,126 we performed a case-control study measuring ELF in blinded samples from 173 participants with self-reported high alcohol use and / or BMI ≥25 kg/m2 comprising all 58 cases who developed LRE and 115 controls matched for age, alcohol and BMI who did not develop LRE during median follow-up of 8.5 years.

RESULTS

Using Cox regression at an ELF threshold of 10.51 hazard ratios (HR) for LRE were 4.88 (95% confidence interval (CI) 2.37-10.03) (unadjusted model) and 4.62 (95% CI 2.12-10.08) (adjusted for deprivation and self-reported hypertension, heart disease, hypercholesterolaemia and diabetes). At a threshold of 9.8 HR for LRE were 2.21 (95% CI 1.22-3.97) (unadjusted model) and 2.18 (95% CI 1.19-4.01) (adjusted). ELF was evaluated as a time dependent variable by generating time-dependent Cox models; HRs at an ELF threshold of 10.51 were 1.94 (95% CI 1.10-3.39) (unadjusted) and 2.05 (95% CI 1.16-3.64) (adjusted) and at a threshold of 9.8 HRs were 1.85 (95% CI 1.09-3.15) (unadjusted) and 1.80 (95% CI 1.04-3.13) (adjusted). Area under the receiver operating characteristic curve for recruitment ELF predicting LRE was 0.58 (95% CI 0.49-0.68), and for second subsequent ELF 0.61 (95% CI 0.52-0.71).

CONCLUSION

This study demonstrates the association between ELF and CLD in postmenopausal women with risk factors for liver disease, creating the opportunity to intervene to reduce liver-related mortality and morbidity. Although larger studies are required, these results demonstrate the potential of ELF as a prognostic tool in health checks in primary care.

TRIAL REGISTRATION

This study is nested in UKCTOCS. UKCTOCS is registered as an International Standard Randomised Controlled Trial, number ISRCTN22488978. Registered 06/04/2000.

Collagen biology and non-invasive biomarkers of liver fibrosis

There is an unmet need for high-quality liquid biomarkers that can safely and reproducibly predict the stage of fibrosis and the outcomes of chronic liver disease (CLD). The requirement for such markers has intensified because of the high global prevalence of diseases such as non-alcoholic fatty liver disease (NAFLD). In particular, there is a need for diagnostic and prognostic tools, as well as predictive biomarkers that reflect the efficacy of interventions, as described by the BEST criteria (Biomarkers, EndpointS, and other Tools Resource). This review covers the various liver collagens, their functional role in tissue homeostasis and delineates the common nomenclature for biomarkers based on BEST criteria. It addresses the common confounders affecting serological biomarkers, and describes defined collagen epitope biomarkers that originate from the dynamic processes of extracellular matrix (ECM) remodelling during liver injury.