New nomenclature for fatty liver disease.

This review investigates that, in 2023, fatty liver disease underwent a name change to "steatotic liver disease" (SLD). SLD now includes metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-related liver disease (ALD), and metabolic and alcohol-related liver disease (MetALD). The renaming aims to better incorporate alcohol intake and metabolic risk factors into disease classification and to diminish the stigma associated with the previous nomenclature. Early identification of the patient's aetiology is important for the prognosis which can be improved by interventions against the causative risk factors.

Paediatric steatotic liver disease has unique characteristics: A multisociety statement endorsing the new nomenclature.

Nonalcoholic fatty liver disease (NAFLD) has been a commonly used term and diagnosis in paediatric hepatology, gastroenterology, and endocrinology clinics for over 30 years. A multisociety Delphi process has determined a new name "Steatotic Liver Disease" (SLD) as the overarching term for disorders associated with hepatic lipid accumulation. Our Societies give our support to steatotic liver disease as the best overarching term for use in our communities. Metabolic dysfunction-associated steatotic liver disease (MASLD) overcomes many of the shortcomings of the name NAFLD. Here, we highlight several points of the new nomenclature that are of particular importance for our community and their consequences for implementation including: diagnostic criteria, considering alternate diagnoses, practical implementation, research, advocacy, and education for paediatricians. As with all nomenclature changes, it will take a concerted effort from our paediatric societies to help integrate the optimal use of this into practice.

Progress is impossible without change: understanding the evolving nomenclature of steatotic liver disease and its effect on hepatology practice.

The American, European, and Latin American liver societies have proposed a change in the nomenclature we use to describe alcohol-related liver disease and non-alcoholic fatty liver disease. Additionally, a term encompassing both is now advocated: steatotic liver disease, which includes metabolic dysfunction associated steatotic liver disease (MASLD) and MASLD with greater alcohol consumption (MetALD). These classifications offer increased relevance for clinicians, researchers, and patients alike. In this Viewpoint, we discuss the basis for this nomenclature shift and how it was developed. We also explore the challenges that will be faced in the adoption of such change. The proposed change seeks to banish stigma associated with phrasing such as alcoholic and fatty. However stigma, particularly related to the term fatty, is culturally nuanced, and reflects different entities depending on location. If such a change is internationally accepted, there will be wide-reaching effects on practitioners in primary care and metabolic medicine, and on patients. We discuss those effects and the opportunities the nomenclature change could offer, particularly for patients with alcohol and metabolic risk factors who represent a group previously ignored by clinical trials.

Detection of Frozen-Thawed Duck Fatty Liver by MALDI-TOF Mass Spectrometry: A Chemometrics Study.

The marketing of poultry livers is only authorized as fresh, frozen, or deep-frozen. The higher consumer demand for these products for a short period of time may lead to the marketing of frozen-thawed poultry livers: this constitutes fraud. The aim of this study was to design a method for distinguishing frozen-thawed livers from fresh livers. For this, the spectral fingerprint of liver proteins was acquired using Matrix-Assisted Laser Dissociation Ionization-Time-Of-Flight mass spectrometry. The spectra were analyzed using the chemometrics approach. First, principal component analysis studied the expected variability of commercial conditions before and after freezing-thawing. Then, the discriminant power of spectral fingerprint of liver proteins was assessed using supervised model generation. The combined approach of mass spectrometry and chemometrics successfully described the evolution of protein profile during storage time, before and after freezing-thawing, and successfully discriminated the fresh and frozen-thawed livers. These results are promising in terms of fraud detection, providing an opportunity for implementation of a reference method for agencies to fight fraud.

The Chinese Society of Hepatology position statement on the redefinition of fatty liver disease.

Fatty liver disease associated with metabolic dysfunction is of increasing concern in mainland China, the world's most populous country. The incidence of fatty liver disease is highest in China, surpassing the incidence in European countries and the USA. An international consensus panel recently published an influential report recommending a novel definition of fatty liver disease associated with metabolic dysfunction. This recommendation includes a switch in name from non-alcoholic fatty liver disease (NAFLD) to metabolic (dysfunction)-associated fatty liver disease (MAFLD) and adoption of a set of positive criteria for disease diagnosis that are independent of alcohol intake or other liver diseases. Given the unique importance of this proposal, the Chinese Society of Hepatology (CSH) invited leading hepatologists and gastroenterologists representing their respective provinces and cities to reach consensus on alternative definitions for fatty liver disease from a national perspective. The CSH endorses the proposed change from NAFLD to MAFLD (supported by 95.45% of participants). We expect that the new definition will result in substantial improvements in health care for patients and advance disease awareness, public health policy, and political, scientific and funding outcomes for MAFLD in China.

US-FLI score - Is it possible to predict the steatosis grade with an ultrasonographic score?

OBJECTIVES: A recent ultrasonographic score (Ultrasonographic fatty liver indicator (US-FLI)) allows to grade steatosis severity on ultrasound (US).We aimed to evaluate the agreement of US-FLI with the controlled attenuation parameter (CAP) in patients with non-alcoholic fatty liver disease (NAFLD). METHODS: Initially, inter-observer agreement for the score was assessed between 3 physicians using a sample of 31 patients.Later, 96 patients with NAFLD were included and several anthropometric/clinical/analytical parameters were assessed and US and transient elastography was performed. RESULTS: Physicians showed an excellent absolute agreement regarding the total score, with an average Interclass Correlation Coefficient of 0.972(95% CI 0.949-0.986). Comparing US-FLI with CAP, considering the previously defined cut-off for steatosis >S1(268dB/m) and > S2(280dB/m), US-FLI had a good discriminative capacity for both grades, with areas under the curve (AUC) of 0.88(p < 0.001) and 0.90(p < 0.001), respectively.Also, US-FLI ≤ 3 points had a negative predictive value of 100% for steatosis >S2 and US-FLI ≥6 points had a positive predictive value (PPV) of 94.0% for steatosis >S2. When comparing the clinical score Fatty Liver Index (FLI) for the same CAP cut-offs, it showed a weak discriminative capacity for both grades, with AUC of 0.65(p = 0.030) and 0.66(p = 0.017). AUC for US-FLI and FLI were significantly different for both cut-offs (p < 0.001). CONCLUSION: US-FLI has an excellent reproducibility and a good discriminative capacity for the different steatosis grades.Scores ≤3points exclude significant steatosis and scores ≥6 points have a PPV of 94,0% for steatosis >S2.US-FLI was significantly superior to the clinical score FLI in the discrimination between steatosis grades.

A new definition for metabolic dysfunction-associated fatty liver disease: An international expert consensus statement.

The exclusion of other chronic liver diseases including "excess" alcohol intake has until now been necessary to establish a diagnosis of metabolic dysfunction-associated fatty liver disease (MAFLD). However, given our current understanding of the pathogenesis of MAFLD and its rising prevalence, "positive criteria" to diagnose the disease are required. In this work, a panel of international experts from 22 countries propose a new definition for the diagnosis of MAFLD that is both comprehensive and simple, and is independent of other liver diseases. The criteria are based on evidence of hepatic steatosis, in addition to one of the following three criteria, namely overweight/obesity, presence of type 2 diabetes mellitus, or evidence of metabolic dysregulation. We propose that disease assessment and stratification of severity should extend beyond a simple dichotomous classification to steatohepatitis vs. non-steatohepatitis. The group also suggests a set of criteria to define MAFLD-associated cirrhosis and proposes a conceptual framework to consider other causes of fatty liver disease. Finally, we bring clarity to the distinction between diagnostic criteria and inclusion criteria for research studies and clinical trials. Reaching consensus on the criteria for MAFLD will help unify the terminology (e.g. for ICD-coding), enhance the legitimacy of clinical practice and clinical trials, improve clinical care and move the clinical and scientific field of liver research forward.

Prevalence of steatosis and fibrosis in young adults in the UK: a population-based study.

BACKGROUND: The estimated worldwide prevalence of non-alcoholic fatty liver disease (NAFLD) in adults is 25%; however, prevalence in young adults remains unclear. We aimed to identify the prevalence of steatosis and fibrosis in young adults in a sample of participants recruited through the Avon Longitudinal Study of Parents and Children (ALSPAC), based on transient elastography and controlled attenuation parameter (CAP) score. METHODS: In this population-based study, we invited active participants of the ALSPAC cohort to our Focus@24+ clinic at the University of Bristol (Bristol, UK) between June 5, 2015, and Oct 31, 2017, for assessment by transient elastography with FibroScan, to determine the prevalence of steatosis and fibrosis. FibroScan data were collected on histologically equivalent fibrosis stage (F0-F4) and steatosis grade (S0-S3); results with an IQR to median ratio of 30% or greater were excluded for median fibrosis results greater than 7·1 kPa, and CAP scores for steatosis were excluded if less than ten valid readings could be obtained. Results were collated with data on serology (including alanine aminotransferase, aspartate aminotransferase, and γ-glutamyl transferase) and exposures of interest: alcohol consumption (via the Alcohol Use Disorder Identification Test for Consumption [AUDIT-C] and the Diagnostic and Statistical Manual of Mental Disorders-5 criteria for alcohol use disorder), body-mass index (BMI), waist-to-height ratio, socioeconomic status (based on predefined ALSPAC markers), and sex. We used logistic regression models to calculate odds ratios (ORs) for the effect of exposures of interest on risk of steatosis and fibrosis, after dichotomising the prevalences of fibrosis and steatosis and adjusting for covariates (excessive alcohol intake [hazardous drinking, AUDIT-C score ≥5; or harmful drinking, evidence of alcohol use disorder], social class, smoking, and BMI). FINDINGS: 10 018 active ALSPAC participants were invited to our Focus@24+ clinic, and 4021 attended (1507 men and 2514 women), with a mean age of 24·0 years (IQR 23·0-25·0). 3768 CAP scores were eligible for analysis. 780 (20·7% [95% CI 19·4-22·0]) participants had suspected steatosis (S1-S3; ≥248 dB/m), with 377 (10·0%) presenting with S3 (severe) steatosis (≥280 dB/m). A BMI in the overweight or obese range was positively associated with steatosis when adjusted for excessive alcohol consumption, social class, and smoking (overweight BMI: OR 5·17 [95% CI 4·11-6·50], p<0·0001; obese BMI: 27·27 [20·54-36·19], p<0·0001). 3600 participants had valid transient elastography results for fibrosis analysis. 96 participants (2·7% [95% CI 2·2-3·2]) had transient elastography values equivalent to suspected fibrosis (F2-F4; ≥7·9 kPa), nine of whom had values equivalent to F4 fibrosis (≥11·7 kPa). Individuals with alcohol use disorder and steatosis had an increased risk of fibrosis when adjusted for smoking and social class (4·02 [1·24-13·02]; p=0·02). INTERPRETATION: One in five young people had steatosis and one in 40 had fibrosis around the age of 24 years. The risk of fibrosis appears to be greatest in young adults who have harmful drinking patterns and steatosis. A holistic approach to the UK obesity epidemic and excessive drinking patterns is required to prevent an increasing health-care burden of adults with advanced liver disease in later life. FUNDING: Medical Research Council UK, Alcohol Change UK, David Telling Charitable Trust.

Hounsfield unit values of liver pathologies in unenhanced post-mortem computed tomography.

BACKGROUND: The goal of this study was to evaluate if unenhanced PMCT HU values of liver pathologies differ from post-mortem HU values of non-pathologic liver tissue. METHODS: Liver HU values were measured in five liver segments in PMCT unenhanced datasets of 214 forensic cases (124 male, 90 female, mean age 54.3 years). Liver HU values were compared with corresponding histologic liver findings. HU values of non-pathologic livers were compared to HU values of liver pathologies. RESULTS: A total of 64 non-pathologic livers (mean HU 58.32, SD 8.91) were assessed. Histologic diagnosed liver pathologies were as follows: steatosis (n = 121 (grade I n = 61, grade II n = 37, grade III n = 23)), fibrosis (n = 10), and cirrhosis (n = 19). HU values of the livers exhibiting severe steatosis (mean HU 32.44, SD 13.76), fibrosis (mean HU 44.7, SD 16.31), and cirrhosis (mean HU 50.59, SD 9.42) significantly differed to HU values of non-pathologic livers at ANOVA testing. CONCLUSION: PMCT unenhanced liver HU value measurements may be used as an additional method to detect unspecific liver-pathology. Values below 30 HU may specifically indicate severe steatosis.

Staging of Fatty Liver Diseases Based on Hierarchical Classification and Feature Fusion for Back-Scan-Converted Ultrasound Images.

Fatty liver disease is progressive and may not cause any symptoms at early stages. This disease is potentially fatal and can cause liver cancer in severe stages. Therefore, diagnosing and staging fatty liver disease in early stages is necessary. In this paper, a novel method is presented to classify normal and fatty liver, as well as discriminate three stages of fatty liver in ultrasound images. This study is performed with 129 subjects including 28 normal, 47 steatosis, 42 fibrosis, and 12 cirrhosis images. The proposed approach uses back-scan conversion of ultrasound sector images and is based on a hierarchical classification. The proposed algorithm is performed in two parts. The first part selects the optimum regions of interest from the focal zone of the back-scan-converted ultrasound images. In the second part, discrimination between normal and fatty liver is performed and then steatosis, fibrosis, and cirrhosis are classified in a hierarchical basis. The wavelet packet transform and gray-level co-occurrence matrix are used to obtain a number of statistical features. A support vector machine classifier is used to discriminate between normal and fatty liver, and stage fatty cases. The results of the proposed scheme clearly illustrate the efficiency of this system with overall accuracy of 94.91% and also specificity of more than 90%.

Molecular classification of fatty liver by high-throughput profiling of protein post-translational modifications.

We describe an alternative approach to classifying fatty liver by profiling protein post-translational modifications (PTMs) with high-throughput capillary isoelectric focusing (cIEF) immunoassays. Four strains of mice were studied, with fatty livers induced by different causes, such as ageing, genetic mutation, acute drug usage, and high-fat diet. Nutrient-sensitive PTMs of a panel of 12 liver metabolic and signalling proteins were simultaneously evaluated with cIEF immunoassays, using nanograms of total cellular protein per assay. Changes to liver protein acetylation, phosphorylation, and O-N-acetylglucosamine glycosylation were quantified and compared between normal and diseased states. Fatty liver tissues could be distinguished from one another by distinctive protein PTM profiles. Fatty liver is currently classified by morphological assessment of lipid droplets, without identifying the underlying molecular causes. In contrast, high-throughput profiling of protein PTMs has the potential to provide molecular classification of fatty liver.

Utility and appropriateness of the fatty liver inhibition of progression (FLIP) algorithm and steatosis, activity, and fibrosis (SAF) score in the evaluation of biopsies of nonalcoholic fatty liver disease.

UNLABELLED: Biopsy is still the gold standard for the diagnosis of nonalcoholic steatohepatitis but the definition may vary among pathologists, a drawback especially in evaluation of biopsies for clinical trials. We previously developed a scoring system (steatosis, activity, fibrosis [SAF]) allowing the use of an algorithm (fatty liver inhibition of progression [FLIP]) for the classification of liver injury in morbid obesity. The aim of this study was to determine whether the use of the SAF score and FLIP algorithm can decrease interobserver variations among pathologists. In a first session, pathologists categorized 40 liver biopsies of patients with nonalcoholic fatty liver disease (NAFLD) according to their own experience. In a second reading session, each pathologist reclassified the same slides by using the FLIP algorithm and SAF score, blinded to their first evaluation. The experiment was repeated with two different groups of pathologists at varying levels of training in liver pathology. The percentage of biopsy interpretation concordant with reference evaluation increased from 77% to 97% in Group 1 and from 42% to 75% in Group 2 after the use of the SAF score and FLIP algorithm. The strength of concordance in classification increased in Group 1 from moderate (κ = 0.54) to substantial (κ = 0.66) and from fair (κ = 0.35) to substantial (κ = 0.61) in Group 2 with application of the algorithm. With regard to the SAF score, concordance was substantial in Group 1 for steatosis (κ = 0.61), activity (κ = 0.75), and almost perfect for fibrosis (κ = 0.83 after pooling 1a, 1b, and 1c together into a single score F1). Similar trends were observed in Group 2 (κ = 0.54 for S, κ = 0.68 for A, and κ = 0.72 for F). CONCLUSION: The FLIP algorithm based on the SAF score should decrease interobserver variations among pathologists and are likely to be implemented in pathology practice.

Automatic classification of white regions in liver biopsies by supervised machine learning.

Automated assessment of histological features of non-alcoholic fatty liver disease (NAFLD) may reduce human variability and provide continuous rather than semiquantitative measurement of these features. As part of a larger effort, we perform automatic classification of steatosis, the cardinal feature of NAFLD, and other regions that manifest as white in images of hematoxylin and eosin-stained liver biopsy sections. These regions include macrosteatosis, central veins, portal veins, portal arteries, sinusoids and bile ducts. Digital images of hematoxylin and eosin-stained slides of 47 liver biopsies from patients with normal liver histology (n = 20) and NAFLD (n = 27) were obtained at 20× magnification. The images were analyzed using supervised machine learning classifiers created from annotations provided by two expert pathologists. The classification algorithm performs with 89% overall accuracy. It identified macrosteatosis, bile ducts, portal veins and sinusoids with high precision and recall (≥ 82%). Identification of central veins and portal arteries was less robust but still good. The accuracy of the classifier in identifying macrosteatosis is the best reported. The accurate automated identification of macrosteatosis achieved with this algorithm has useful clinical and research-related applications. The accurate detection of liver microscopic anatomical landmarks may facilitate important subsequent tasks, such as localization of other histological lesions according to liver microscopic anatomy.