Background: Three-dimensional (3D) MR elastography (MRE) derives viscoelastic parameters that may reflect inflammation, but their frequency dependence and the influence of steatosis on inflammation grading and fibrosis staging remain unclear.

Purpose: To investigate 3D multifrequency MRE for assessing hepatic inflammation, fibrosis stage across frequencies, and the influence of steatosis.

Study Type: Prospective.

Population: Sixty-four (40 men, median age: 58 years) participants with chronic liver disease (CLD); 21 (8 men, median age:28 years) healthy volunteers.

Field Strength/Sequence: 3-T; gradient-echo sequence with mechanical vibrations at low (16.7 and 18 Hz), medium (33.4 and 36 Hz), and high (50.1 and 54 Hz) frequencies.

Assessment: In CLD participants, MRE-derived viscoelastic parameters, shear stiffness, storage modulus, loss modulus, and damping ratio were compared with histologically assessed fibrosis, inflammation, and steatosis. MRE test–retest repeatability over 10 min was evaluated in healthy volunteers.

Statistical Tests: Wilcoxon rank sum test, Spearman's correlation, multivariable regression analysis, and area under the receiver operating curve (AUROC). A p value of < 0.05 was considered statistically significant.

Results: Inflammation was significantly independently associated with damping ratio at medium frequency, which showed moderate performance for grading inflammation (AUROC = 0.76–0.83, sensitivity = 0.83–0.84, specificity = 0.70–0.79). Fibrosis staging using shear stiffness and moduli showed high diagnostic performance (AUROC = 0.82–0.95), with comparable accuracy between medium and high frequencies (p = 0.327–0.896). Steatosis was not significantly correlated with MRE overall (p = 0.212–0.459), but was significantly associated with 19% higher stiffness and 20% higher loss modulus at medium frequency in CLD participants without fibrosis or inflammation.

Data Conclusion: Medium frequency 3D MRE demonstrated an independent association with inflammation while preserving accurate fibrosis assessment. Steatosis seemed not to confound MRE-based evaluation.

Level of Evidence: 1.

Technical Efficacy: Stage 2.

Plain Language Summary: Chronic liver disease can cause both inflammation and scarring (fibrosis). Accurate assessment usually requires a biopsy, which is invasive. This study evaluated a noninvasive imaging method called three-dimensional magnetic resonance elastography (3D MRE) in patients who underwent same-day liver biopsy. The researchers tested whether different vibration frequencies could detect inflammation and fibrosis. They found that medium frequency measurements were associated with liver inflammation while still accurately identifying fibrosis. Fat accumulation in the liver did not significantly affect the results. These findings suggest that 3D MRE may help medical doctors assess liver inflammation and fibrosis noninvasively in a single examination.

Background: Fibroblast activation protein (FAP) is a serine protease upregulated in liver and blood in patients with chronic liver disease of several etiologies. FAP has a pro-fibrotic effect and may also regulate disease progression by proteolytically affecting two circulating substrates, fibroblast growth factor 21 (FGF21) and alpha 2-antiplasmin (alpha 2AP). The aim of this study was to investigate the involvement of FAP in metabolic dysfunction-associated steatotic liver disease (MASLD). Methods: FAP protein levels were measured in liver biopsies (n = 47) and plasma samples (n = 79) from an extensively characterized longitudinal MASLD cohort. FAP-cleaved and -uncleaved forms of alpha 2AP were measured with a novel mass spectrometry-based method, using isotopically labeled recombinant protein fragments as internal standards. Total and intact FGF21 levels were quantified using ELISA. Results were correlated to histopathological steatosis grade, inflammation grade, ballooning grade and fibrosis stage. Results: Both liver and plasma levels of FAP were increased in patients with advanced fibrosis, stage 3-4 vs 0-2 (p &lt; 0.005) but were not affected by steatosis grade. The fraction of FAP-cleaved alpha 2AP correlated with the plasma FAP level and was significantly higher in patients with fibrosis stage 3-4 (p &lt; 0.05). In contrast, plasma FAP did not correlate with the ratio of intact FGF21. Conclusion: These results show that FAP expression is increased in more advanced hepatic fibrosis. This suggests that FAP might be involved in the pathophysiology of MASLD progression and could be a biomarker for advanced hepatic fibrosis. Studies in larger prospective cohorts are needed to confirm these findings.

Objective: Primary sclerosing cholangitis (PSC) is a rare broin ammatory hepatobiliary disease with a highly variable clinical course. Identifying patients at risk for poor outcomes remains challenging. Magnetic resonance imaging (MRI)-based approaches such as DiStrict, Anali score, and relative enhancement (RE) show promise but are limited by operator dependency or static measurements. This study explored pharmacokinetic modelling of liver function as a quantitative imaging biomarker for risk assessment in PSC.

Materials and methods: A prospective cohort of 26 PSC patients underwent up to ve annual MRI examinations with follow-up up to 7.5 years. Clinical endpoints included liver transplantation, decompensated cirrhosis, and cholangiocarcinoma. Correlation and receiver operating characteristics (ROC) analyses compared the pharmacokinetic model with Anali scores, RE, model for end-stage liver disease (MELD), and the Amsterdam–Oxford Model (AOM).

Results: The pharmacokinetic model (ksingle) correlated signi cantly with MELD (r = -0.429, p= 0.029), AOM (r = -0.557, p= 0.003), and endpoint events (r = -0.605, p= 0.001). ROC analysis showed excellent discrimination for ki,single (area under the curve [AUC]= 0.943) outperformed Anali scores (AUC= 0.800–0.829) and comparable to MELD (AUC= 0.857) and AOM (AUC= 0.900).

Conclusion: Pharmacokinetic liver function modelling correlated strongly with MELD and AOM, effectively identifying high-risk PSC patients.

Relevance statement: Pharmacokinetic liver function modelling detects functional impairment in PSC, correlating well with established tools such as the AOM. As an objective, quantitative imaging biomarker, this method may complement established risk scores and aid in the identi cation of patients at risk of adverse outcomes.

Key Points:

● Pharmacokinetic modelling estimates changes in liver function based on MRI.

● These estimates can be used as a prognostic tool in PSC.

● The model’s prognostic performance was comparable to established clinical tests.

ObjectivesMetabolic dysfunction-associated steatotic liver disease (MASLD) is associated with substantial clinical and economic burden. Fibrosis detection is key to disease management, but biopsy-defined staging is invasive, expensive, and associated with complications. We evaluated healthcare resource utilization (HCRU) and costs by disease stage using biopsy-defined staging and fibrosis-4 (FIB-4; a simple, well-validated, non-invasive tool for assessing fibrosis severity), and compared their utility for predicting long-term outcomes in MASLD.MethodsThis longitudinal observational cohort study included 959 adults with biopsy-defined MASLD in Swedish medical records (1974-2020) linked to national registers. Patients had a documented fibrosis stage (F0-F4) and age-stratified FIB-4 score (low, indeterminate, high) at baseline. All-cause, liver-, and cardiovascular (CV)-related HCRU/costs were evaluated. The predictive capacity of biopsy and FIB-4 for high HCRU (&gt;= 80th percentile of hospitalizations + outpatient visits) was assessed using Harrell's concordance index.ResultsIn general, patients with advanced fibrosis had significantly more all-cause and liver-related hospitalizations, longer length of stay, and higher costs than patients with less advanced fibrosis. The number and cost of liver-related outpatient visits increased significantly as fibrosis severity increased, a trend also observed when comparing high and low FIB-4 scores. Other HCRU/cost outcomes were inconsistent between scoring approaches. No association was found between CV-related HCRU and fibrosis severity. Biopsy and FIB-4 demonstrated similar predictive capacity for identifying patients with high HCRU.ConclusionsThese data highlight the positive association between fibrosis severity and HCRU and costs in MASLD, and suggest that FIB-4 may have similar utility to biopsy for evaluating certain HCRU outcomes.

ObjectivesPredicting disease progression in metabolic dysfunction-associated steatotic liver disease (MASLD) is challenging, and current non-invasive tests (NITs) lack the precision to replace liver biopsy. This study aimed to identify plasma biomarkers for different stages of fibrosis using affinity-based proteomics in two biopsy-proven cohorts. The primary objective was to identify biomarkers capable of distinguishing between low-to-no fibrosis (F0-1) and significant fibrosis (F2-4) in MASLD.Materials and methodsParticipants in the discovery cohort were recruited from Uppsala University Hospital and Swedish CArdioPulmonary bioImage Study (SCAPIS), while the validation cohort was included from Link & ouml;ping University Hospital. All participants diagnosed with MASLD underwent liver biopsy and were categorized by fibrosis stage (F0-1 or F2-4). A total of 276 plasma proteins were analyzed using Olink (R) panels, with biomarkers identified through ordinal logistic regression, random forest (RF) analysis and the Boruta algorithm.ResultsThe discovery cohort included 60 participants, with 60% having fibrosis stage F0-1 and 40% having F2-4. The validation cohort had 59 participants, of whom 35 had fibrosis stage F0-1 (59.3%) and 24 had stage F2-4 (40.7%). Five biomarkers were significantly associated with fibrosis stage in the discovery cohort, with four confirmed in the validation cohort. A model combining angiotensin converting enzyme-2 (ACE2), hepatocyte growth factor (HGF) and insulin-like growth factor-binding protein-7 (IGFBP-7) demonstrated strong predictive performance for significant fibrosis (c-statistics 0.82-0.83), outperforming fibrosis-4 (FIB-4) (c-statistics 0.61-0.72).ConclusionsA biomarker model including ACE2, HGF and IGFBP7 shows promise in distinguishing between low-stage and significant fibrosis.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver condition worldwide. There is an urgent need to develop new biomarkers to assess disease severity and to define patients with a progressive phenotype. Activin A is a new promising biomarker with conflicting results about liver fibrosis. In this study we investigate levels of Activin A in patients with biopsy proven MASLD. We assess levels of Activin A in regard to fibrosis stage and genetic variant I148M in the patatin-like phospholipase domain-containing protein 3 (PNPLA3). Methods: Activin A levels were assessed in plasma samples from patients with biopsy-proven MASLD in a cross-sectional study. All patients were clinically evaluated and the PNPLA3 I148M genotype of the cohort was assessed. Findings41 patients were included and 27% of these had advanced fibrosis. In MASLD patients with advanced fibrosis, Activin A levels was higher (p &lt; 0.001) and could classify advanced fibrosis with an AUROC for activin A of 0.836 (p &lt; 0.001). Patients homozygous for PNPLA3 I148M G/G had higher levels of activin A than non-homozygotes (p = 0.027). Conclusions: Circulating activin A levels were associated with advanced fibrosis and could be a potential blood biomarker for identifying advanced fibrosis in MASLD. Patients with the risk genotype PNPLA3 I148M G/G had higher levels of activin A proposing activin A as a contributor of the transition from simple steatosis to a fibrotic phenotype.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, encompasses steatosis and metabolic dysfunction-associated steatohepatitis (MASH), leading to cirrhosis and hepatocellular carcinoma. Preclinical MASLD research is mainly performed in rodents; however, the model that best recapitulates human disease is yet to be defined. We conducted a wide-ranging retrospective review (metabolic phenotype, liver histopathology, transcriptome benchmarked against humans) of murine models (mostly male) and ranked them using an unbiased MASLD 'human proximity score' to define their metabolic relevance and ability to induce MASH-fibrosis. Here, we show that Western diets align closely with human MASH; high cholesterol content, extended study duration and/or genetic manipulation of disease-promoting pathways are required to intensify liver damage and accelerate significant (F2+) fibrosis development. Choline- deficient models rapidly induce MASH-fibrosis while showing relatively poor translatability. Our ranking of commonly used MASLD models, based on their proximity to human MASLD, helps with the selection of appropriate in vivo models to accelerate preclinical research.

Background & aims: Long-term studies of the prognosis of NAFLD are scarce. Here, we investigated the risk of major adverse liver outcomes (MALO) in a large cohort of patients with NAFLD.

Methods: We conducted a cohort study with data from Swedish university hospitals. Patients (n = 1,260) with NAFLD without cirrhosis were diagnosed through biopsy or radiology, and had fibrosis estimated through vibration-controlled transient elastography, biopsy, or FIB-4 score between 1974 and 2020 and followed up through 2020. Each patient was matched on age, sex, and municipality with up to 10 reference individuals from the general population (n = 12,529). MALO were ascertained from Swedish national registers. The rate of events was estimated by Cox regression.

Results: MALO occurred in 111 (8.8%, incidence rate = 5.9/1,000 person-years) patients with NAFLD and 197 (1.6%, incidence rate = 1.0/1,000 person-years) reference individuals during a median follow up of 13 years. The rate of MALO was higher in patients with NAFLD (hazard ratio = 6.6; 95% CI = 5.2-8.5). The risk of MALO was highly associated with the stage of fibrosis at diagnosis. In the biopsy subcohort (72% of total sample), there was no difference in risk between patients with and without non-alcoholic steatohepatitis. The 20-year cumulative incidences of MALO were 2% for the reference population, 3% for patients with F0, and 35% for F3. Prognostic information from biopsy was comparable to FIB-4 (C-indices around 0.73 vs. 0.72 at 10 years).

Conclusions: This study provides updated information on the natural history of NAFLD, showing a high rate of progression to cirrhosis in F3 and a similar prognostic capacity of non-invasive tests to liver biopsy.

Impact and implications: Several implications for clinical care and future research may be noted based on these results. First, the risk estimates for cirrhosis development are important when communicating risk to patients and deciding on clinical monitoring and treatment. Estimates can also be used in updated health-economic evaluations, and for regulatory agencies. Second, our results again highlight the low predictive information obtained from ascertaining NASHstatus by histology and call for more objective means by which to define NASH. Such methods may include artificial intelligence-supported digital pathology. We highlight that NASH is most likely the causal factor for fibrosis progression in NAFLD, but the subjective definition makes the prognostic value of a histological NASH diagnosis of limited value. Third, the finding that prognostic information from biopsy and the very simple Fibrosis-4 score were comparable is important as it may lead to fewer biopsies and further move the field towards non-invasive means by which to define fibrosis and, importantly, use non-invasive tests as outcomes in clinical trials. However, all modalities had modest discriminatory capacity and new risk stratification systems are needed in NAFLD. Repeated measures of non-invasive scores may be a potential solution.

Background & Aims: Evidence for the benefit of scheduled imaging for early detection of hepatobiliary malignancies in primary sclerosing cholangitis (PSC) is limited. We aimed to compare different follow-up strategies in PSC with the hypothesis that regular imaging improves survival.

Methods: We collected retrospective data from 2975 PSC patients from 27 centres. Patients were followed from the start of scheduled imaging or in case of clinical follow-up from 1 January 2000, until death or last clinical follow-up alive. The primary endpoint was all-cause mortality.

Results: A broad variety of different follow-up strategies were reported. All except one centre used regular imaging, ultrasound (US) and/or magnetic resonance imaging (MRI). Two centres used scheduled endoscopic retrograde cholangiopancreatography (ERCP) in addition to imaging for surveillance purposes. The overall HR (CI95%) for death, adjusted for sex, age and start year of follow-up, was 0.61 (0.47-0.80) for scheduled imaging with and without ERCP; 0.64 (0.48-0.86) for US/MRI and 0.53 (0.37-0.75) for follow-up strategies including scheduled ERCP. The lower risk of death remained for scheduled imaging with and without ERCP after adjustment for cholangiocarcinoma (CCA) or high-grade dysplasia as a time-dependent covariate, HR 0.57 (0.44-0.75). Hepatobiliary malignancy was diagnosed in 175 (5.9%) of the patients at 7.9 years of follow-up. Asymptomatic patients (25%) with CCA had better survival if scheduled imaging had been performed.

Conclusions: Follow-up strategies vary considerably across centres. Scheduled imaging was associated with improved survival. Multiple factors may contribute to this result including early tumour detection and increased endoscopic treatment of asymptomatic benign biliary strictures.

Non-alcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome and is characterized by ectopic accumulation of triglycerides in the cytoplasm of hepatocytes, i.e., steatosis. NAFLD has become the most common chronic liver disease, with an estimated global prevalence of 25%. Although the majority of NAFLD patients will never experience liver-related complications, the progressive potential of NAFLD is indisputable, with 5-10% of subjects progressing to cirrhosis, end-stage liver disease, or hepatocellular carcinoma. NAFLD patients with advanced fibrosis are at the highest risk of developing cardiovascular and cirrhosis-related complications. Liver biopsy has hitherto been considered the reference method for evaluation of hepatic steatosis and fibrosis stage. Given the limitations of biopsy for widescale screening, non-invasive tests (NITs) for assessment of steatosis and fibrosis stage, including serum-based algorithms and ultrasound- and magnetic resonance-based methods, will play an increasing role in the management of NAFLD patients. This comprehensive review presents the advantages and limitations of NITs for identification of steatosis and advanced fibrosis in NAFLD. The clinical implications of using NITs to identify and manage NAFLD patients are also discussed.