Noninvasive imaging biomarkers for liver fibrosis in nonalcoholic fatty liver disease: current and future

Agile 3+ and Agile 4 scores predict chronic kidney disease development in metabolic dysfunction-associated steatotic liver disease

BACKGROUND AND AIMS

Despite the development of transient elastography (TE)-based Agile scores for diagnosing fibrotic burden in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), their applicability in predicting kidney outcomes remains unclear. We aimed to investigate the association between liver fibrotic burden, as assessed by Agile scores, and the risk of incident chronic kidney disease (CKD) in patients with MASLD.

METHODS

A total of 3240 participants with MASLD but without pre-existing CKD who underwent TE between July 2006 and October 2018 were selected. The primary outcome was incident CKD, defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 or proteinuria (≥1+ on dipstick) on two consecutive measurements. The secondary outcome was a 25% decline in eGFR measured on two consecutive visits.

RESULTS

During a median follow-up of 3.6 years, 187 participants (5.8%) developed incident CKD. When stratified into three groups according to Agile 3+ scores, multivariable Cox models revealed that risk of incident CKD was 2.77-fold (95% confidence interval [CI], 1.89-4.07; p < 0.001) higher in the high-risk group (Agile 3+ >0.68), compared to the low-risk group (Agile 3+ <0.45). During a median follow-up of 3.4 years, the high-risk group had a 2.41-fold higher risk (95% CI, 1.86-3.12; p < 0.001) of experiencing the secondary outcome, compared to the low-risk group. Similar findings were observed for Agile 4 scores. Prediction testing revealed that Agile scores were better predictors of kidney outcomes, compared to liver stiffness measured by TE.

CONCLUSIONS

In patients with MASLD, but without CKD, advanced liver fibrosis measured by Agile scores was significantly associated with a higher risk of incident CKD.

Non-invasive Scores and Serum Biomarkers for Fatty Liver in the Era of Metabolic Dysfunction-associated Steatotic Liver Disease (MASLD): A Comprehensive Review From NAFLD to MAFLD and MASLD

PURPOSE OF REVIEW

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rapidly increasing worldwide, making it the leading cause of liver related morbidity and mortality. Currently, liver biopsy is the gold standard for assessing individuals with steatohepatitis and fibrosis. However, its invasiveness, sampling variability, and impracticality for large-scale screening has driven the search for non-invasive methods for early diagnosis and staging. In this review, we comprehensively summarise the evidence on the diagnostic performance and limitations of existing non-invasive serum biomarkers and scores in the diagnosis and evaluation of steatosis, steatohepatitis, and fibrosis.

RECENT FINDINGS

Several non-invasive serum biomarkers and scores have been developed over the last decade, although none has successfully been able to replace liver biopsy. The introduction of new NAFLD terminology, namely metabolic dysfunction-associated fatty liver disease (MAFLD) and more recently metabolic dysfunction-associated steatotic liver disease (MASLD), has initiated a debate on the interchangeability of these terminologies. Indeed, there is a need for more research on the variability of the performance of non-invasive serum biomarkers and scores across the diagnostic entities of NAFLD, MAFLD and MASLD. There remains a significant need for finding valid and reliable non-invasive methods for early diagnosis and assessment of steatohepatitis and fibrosis to facilitate prompt risk stratification and management to prevent disease progression and complications. Further exploration of the landscape of MASLD under the newly defined disease subtypes is warranted, with the need for more robust evidence to support the use of commonly used serum scores against the new MASLD criteria and validation of previously developed scores.

New Biomarkers in Liver Fibrosis: A Pass through the Quicksand?

Chronic liver diseases (CLD) stem from various causes and lead to a gradual progression that ultimately may result in fibrosis and eventually cirrhosis. This process is typically prolonged and asymptomatic, characterized by the complex interplay among various cell types, signaling pathways, extracellular matrix components, and immune responses. With the prevalence of CLD increasing, diagnoses are often delayed, which leads to poor prognoses and in some cases, the need for liver transplants. Consequently, there is an urgent need for the development of novel, non-invasive methods for the diagnosis and monitoring of CLD. In this context, serum biomarkers-safer, repeatable, and more acceptable alternatives to tissue biopsies-are attracting significant research interest, although their clinical implementation is not yet widespread. This review summarizes the latest advancements in serum biomarkers for detecting hepatic fibrogenesis and advocates for concerted efforts to consolidate current knowledge, thereby providing patients with early, effective, and accessible diagnoses that facilitate personalized therapeutic strategies.

Advances in Noninvasive Molecular Imaging Probes for Liver Fibrosis Diagnosis

Liver fibrosis is a wound-healing response to chronic liver injury, which may lead to cirrhosis and cancer. Early-stage fibrosis is reversible, and it is difficult to precisely diagnose with conventional imaging modalities such as magnetic resonance imaging, positron emission tomography, single-photon emission computed tomography, and ultrasound imaging. In contrast, probe-assisted molecular imaging offers a promising noninvasive approach to visualize early fibrosis changes in vivo, thus facilitating early diagnosis and staging liver fibrosis, and even monitoring of the treatment response. Here, the most recent progress in molecular imaging technologies for liver fibrosis is updated. We start by illustrating pathogenesis for liver fibrosis, which includes capillarization of liver sinusoidal endothelial cells, cellular and molecular processes involved in inflammation and fibrogenesis, as well as processes of collagen synthesis, oxidation, and cross-linking. Furthermore, the biological targets used in molecular imaging of liver fibrosis are summarized, which are composed of receptors on hepatic stellate cells, macrophages, and even liver collagen. Notably, the focus is on insights into the advances in imaging modalities developed for liver fibrosis diagnosis and the update in the corresponding contrast agents. In addition, challenges and opportunities for future research and clinical translation of the molecular imaging modalities and the contrast agents are pointed out. We hope that this review would serve as a guide for scientists and students who are interested in liver fibrosis imaging and treatment, and as well expedite the translation of molecular imaging technologies from bench to bedside.

Point Shear Wave Elastography for Splenic Assessment: A Comparative Study of Splenomegaly and Normal Spleens

Background The spleen, a key immunological organ, plays a crucial role in filtering aged or damaged red blood cells. Splenomegaly, an enlargement of the spleen, can arise from a variety of physiological and pathological conditions, including hematological disorders, hepatic diseases, and infections. Accurate diagnosis and evaluation of splenomegaly are essential for effective treatment. Objectives The objective of this study was to evaluate splenic stiffness in patients with splenomegaly using point shear wave elastography (pSWE) and compare the findings with those of individuals with normal spleen. Materials and methods This hospital-based observational study was conducted at Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, India, from October 2022 to December 2023. The study included 56 participants, divided into two groups: 28 patients with splenomegaly and 28 healthy controls. Spleen stiffness was measured using a Samsung HS70A ultrasound machine (Samsung Electronics Pvt. Ltd., Seoul, South Korea), and pSWE was performed with a curvilinear probe. Data were analyzed using IBM SPSS Statistics for Windows, Version 26.0 (Released 2019; IBM Corp., Armonk, New York, United States), and the significance of differences was assessed using an independent t-test with a p-value of <0.05, considered statistically significant. Results The mean spleen stiffness, measured in kilopascals (kPa), was significantly higher in individuals with splenomegaly (32.05 ± 12.54 kPa) compared to controls (22.9 ± 9.49 kPa) (p = 0.003). A positive correlation (rho = 0.482, p < 0.001) was observed between spleen diameter and spleen stiffness. Conclusion This study demonstrates that pSWE is an effective, non-invasive tool for assessing spleen stiffness. The higher spleen stiffness in splenomegaly patients underscores pSWE's diagnostic utility, with a positive correlation between spleen diameter and stiffness. Further multi-center studies are recommended to validate these findings, highlighting pSWE's promise in evaluating and monitoring splenic disorders.

TyG-GGT is a Reliable Non-Invasive Predictor of Advanced Liver Fibrosis in Overweight or Obese Individuals

BACKGROUND

Liver fibrosis is a predisposing factor for liver cancer. This study will investigate the predictive role of the Triglyceride-glucose and Gamma-glutamyl transferase index (TyG-GGT) as a non-invasive indicator of advanced liver fibrosis in individuals with obesity or overweight.

METHOD

We enrolled patients who underwent metabolic and bariatric surgery as well as intraoperative liver biopsies at Zhejiang provincial people's hospital from August 2020 to March 2023. Clinical characteristics, comorbidities, laboratory data, and pathological variables of patients were collected and analysed. Then, we conducted logistics regression model to compare the performance of the TyG-GGT index with other 4 non-invasive models.

RESULTS

A total of 65 patients were included in this study. 43(66.2%) of them were female, with the mean body mass index (BMI) of 39.0 ± 7.3 kg/m2. Meanwhile, 24(36.9%) patients were diagnosed with diabetes. Advanced liver fibrosis were observed in 16.9% of patients, while liver cirrhosis was found in 4.6% of patients. The multivariable logistics regression showed that TyG-GGT was an independent risk factor of advanced liver fibrosis (OR = 6.989, P = 0.049). Additionally, compared to another 4 non-invasive liver fibrosis models (NFS = 0.66, FIB4 = 0.65, METS-IR = 0.68, APRI = 0.65), TyG-GGT exhibits the highest AUC value of 0.75.

CONCLUSIONS

More than one-third of patients undergoing metabolic and bariatric surgery are afflicted with nonalcoholic steatohepatitis (NASH), and a significant proportion exhibit advanced fibrosis. TyG-GGT was a potentially reliable predictor for screening individuals with overweight or obesity at high risk of advanced liver fibrosis, thus providing clinical guidance for early intervention in this targeted group.

Performance of noninvasive seromarkers in predicting liver fibrosis among MAFLD patients with or without viral hepatitis

The accuracy of noninvasive seromarkers in predicting liver fibrosis in metabolic dysfunction-associated fatty liver disease (MAFLD) patients with or without viral hepatitis is elusive. The AST to platelet ratio index (APRI), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS) were assessed in 871 MAFLD patients who received elastography in a viral hepatitis-endemic area. The area under the receiver operating characteristic (AUROC) curve increased substantially with increasing fibrotic stage across the three biomarkers. APRI (AUROC range 0.73-0.80) and FIB-4 (AUROC range 0.66-0.82) performed better than NFS (AUROC range 0.63-0.75). When patients were divided into viral and non-viral MAFLD groups, a better AUROC of APRI (range 0.76-0.80) and FIB-4 (range 0.68-0.78) than NFS (range 0.62-70) existed only in viral MALFD but not in non-viral MAFLD. Regarding the NFS, the AUROC was higher in non-viral MAFLD (range 0.69-0.86) and outperformed viral MAFLD at all fibrotic stages. The accuracy in predicting liver fibrosis increased with the advancement of liver disease for the three biomarkers. NFS exerted better diagnostic accuracy in non-viral than in viral MAFLD patients across different fibrotic stages. The best accuracy was 91.1% using the cutoff value of -9.98 for the NFS in predicting liver cirrhosis in non-viral MAFLD patients. The APRI and FIB-4 performed better than the NFS in predicting liver fibrosis in MAFLD as a whole. The suboptimal performance and accuracy of the NFS existed only in viral MAFLD patients. Caution should be taken when assessing the NFS in MAFLD patients with viral hepatitis.

Proposal of a Novel Serological Algorithm Combining FIB-4 and Serum M2BPGi for Advanced Fibrosis in Nonalcoholic Fatty Liver Disease

Background/Aims

Noninvasive methods have become increasingly critical in the diagnosis of fibrosis in chronic liver diseases. Herein, we compared the diagnostic performance of serum Mac2 binding protein glycosylation isomer (M2BPGi) and other serological panels for fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and proposed an improved two-step diagnostic algorithm for advanced fibrosis.

Methods

We enrolled 231 patients diagnosed with NAFLD who underwent a liver biopsy. We subsequently evaluated the diagnostic performance of serological panels, including serum M2BPGi, a fibrosis index based on four factors (FIB-4), aspartate aminotransferase-to-platelet ratio index (APRI), and NAFLD fibrosis score (NFS), in predicting the stage of liver fibrosis. We then constructed a two-step algorithm to better differentiate advanced fibrosis.

Results

The areas under the receiver operating characteristic curves of serum M2BPGi, FIB-4, APRI, and NFS for advanced fibrosis (≥F3) were 0.823, 0.858, 0.779, and 0.827, respectively. To reduce the performance of unnecessary liver biopsy, we propose a two-step algorithm using FIB-4 as an initial diagnostic tool and serum M2BPGi (≥0.6) as an additional diagnostic method for patients classified as intermediate (23%). Using the proposed algorithm, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 0.812, 0.814, 0.814, 0.600, and 0.927, respectively.

Conclusions

Serum M2BPGi is a simple and effective test for advanced fibrosis in patients with NAFLD. Application of the two-step algorithm based on FIB-4 and M2BPGi proposed here can improve diagnostic performance and reduce unnecessary tests, making diagnosis easily accessible, especially in primary medical centers.

The Portal Venous Pulsatility Index and Main Portal Vein Diameter as Surrogate Markers for Liver Fibrosis in Nonalcoholic Fatty Liver Disease and Metabolic-Dysfunction-Associated Steatotic Liver Disease

(1) Background: Despite numerous noninvasive methods for assessing liver fibrosis, effective ultrasound parameters remain limited. We aimed to identify easily measurable ultrasound parameters capable of predicting liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and metabolic-dysfunction-associated steatotic liver disease (MASLD); (2) Methods: The data of 994 patients diagnosed with NAFLD via ultrasound at the Armed Forces Goyang Hospital were retrospectively collected from June 2022 to July 2023. A liver stiffness measurement (LSM) ≥ 8.2 kPa was classified as significant fibrosis. Liver steatosis with cardiometabolic risk factors was defined as MASLD. Two ultrasound variables, the portal venous pulsatility index (VPI) and main portal vein diameter (MPVD), were measured; (3) Results: Of 994 patients, 68 had significant fibrosis. Significant differences in VPI (0.27 vs. 0.34, p < 0.001) and MPVD (10.16 mm vs. 8.98 mm, p < 0.001) were observed between the fibrotic and non-fibrotic groups. A logistic analysis adjusted for age and body mass index (BMI) revealed that only VPI (OR of 0.955, p = 0.022, VPI on a 0.01 scale) and MPVD (OR of 1.501, p < 0.001) were significantly associated with significant liver fibrosis. In the MASLD cohort (n = 939), VPI and MPVD were associated with significant fibrosis. To achieve better accuracy in predicting liver fibrosis, we established a nomogram that incorporated MPVD and VPI. The established nomogram was validated in the test cohort, yielding an area under the receiver operating characteristic curve of 0.821 for detecting significant liver fibrosis; (4) Conclusions: VPI and MPVD, as possible surrogate markers, are useful in predicting significant fibrosis in patients with NAFLD and MASLD.

Novel noninvasive indices for the assessment of liver fibrosis in primary biliary cholangitis

The present study aimed to investigate the accuracy of new noninvasive markers in predicting liver fibrosis among individuals with primary biliary cholangitis (PBC). This retrospective analysis included subjects with PBC who had liver biopsies. Scheuer's classification was used to determine the fibrosis stage. The bilirubin to albumin (Alb) ratio (BAR), fibrosis index based on the four factors (FIB-4), γ-glutamyl transpeptidase to platelet (PLT) ratio (GPR), red cell distribution width to PLT ratio (RPR), aspartate aminotransferase (AST) to alanine aminotransferase ratio (AAR), AST to PLT ratio index (APRI) and total bilirubin to PLT ratio (TPR) were calculated based on the laboratory parameters. A novel index called BARP was conceived as BAR x RPR. A total of 78 individuals with PBC were included in the study, 84.6% of whom had significant fibrosis, 30.8% had advanced fibrosis and 15.4% had cirrhosis. In the multivariate analysis, Alb was determined to be an independent predictor of advanced fibrosis (odds ratio=0.823, P=0.034). The area under the receiver operating characteristic curves (AUROCs) of the BAR, GPR, TPR and BARP were statistically significant in predicting severe fibrosis (P<0.05) and were 0.747, 0.684, 0.693 and 0.696, respectively. In assessing advanced fibrosis, the AUROCs for the AAR, APRI, BAR, FIB-4, RPR, TPR and BARP were 0.726, 0.650, 0.742, 0.716, 0.670, 0.735 and 0.750, respectively. The AUROCs for the APRI, BAR, FIB-4, RPR, TPR and BARP for cirrhosis prediction were 0.776, 0.753, 0.821, 0.819, 0.808 and 0.832, respectively. By comparing the AUROCs, it was demonstrated that the diagnostic capabilities of the BARP (P=0.021) and TPR (P=0.044) were superior to those of the APRI in predicting advanced fibrosis. In conclusion, the BAR, BARP and TPR were of predictive value for the grade of liver fibrosis in PBC and Alb had a diagnostic value in identifying early fibrosis. The aforementioned noninvasive indices may be used for predicting histologic stages of PBC.

The interplay of metabolic dysfunction-associated fatty liver disease and viral hepatitis on liver disease severity: A large community-based study in a viral endemic area

BACKGROUND AND AIM

The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) and its interplay with hepatitis B virus (HBV) and hepatitis C virus (HCV) in terms of liver disease severity is elusive.

METHODS

A mass surveillance program was conducted in a viral hepatitis endemic area. The objective was to identify MAFLD/non-MAFLD subjects with advanced liver disease.

RESULTS

Two thousand two hundred and forty-two (41.7%) of the 5378 subjects were identified as having MAFLD, and 375 (7.0%) had advanced liver disease. The proportions of anti-HCV and HBsAg seropositivity were 19.3% and 9.7%, respectively. The proportions of advanced fibrosis in subjects with non-viral hepatitis (NBNC), HBV and HCV infection were 2.8%, 5.7% and 23.4%, respectively. Subjects with MAFLD had a significantly higher proportion of advanced fibrosis (8.7% vs 5.7%, P < 0.001). Factors associated with advanced fibrosis included age (odds ratio [OR]/95% confidence interval [CI]: 4.8/3.7-6.0, P < 0.001), male sex (OR/CI: 1.3/1.0-1.7, P = 0.019), anti-HCV seropositivity (OR/CI: 5.9/4.6-7.5, P = 0.019), MAFLD-lean metabolic dysregulation (MS) (OR/CI: 2.6/1.3-5.2, P = 0.005; compared with the non-MAFLD group) and MAFLD-diabetes (OR/CI: 1.5/1.1-2.1, P = 0.008; compared with the non-MAFLD group). MAFLD did not aggravate liver disease severity in patients with viral hepatitis. However, among NBNC subjects, factors associated with advanced liver disease included MAFLD-lean MS group (OR/CI: 9.1/2.4-34.6, P = 0.001; compared with non-MAFLD group) and MAFLD-DM group (OR/CI: 2.0/1.2-3.2, P = 0.004; compared with non-MAFLD group).

CONCLUSIONS

MAFLD patients with diabetes and metabolic dysregulation had a higher risk of advanced liver disease. The effect was more significant in non-viral hepatitis subjects in a community level.

The application of a novel platform of multiparametric magnetic resonance imaging in a bioenvironmental toxic carbon tetrachloride-induced mouse model of liver fibrosis

The use of multiparametric magnetic resonance imaging (MRI) to distinguish complex histopathological changes in liver fibrosis has not yet been systematically established. The purpose of this study is to gauge the efficacy of a cutting-edge MRI platform for evaluating ecotoxicologically hazardous carbon tetrachloride (CCl4) induced liver fibrosis, while also scrutinizing the relationship between MRI and its histopathological features. Thirty-six mice were randomly divided into 6 groups, each with 6 mice. Control mice received an intraperitoneal injection of olive oil, while the experimental mice received different doses of intraperitoneal injection of CCl4. Both sets underwent this process twice per week over a duration of 5 weeks. MRI measurements encompassed T1WI, T2WI, T1 mapping, T2 mapping, T2* mapping. Liver fibrosis and inflammation were assessed and classified using Metavir and activity scoring systems. CCl4 successfully induced liver fibrosis in mice, showing an increasing extent of liver fibrosis and liver function damage with the increasing dosage of CCl4. Compared with the control group, T1, ΔT1, and T2 in the experimental group were considerably elevated (P < 0.05) than those in the control group. Spearman's correlation showed that the correlation of Native T1 and △T1 with fibrosis (r = 0.712, 0.678) was better than with inflammation (r = 0.688, 0.536). T2 correlation with inflammation (r = 0.803) was superior to fibrosis (r = 0.568). ROC analysis showed that the AUC of Native T1 was highest (0.906), followed by ΔT1 (0.852), while the AUC increased to 0.945 when all relevant MRI parameters were combined. T1 is the most potent MRI parameter for evaluating CCl4-induced liver fibrosis, followed by ΔT1. Meanwhile, T2 may not be suitable for evaluating liver fibrosis but is more suitable for evaluating liver inflammation.

Inhibition of Dickkopf-1 enhances the anti-tumor efficacy of sorafenib via inhibition of the PI3K/Akt and Wnt/β-catenin pathways in hepatocellular carcinoma

BACKGROUND

Sorafenib improves the overall survival in patients with advanced hepatocellular carcinoma (HCC). Dickkopf-1 (DKK1) is commonly overexpressed in HCC. In this study, we investigated whether the inhibition of DKK1 enhances the anti-tumor efficacy of sorafenib in HCC.

METHODS

HCC cells were treated with sorafenib and WAY-262611, which is an inhibitor of DKK1. Transgenic mouse models were also developed using hydrodynamic tail vein injection. Mice were orally administered with sorafenib (32 mg/kg), WAY-262611 (16 mg/kg), or sorafenib + WAY-262611 for 10 days. Mechanisms of sorafenib and WAY-262611 were explored via western blotting, immunostaining, and RNA sequencing.

RESULTS

DKK1 was significantly overexpressed in patients with HCC than in the healthy controls and patients with liver diseases except HCC (all P < 0.05). Compared with sorafenib alone, sorafenib + WAY-262611 significantly inhibited the cell viability, invasion, migration, and colony formation by promoting apoptosis and altering the cell cycles in HCC cells (all P < 0.05). Moreover, sorafenib + WAY-262611 decreased the p110α, phospho-Akt (all P < 0.05), active β-catenin (all P < 0.05) and phospho-GSK-3β (Ser9) expression levels, while increasing the phospho-GSK-3β (Tyr216) expression levels compared with those in the sorafenib alone in vitro and in vivo. In addition, sorafenib + WAY-262611 inhibited tumor progression by regulating cell proliferation and apoptosis, significantly better than sorafenib alone in mouse models.

CONCLUSIONS

Our results indicate that DKK1 inhibition significantly enhances the anti-tumor efficacy of sorafenib by inhibiting the PI3K/Akt and Wnt/β-catenin pathways via regulation of GSK3β activity, suggesting a novel therapeutic strategy for HCC. Video Abstract.

Comparison between Two-Dimensional and Point Shear Wave Elastography Techniques in Evaluating Liver Fibrosis Using Histological Staging as the Reference Standard: A Prospective Pilot Study

Evaluation of hepatic fibrosis is essential to prevent liver-related morbidity and mortality. Although various types of ultrasound shear wave elastography (SWE) have been used and validated, there are limited studies on the relatively newer technique, two-dimensional SWE (2D-SWE). Therefore, this study aimed to compare the diagnostic performances of 2D-SWE and point SWE (p-SWE) for evaluating liver fibrosis using histology as the reference standard. To measure liver stiffness (LS) values, 87 patients underwent 2D-SWE and p-SWE using the same machine. Technical failures and unreliable measurements were also evaluated. The diagnostic performances of 2D-SWE and p-SWE were compared using area under the receiver operating characteristic (AUROC) curve analysis. No technical failures were observed in either method; however, unreliable measurements were less frequent in 2D-SWE (1/87 [1.1%]) than in p-SWE (8/87 [9.2%]) (p < 0.001). The AUROC of the LS values of 2D-SWE were significantly higher than those of p-SWE for diagnosing significant fibrosis (0.965 vs. 0.872, p = 0.022) and cirrhosis (0.994 vs. 0.886, p = 0.042). In conclusion, 2D-SWE is more reliable and accurate than p-SWE for diagnosing hepatic fibrosis.