Fibrosis-4 (FIB-4) score and D-dimer (DD) have emerged as prognostic markers in coronavirus disease 2019 (COVID-19). However, precise cutoff points remain undefined, and their combined use has been scarcely studied. We aimed to analyze FIB-4 and DD performance, individually and combined, to predict outcomes among COVID-19 patients.

From March to December 2020, hospitalized COVID-19 patients were evaluated based on clinical and laboratory tests from their first day of hospitalization. Primary outcome was inhospital mortality, and secondary outcomes included hospital stay length, ICU admission and duration, need for hemodialysis, ventilatory support, and extent of lung involvement. Optimal FIB-4 and DD cutoff points to predict mortality were established to maximize sensitivity and specificity. A sequential diagnostic strategy using both markers was subsequently evaluated.

Among 518 patients (61 ± 16 years, 64% men), the inhospital mortality rate was 18%. FIB-4 outperformed DD in predicting mortality (area under the receiver operating characteristic curve: 0.76 vs. 0.65, P = 0.003) and was chosen as the first step in sequential analysis. Mortality was higher in patients with FIB-4 ≥1.76 vs. FIB-4 <1.76 (26 vs. 5%, P < 0.001) and DD ≥2000 ng/ml vs. DD <2000 ng/ml (38 vs. 16%, P < 0.001). Using FIB-4 as a screening test (cutoff = 1.76, 90% sensitivity) followed by DD (cutoff = 2000 ng/ml; 90% specificity) identified a subgroup with higher mortality when compared with FIB-4 alone (48 vs. 26%, P < 0.001), missing the identification of only 2% of deaths.

Sequential use of FIB-4 and DD represents a comprehensive strategy to identify high-risk COVID-19 patients at hospital admission, potentially minimizing unnecessary DD tests in those deemed low-risk by FIB-4.

In managing metabolic dysfunction-associated steatotic liver disease, which affects over 30% of the general population, effective noninvasive biomarkers for assessing disease severity, monitoring disease progression, predicting the development of liver-related complications, and assessing treatment response are crucial. The advantage of simple fibrosis scores lies in their widespread accessibility through routinely performed blood tests and extensive validation in different clinical settings. They have shown reasonable accuracy in diagnosing advanced fibrosis and good performance in excluding the majority of patients with a low risk of liver-related complications. Among patients with elevated serum fibrosis scores, a more specific fibrosis and imaging biomarker has proved useful to accurately identify patients at risk of liver-related complications. Among specific fibrosis blood biomarkers, enhanced liver fibrosis is the most widely utilized and has been approved in the United States as a prognostic biomarker. For imaging biomarkers, the availability of vibration-controlled transient elastography has been largely improved over the past years, enabling the use of liver stiffness measurement (LSM) for accurate assessment of significant and advanced fibrosis, and cirrhosis. Combining LSM with other routinely available blood tests enhances the ability to diagnose at-risk metabolic dysfunction-associated steatohepatitis and predict liver-related complications, some reaching an accuracy comparable to that of liver biopsy. Magnetic resonance imaging-based modalities provide the most accurate quantification of liver fibrosis, though the current utilization is limited to research settings. Expanding their future use in clinical practice depends on factors such as cost and facility availability.

Accurate and reliable diagnosis and monitoring of hepatic fibrosis is increasingly important given the variable natural history in chronic liver disease (CLD) and expanding antifibrotic therapeutic options targeting reversibility of early-stage cirrhosis. This highlights the need to develop more refined and effective noninvasive techniques for the dynamic assessment of fibrogenesis and fibrolysis.

We conducted a literature review on PubMed, from 1 December 1970, to 1 November 2024, to evaluate and compare available blood-based and imaging-based noninvasive tools for hepatic fibrosis diagnosis and monitoring. Simple scores such as FIB-4 and NAFLD fibrosis score are suitable for excluding significant or advanced fibrosis, while tertiary centers should adopt complex scores and liver stiffness measurement as part of a secondary diagnostic and more comprehensive evaluation. Moreover, the advent of multiomics for high-resolution molecular profiling, and integration of artificial intelligence for noninvasive diagnostics holds promise for revolutionizing fibrosis monitoring and treatment through novel biomarker discovery and predictive omics-based algorithms.

The increased shift toward noninvasive diagnostics for liver fibrosis needs to align with personalized medicine, enabling more effective, tailored management strategies for patients with liver disease in the future.

In patients with metabolic dysfunction-associated steatotic liver disease (MASLD), there are limited data on how changes in FIB4 and liver stiffness measurement (LSM) correlate in non-biopsy cohorts.

Our objective was to evaluate associations between changes in FIB4 and LSM in MASLD patients.

We included MASLD patients with serial VCTE from 2015-2022. The primary predictors were change in FIB4 and presence of diabetes, obesity, and high alanine aminotransferase (ALT). The primary outcome, applied only to patients with LSM1 < 8 kPa, was incident significant fibrosis (SF) defined as a ≥ 20% increase in LSM2 vs. LSM1 and LSM2 ≥ 8 kPa. A secondary outcome was LSM progression with a similar definition but applied to all participants, not only those with LSM1 < 8 kPa.

Of 285 included patients, 216 had LSM1 < 8 kPa and were included in the primary analysis; of these, 34 (16%) had incident SF. Changes in FIB4 correlated with changes in LSM (R = 0.16, p = 0.016). Independent predictors of incident SF included comorbid diabetes mellitus (OR 2.43, 95% CI 1.04-6.56), obesity (OR 3.88, 95% CI 1.63-9.25), and baseline ALT ≥ 30 (OR 8.55, 95% CI 1.10-66.29). A model including ALT, diabetes, and obesity outperformed a model with FIB4 change alone.

Among patients with MASLD, changes in FIB4 correlated with changes in LSM but more significant correlates of incident significant fibrosis included diabetes mellitus, obesity, and high baseline ALT.

We investigated the effects of testosterone replacement therapy (TRT) on the Fibrosis-4 (FIB-4) index among hypogonadal patients who were extracted from a randomized controlled study in Japan (the EARTH study).

Data of 186 patients (88 in the TRT group; 98 in the control group) were collected. The patients in the TRT group received intramuscular administration of testosterone enanthate (250 mg) every 4 weeks for 12 months. The patients' background information such as current medical history and lifestyle habits were collected. Waist circumference, body mass index, and body fat volume were measured at baseline and 12-month visit. Fasting blood sugar (FBS), hemoglobin A1c, total cholesterol, triglyceride (TG), and high-density lipoprotein cholesterol levels were collected at baseline and 12-month visit. The FIB-4 index was calculated according to age, aspartate aminotransferase, alanine transaminase, and platelet count.

Except for serum FBS values, most of baseline characteristics were comparable between the TRT and control groups. When comparing the changes of each variable from baseline at 12-month visit in both groups, significant differences were found in waist circumference (p=0.00248), fat volume (p=0.00812), and platelet counts (p=0.0478), whereas a FIB-4 index did not change. On the contrary, in a subanalysis including only patients with a FIB-4 index ≥1.30 at baseline, a significant difference in a FIB-4 index (-0.10±0.39 vs. 0.04±0.44; p=0.0311) was observed with significant decreases in waist circumference, body fat volume, and TG levels, and an increase in platelet counts. The FIB-4 index was significantly decreased by TRT from 1.98±0.52 to 1.87±0.60 (p=0.0277).

TRT for 12 months improved the FIB-4 index among hypogonadal men with a higher baseline FIB-4 index.

Non-alcoholic fatty liver disease (NAFLD), one of the most common chronic liver diseases with a prevalence of 23%-25% globally, is an independent risk factor for cardiovascular diseases (CVDs). Growing evidence indicates that the development of NAFLD, ranging from non-alcoholic fatty liver (NAFL), non-alcoholic steatohepatitis (NASH), advanced fibrosis to cirrhosis, and even hepatocellular carcinoma, is at substantial risk for CVDs, which clinically contribute to increased cardiovascular morbidity and mortality. Non-invasive serum markers assessing liver fibrosis, such as fibrosis-4 (FIB-4) score, aspartate transaminase-to-platelet ratio index (APRI), and NAFLD fibrosis score (NFS), are expected to be useful tools for clinical management of patients with CVDs. This review aims to provide an overview of the evidence for the relationship between the progression of NAFLD and CVDs and the clinical application of non-invasive markers of liver fibrosis in managing patients with CVDs.

Liver biopsy is still the gold standard in the staging of nonalcoholic fatty liver disease (NAFLD), which is the most common chronic liver disease worldwide. However, being an invasive method, liver biopsy has limited use in clinical practice. The aim of this study was to determine the relationship between serum levels of cytokeratin 18 (CK-M30) and N-terminal procollagen III propeptide (PIIINP) in patients with biopsy-proven NAFLD. The study was carried out on volunteers, including both healthy individuals and patients pre-diagnosed with NAFLD. The liver biopsies were re-assessed by applying the Steatosis, Activity, Fibrosis/Fatty Liver Inhibition of Progression (SAF/FLIP) algorithm. At the end of the study, frozen serum samples (-80 °C) were analyzed using commercial kits. CK18-M30 and PIIINP levels significantly differed in all study groups. There was no significant correlation between serum levels of CK18-M30 and PIIINP in healthy individuals but there was a significant positive correlation between CK18-M30 and PIIINP levels in NAFLD (NAFL-nonalcoholic steatohepatitis (NASH)) groups. CK18-M30 was better than PIIINP at distinguishing between NAFL and NASH. The results obtained for biopsy-proven NAFLD demonstrated that both PIIINP and CK18-M30 were partly associated with histological parameters and could aid in distinguishing between NASH and NAFL.

The value of non-invasive tests for monitoring the resolution of significant liver fibrosis after treatment is poorly investigated. We compared the performances of six non-invasive tests to predict the resolution of significant fibrosis after bariatric surgery.

Participants were individuals with obesity submitted to needle liver biopsy at the time of bariatric surgery, and 12 and/or 60 months after surgery. We calculated the fibrosis-4 index (FIB-4), NAFLD fibrosis score (NFS), AST to platelet ratio index (APRI), Hepatic fibrosis score (HFS), Fibrotic NASH index (FNI), and Liver risk score (LRS) at each time point, and compared their performances for predicting significant fibrosis (F ≥ 2) and its resolution following surgery.

At baseline, 2436 patients had liver biopsy, including 261 (10.7 %) with significant fibrosis. Overall, 672 patients had pre- and post-operative biopsies (564 at M12 and 328 at M60). The fibrosis stage decreased at M12 and M60 (p < 0.001 vs M0). Resolution of significant fibrosis occurred in 58/121 (47.9 %) at M12 and 32/50 (64 %) at M60. The mean value of all tests decreased after surgery, except for FIB-4. Performances for predicting fibrosis resolution was higher at M60 than at M12 for all tests, and maximal at M60 for FNI and LRS: area under the curve 0.843 (95%CI 0.71-0.95) and 0.92 (95%CI 0.84-1.00); positive likelihood ratio 3.75 (95 % CI 1.33-10.59) and 4.58 (95 % CI 1.65-12.70), respectively.

Results showed the value and limits of non-invasive tests for monitoring the evolution of liver fibrosis after an intervention. Following bariatric surgery, the best performances to predict the resolution of significant fibrosis were observed at M60 with tests combining liver and metabolic traits, namely FNI and LRS.

The long-term results of web-based behavioural intervention in non-alcoholic fatty liver disease (NAFLD) have not been described in patients followed in specialised centres.

To analyse the long-term effectiveness of web education compared with the results achieved by a group-based behavioural intervention in the same years 2012-2014.

We followed 679 patients with NAFLD (web-based, n = 290; group-based, n = 389) for 5 years. Weight loss ≥10% was the primary outcome; secondary outcomes were attrition, changes in liver enzymes and in biomarkers of steatosis (Fatty liver Index) and fibrosis (Fibrosis-4 index).

The cohorts differed in age, education, working status and presence of diabetes. Attrition was higher in the web-based cohort (hazard ratio: 1.53; 95% CI: 1.24-1.88), but not different after adjustment for confounders. Among patients in active follow-up, 50% lost ≥5% of initial body weight and 19% lost ≥10%, without difference between cohorts. Alanine aminotransferase levels fell to within the normal range in 51% and 45% of web- and group-based cohorts, respectively. Fatty Liver Index declined progressively and, by year 5, it ruled out steatosis in 4.8%, whereas 24.9% were in the indeterminate range. Fibrosis-4 index increased in both cohorts, driven by age, but the prevalence of cases ruling-in advanced fibrosis remained very low (around 1%). Improvements in the class of both surrogate biomarkers were associated with ≥5% weight loss.

Although burdened by attrition, web-based behavioural intervention is feasible and effective in NAFLD, expanding the cohort involved in behavioural programs and reducing the risk of progressive disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as Nonalcoholic fatty liver disease (NAFLD), is one of the most common hepatic diseases in individuals with overweight or obesity. In this context, a panel of experts from three medical societies was organized to develop an evidence-based guideline on the screening, diagnosis, treatment, and follow-up of MASLD.

A MEDLINE search was performed to identify randomized clinical trials, meta-analyses, cohort studies, observational studies, and other relevant studies on NAFLD. In the absence of studies on a certain topic or when the quality of the study was not adequate, the opinion of experts was adopted. Classes of Recommendation and Levels of Evidence were determined using prespecified criteria.

Based on the literature review, 48 specific recommendations were elaborated, including 11 on screening and diagnosis, 9 on follow-up,14 on nonpharmacologic treatment, and 14 on pharmacologic and surgical treatment.

A literature search allowed the development of evidence-based guidelines on the screening, diagnosis, treatment, and follow-up of MASLD in individuals with overweight or obesity.

There are no approved diagnostic biomarkers for at-risk non-alcoholic steatohepatitis (NASH), defined by the presence of NASH, high histological activity and fibrosis stage ≥2, which is associated with higher incidence of liver-related events and mortality. FNIH-NIMBLE is a multi-stakeholder project to support regulatory approval of NASH-related biomarkers. The diagnostic performance of five blood-based panels was evaluated in an observational (NASH CRN DB2) cohort (n = 1,073) with full spectrum of non-alcoholic fatty liver disease (NAFLD). The panels were intended to diagnose at-risk NASH (NIS4), presence of NASH (OWLiver) or fibrosis stages >2, >3 or 4 (enhanced liver fibrosis (ELF) test, PROC3 and FibroMeter VCTE). The prespecified performance metric was an area under the receiver operating characteristic curve (AUROC) ≥0.7 and superiority over alanine aminotransferase for disease activity and the FIB-4 test for fibrosis severity. Multiple biomarkers met these metrics. NIS4 had an AUROC of 0.81 (95% confidence interval: 0.78-0.84) for at-risk NASH. The AUROCs of the ELF test, PROC3 and FibroMeterVCTE for clinically significant fibrosis (≥stage 2), advanced fibrosis (≥stage 3) or cirrhosis (stage 4), respectively, were all ≥0.8. ELF and FibroMeter VCTE outperformed FIB-4 for all fibrosis endpoints. These data represent a milestone toward qualification of several biomarker panels for at-risk NASH and also fibrosis severity in individuals with NAFLD.

Genetic variants affecting liver disease risk vary among racial and ethnic groups. Hispanics/Latinos in the United States have a high prevalence of PNPLA3 I148M, which increases liver disease risk, and a low prevalence of HSD17B13 predicted loss-of-function (pLoF) variants, which reduce risk. Less is known about the prevalence of liver disease-associated variants among Hispanic/Latino subpopulations defined by country of origin and genetic ancestry. We evaluated the prevalence of HSD17B13 pLoF variants and PNPLA3 I148M, and their associations with quantitative liver phenotypes in Hispanic/Latino participants from an electronic health record-linked biobank in New York City.

This study included 8739 adult Hispanic/Latino participants of the BioMe biobank with genotyping and exome sequencing data. We estimated the prevalence of Hispanic/Latino individuals harboring HSD17B13 and PNPLA3 variants, stratified by genetic ancestry, and performed association analyses between variants and liver enzymes and Fibrosis-4 (FIB-4) scores.

Individuals with ancestry from Ecuador and Mexico had the lowest frequency of HSD17B13 pLoF variants (10%/7%) and the highest frequency of PNPLA3 I148M (54%/65%). These ancestry groups had the highest outpatient alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and the largest proportion of individuals with a FIB-4 score greater than 2.67. HSD17B13 pLoF variants were associated with reduced ALT level (P = .002), AST level (P < .001), and FIB-4 score (P = .045). PNPLA3 I148M was associated with increased ALT level, AST level, and FIB-4 score (P < .001 for all). HSD17B13 pLoF variants mitigated the increase in ALT conferred by PNPLA3 I148M (P = .006).

Variation in HSD17B13 and PNPLA3 variants across genetic ancestry groups may contribute to differential risk for liver fibrosis among Hispanic/Latino individuals.

Nonalcoholic fatty liver disease (NAFLD) has emerged as a leading cause of liver-related morbidity and mortality worldwide, afflicting approximately a billion individuals. NAFLD is a slowly progressive disease that may evolve in a subset of patients toward cirrhosis, hepatocellular carcinoma, and end-stage liver disease. Liver fibrosis severity is the strongest predictor of clinical outcomes. The emergence of effective therapeutics on the horizon highlights the need to identify among patients with NAFLD, those with severe fibrosis or cirrhosis, who are the most at risk of developing complications and target them for therapy. Liver biopsy has been the reference standard for this purpose. However, it is not suitable for large-scale population evaluation, given its well-known limitations (invasiveness, rare but severe complications, and sampling variability). Thus, there have been major efforts to develop simple noninvasive tools that can be used in routine clinical settings and in drug development. Noninvasive approaches are based on the quantification of biomarkers in serum samples or on the measurement of liver stiffness, using either ultrasound- or magnetic resonance-based elastography techniques. This review provides a roadmap for future development and integration of noninvasive tools in clinical practice and in drug development in NAFLD. We discuss herein the principles for their development and validation, their use in clinical practice, including for diagnosis of NAFLD, risk stratification in primary care and hepatology settings, prediction of long-term liver-related and non-liver-related outcomes, monitoring of fibrosis progression and regression, and response to future treatment.

Peroxisome proliferator-activated receptor (PPAR) agonists may have favorable outcomes on non-alcoholic fatty liver disease. This study serves as proof of concept to evaluate whether dual PPAR-α/γ agonists improve non-invasive tests of liver steatosis and fibrosis.

This is a post-hoc analysis of a randomized, double-blind, placebo-controlled, multi-center trial comprising 7226 patients with type 2 diabetes mellitus and recent coronary artery disease randomized to receive aleglitazar, a PPAR-α/γ agonists, or placebo for two years. Main outcomes were change in non-invasive tests for liver steatosis and fibrosis: Liver Fat Score (LFS), Liver Accumulation Product (LAP), Fibrosis-4 (FIB-4), and NAFLD Fibrosis Score (NFS).

LFS, LAP and FIB-4 decreased upon treatment, whereas scores in the placebo group remained the same or increased (P<0.001). NFS responded differently but remained consistently lower than placebo. In the treatment group more participants shifted to a lower FIB-4 and NFS category, or improved in respect to the LAP cut-off values compared to the placebo group (P<0.001 for FIB-4 and LAP, P<0.004 for NFS). LFS had a low discriminative power in this study.

This post-hoc analysis showed improvement of non-invasive tests of liver steatosis and fibrosis after starting dual PPAR-α/γ agonist treatment, adding to the evidence that this pathway has potential in non-alcoholic fatty liver disease treatment.

Nonalcoholic fatty liver disease (NAFLD), including advanced-stage nonalcoholic steatohepatitis (NASH), is currently the most common chronic liver disease worldwide and is projected to become the leading indication for liver transplantation (LT). However, there are no effective pharmacological therapies for NAFLD. Endoscopic bariatric and metabolic therapies (EBMTs) are less invasive procedures for the treatment of obesity and its metabolic comorbidities. Several recent studies have demonstrated the beneficial effects of EBMTs on NAFLD/NASH. In this review, we summarize the major EBMTs and their mechanisms of action. We further discuss the current evidence on the efficacy and safety of EBMTs in people with NAFLD/NASH and obese cirrhotic LT candidates. The potential utility of EBMTs in reducing liver volume and perioperative complications in bariatric surgery candidates is also discussed. Moreover, we review the development of liver abscesses as a common serious adverse event in duodenal-jejunal bypass liner implantation.

Whereas diagnostic tests help detect the cause of signs and symptoms, prognostic tests assist in evaluating the probable course of the disease and future outcome. Studies to evaluate prognostic tests are longitudinal, which introduces sources of bias different from those for diagnostic accuracy studies. At present, systematic reviews of prognostic tests often use the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2) tool to assess risk of bias and applicability of included studies because no equivalent instrument exists for prognostic accuracy studies. QUAPAS (Quality Assessment of Prognostic Accuracy Studies) is an adaptation of QUADAS-2 for prognostic accuracy studies. Questions likely to identify bias were evaluated in parallel and collated from QUIPS (Quality in Prognosis Studies) and PROBAST (Prediction Model Risk of Bias Assessment Tool) and paired to the corresponding question (or domain) in QUADAS-2. A steering group conducted and reviewed 3 rounds of modifications before arriving at the final set of domains and signaling questions. QUAPAS follows the same steps as QUADAS-2: Specify the review question, tailor the tool, draw a flow diagram, judge risk of bias, and identify applicability concerns. Risk of bias is judged across the following 5 domains: participants, index test, outcome, flow and timing, and analysis. Signaling questions assist the final judgment for each domain. Applicability concerns are assessed for the first 4 domains. The authors used QUAPAS in parallel with QUADAS-2 and QUIPS in a systematic review of prognostic accuracy studies. QUAPAS improved the assessment of the flow and timing domain and flagged a study at risk of bias in the new analysis domain. Judgment of risk of bias in the analysis domain was challenging because of sparse reporting of statistical methods.

Non-alcoholic steatohepatitis (NASH) is a chronic, progressive fibrotic liver disease that can lead to cirrhosis. While liver biopsy is considered the reference standard for the histologic diagnosis of NASH and staging of fibrosis, its use in clinical practice is limited. Non-invasive tests (NITs) are increasingly being used to identify and stage liver fibrosis in patients with NASH, and several can assess liver-related outcomes. We report changes in various NITs in patients treated with obeticholic acid (OCA) or placebo in the phase III REGENERATE study.

Patients with NASH and fibrosis stage F2 or F3 (n = 931) were randomized (1:1:1) to receive placebo, OCA 10 mg, or OCA 25 mg once daily. Various NITs based on clinical chemistry and/or imaging were evaluated at baseline and throughout the study.

Rapid, sustained reductions from baseline in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase levels, as well as in Fibrosis-4 (FIB-4), FibroTest, FibroMeter, and FibroScan-AST scores were observed in OCA-treated vs. placebo-treated patients. Reduction in liver stiffness by vibration-controlled transient elastography was observed in the OCA 25 mg group vs. the placebo group at Month 18. NIT changes were associated with shifts in histologic fibrosis stage. The greatest improvements were observed in patients with ≥1-stage fibrosis improvement; however, improvements in ALT, AST, FIB-4, and FibroTest were also observed in OCA-treated patients whose histologic fibrosis remained stable.

Based on the REGENERATE Month 18 interim analysis, rapid and sustained improvements in various NITs were observed with OCA treatment. Dynamic changes in selected NITs separated histologic responders from non-responders. These results suggest that NITs may be useful in assessing histologic response to OCA therapy. CLINICALTRIALS.

NCT02548351 LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is a chronic, progressive liver disease that can lead to cirrhosis. To diagnose and assess liver fibrosis (scarring) in patients with NASH, non-invasive tests (NITs) are increasingly being used rather than liver biopsy, which is invasive, expensive, and can be risky. In the REGENERATE study, which is evaluating the effects of obeticholic acid vs. placebo in patients with NASH, various NITs were also evaluated. This analysis shows that improvements in levels of certain blood components, as well as favorable results of ultrasound imaging and proprietary tests of liver function, were associated with improvements in liver fibrosis after treatment with obeticholic acid, suggesting that NITs may be useful alternatives to liver biopsy in assessing NASH patients' response to therapy.

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.

Nonalcoholic fatty liver disease [NAFLD] is a condition affecting a vast portion of the worldwide population. The presence of underlying fibrosis is the strongest predictor of long-term outcomes and mortality, with a graduated increase in liver-related morbidity and mortality with progression from moderate fibrosis tobiomarkers targeting collagen turnover and extracellular matrix remodeling FibroTest FAST™, Velacur™, MRE]. While many of these provide a robust, stand alone value, the accuracy of these noninvasive tests markedly increase when used in combination or in sequential order with one another. There is not a uniform consensus demonstrating superiority of any specific test. Given the growing role and accuracy of these tests, they should have an expanding role in the assessment of fibrosis across this patient population and obviate the need for liver biopsy in a large portion of patients. Future clinical studies should focus on validating these novel biomarkers, as well as optimizing the sequential or algorithmic testing when combining these noninvasive tests.

Nonalcoholic steatohepatitis (NASH), a chronic liver disease without an approved therapy, is associated with lipotoxicity and insulin resistance and is a major cause of cirrhosis and hepatocellular carcinoma. Aramchol, a partial inhibitor of hepatic stearoyl-CoA desaturase (SCD1) improved steatohepatitis and fibrosis in rodents and reduced steatosis in an early clinical trial. ARREST, a 52-week, double-blind, placebo-controlled, phase 2b trial randomized 247 patients with NASH (n = 101, n = 98 and n = 48 in the Aramchol 400 mg, 600 mg and placebo arms, respectively; NCT02279524 ). The primary end point was a decrease in hepatic triglycerides by magnetic resonance spectroscopy at 52 weeks with a dose of 600 mg of Aramchol. Key secondary end points included liver histology and alanine aminotransferase (ALT). Aramchol 600 mg produced a placebo-corrected decrease in liver triglycerides without meeting the prespecified significance (-3.1, 95% confidence interval (CI) -6.4 to 0.2, P = 0.066), precluding further formal statistical analysis. NASH resolution without worsening fibrosis was achieved in 16.7% (13 out of 78) of Aramchol 600 mg versus 5% (2 out of 40) of the placebo arm (odds ratio (OR) = 4.74, 95% CI = 0.99 to 22.7) and fibrosis improvement by ≥1 stage without worsening NASH in 29.5% versus 17.5% (OR = 1.88, 95% CI = 0.7 to 5.0), respectively. The placebo-corrected decrease in ALT for 600 mg was -29.1 IU l-1 (95% CI = -41.6 to -16.5). Early termination due to adverse events (AEs) was <5%, and Aramchol 600 and 400 mg were safe, well tolerated and without imbalance in serious or severe AEs between arms. Although the primary end point of a reduction in liver fat did not meet the prespecified significance level with Aramchol 600 mg, the observed safety and changes in liver histology and enzymes provide a rationale for SCD1 modulation as a promising therapy for NASH and fibrosis and are being evaluated in an ongoing phase 3 program.

Effective therapy for clinically significant fibrosis in nonalcoholic fatty liver disease (NAFLD) is an unmet need. Data on the effectiveness of endoscopic placement of intragastric balloon (IGB) in patients with NAFLD are limited. In this study, we evaluated the impact of IGB placement in NAFLD patients with advanced fibrosis.

We retrospectively assessed the effects of the Orbera™ fluid-filled IGB in a cohort of obese patients with liver stiffness ≥9.7 kPa (corresponding to F3-F4). Patients with endoscopic signs of portal hypertension were excluded. Changes in metabolic and liver parameters from baseline to follow-up (6 mo) were assessed.

A total of 26 obese patients, aged 53 [44 - 62] years, with BMI 35.1 ± 4.7 kg/m² were included. All patients achieved a significant body weight loss (106 ± 19.7 vs. 92 ± 18.3 kg, P < .001) and waist circumference reduction (116 ± 13.3 vs. 104 ± 13.4 kg, P < .001) at 6-month follow-up after IGB placement. Weight loss induced by IGB lowered blood glucose (140 [112; 169] vs. 118 [94; 144] mg/dl, P < .01), glycated hemoglobin (7.5 ± 1.3 vs. 6.6 ± 1.2%, P < .001), FIB-4 (3.2 ± 0.7 vs. 2.7 ± 0.8, P < .001), liver stiffness (13.3 ± 3.2 vs. 11.3 ± 2.8 kPa, P < .001) and controlled attenuation parameter (355 [298-400] vs. 296 [255-352] dB/m, P < .01). Gastroesophageal reflux symptoms were common, but no severe adverse event was observed.

Obese patients with advanced liver fibrosis, treated with 6-month IGB, can achieve regression of fibrosis as assessed by reduction of liver stiffness and FIB-4. Randomized controlled trials are needed to confirm these findings.

This review evaluates the ability of the fibrosis index based on four factors (FIB-4) identifying fibrosis stages, long-time prognosis in chronic liver disease, and short-time outcomes in acute liver injury. FIB-4 was accurate in predicting the absence or presence of advanced fibrosis with cut-offs of 1.0 and 2.65 for viral hepatitis B, 1.45 and 3.25 for viral hepatitis C, 1.30 (<65 years), 2.0 (≥65 years), and 2.67 for non-alcoholic fatty liver disease (NAFLD), respectively, but had a low-to-moderate accuracy in alcoholic liver disease (ALD) and autoimmune hepatitis. It performed better in excluding fibrosis, so we built an algorithm for identifying advanced fibrosis by combined methods and giving work-up and follow-up suggestions. High FIB-4 in viral hepatitis, NAFLD, and ALD was associated with significantly high hepatocellular carcinoma incidence and mortality. Additionally, FIB-4 showed the ability to predict high-risk varices with cut-offs of 2.87 and 3.91 in cirrhosis patients and predict long-term survival in hepatocellular carcinoma patients after hepatectomy. In acute liver injury caused by COVID-19, FIB-4 had a predictive value for mechanical ventilation and 30-day mortality. Finally, FIB-4 may act as a screening tool in the secondary prevention of NAFLD in the high-risk population.

This study aimed to analyze the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on the indexes of liver fibrosis in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease, and also to observe the effects on liver enzymes and liver fat.

This meta-analysis was performed using RevMan 5.3 statistical software.

SGLT2 inhibitors could significantly reduce the level of hepatic fibrosis index: fibrosis-4 (mean difference [MD] 0.25, 95% CI -0.39 to -0.11, p = 0.0007); serum type Ⅳ collagen 7s (MD 0.32, 95% CI -0.59 to -0.04, p = 0.02); and ferritin (MD 26.7, 95% CI 50.64, 2.76, p = 0.03). SGLT2 inhibitors could significantly reduce the level of liver enzymes: alanine aminotransferase (MD 3.49, 95% CI -5.1 to 1.58, p < 0.0001); aspartate aminotransferase (MD 3.64, 95% CI -5.10 to -2.18, p < 0.00001); and glutamate aminotransferase (MD 7.13, 95% CI -12.95 to -1.32, p = 0.02). SGLT2 inhibitors could significantly reduce the level of liver fat: liver-to-spleen attenuation ratio (MD 0.16, 95% CI 0.10-0.22, p < 0.00001); magnetic resonance imaging proton density fat fraction (MD 1.97, 95% CI -3.49 to -0.45, p = 0.01); liver controlled attenuation parameter (MD 0.29, 95% CI -26.95 to -13.64, p < 0.00001); liver fat score (MD 0.55, 95% CI 1.04 to -0.05, p = 0.03); and liver fat index (MD 11.21, 95% CI -16.53 to -5.89, p < 0.0001).

SGLT2 inhibitors could improve liver fibrosis, liver enzymes, liver fat, and metabolic indexes in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease.

Currently, there is no pharmacotherapy for non-alcoholic steatohepatitis (NASH), a common liver disorder. In contrast, primary biliary cholangitis (PBC) is a chronic cholestatic liver disease for which ursodeoxycholic acid (UDCA) is the drug of choice. However, 50% of PBC patients may not respond to UDCA. Obeticholic acid (OCA) is emerging as a vital pharmacotherapy for these chronic disorders. We aimed to analyse the safety and efficacy of OCA.

We performed an extensive search of electronic databases from 01/01/2000 to 31/03/2020. We included randomized controlled trials of OCA in patients with NASH, PBC, and primary sclerosing cholangitis (PSC). We assessed the histological improvement in NASH, reduction in alkaline phosphatase (≤1.67 ULN) in PBC, and the adverse effects of OCA.

Seven RCTs (n = 2834) were included. Of the total RCTs, there were three on both NASH and PBC and one on PSC. OCA improved NASH fibrosis [OR: 1.95 (1.47-2.59; p < 0.001)]. With the 10 mg OCA dose, the odds of improvement was 1.61 (1.03-2.51; p = 0.03), while with the 25 mg dose, it was 2.23 (1.55-3.18; p < 0.001). However, 25 mg OCA led to significant adverse events and discontinuation of the drug [2.8 (1.42-3.02); p < 0.001)] compared with 10 mg OCA [0.95 (0.6-1.5); p = 0.84] in NASH patients. In PBC patients, the response to 5 mg OCA was better than with the higher doses [5 mg: 7.66 (3.12-18.81; p < 0.001), 10 mg: 5.18 (2-13.41; p = 0.001), 25 mg: 2.36 (0.94-5.93; p = 0.06), 50 mg: 4.08 (1.05-15.78; p = 0.04)]. The risk of pruritus was lowest with 5 mg OCA.

Lower doses of OCA are effective and safe in NASH and cholestatic liver disease. While 10 mg OCA is effective for NASH fibrosis regression, only 5 mg OCA is required for PBC.

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.

Non-alcoholic fatty liver disease (NAFLD), often associated with obesity and metabolic syndrome, manifests itself as steatosis, hepatic fibrosis, cirrhosis, or even end-stage liver disease. NAFLD causes inflammation, insulin resistance and cardiovascular complications. The current study aimed to evaluate the beneficial effects of bariatric surgery on biochemical parameters of hepatic functions in obese patients by comparing them before and one-year after the surgery.

A total of 72 morbidly obese patients underwent bariatric surgery between 2016 and 2018. The incidence of diabetes mellitus in this group was 29%, median body weight was 124.5 kg (109.0-140.0) and mean body mass index (BMI) was 44.38 ± 6.770 kg/m². The used surgical procedures included gastric bypass, sleeve gastrectomy, laparoscopic gastric plication, and single anastomosis duodeno-ileal bypass-sleeve gastrectomy. Biochemical parameters including ALT/AST ratio (AAR), NAFLD fibrosis score (NFS), hepatic fibrosis index (FIB-4) and Fatty Liver Index (FLI) were evaluated in all patients at the time of surgery and one year after the intervention.

Significant improvement after the intervention was observed in 64 patients. A significant reduction in body weight (P<0.0001), waist circumference (P<0.0001), and body mass index (P<0.0001) were observed. NAFLD liver fibrosis index changed significantly (P<0.0001), suggesting a trend of improvement from advanced fibrosis towards stages 0-2. The FIB-4 fibrosis index indicated significant improvement (P=0.0136). Besides, a significant decline in hepatic steatosis (P<0.0001) was observed after bariatric surgery as compared to the pre-surgery fatty liver conditions.

Among the strategies to overcome NAFLD-associated impediments, bariatric surgery can be considered effective in reducing obesity and metabolic co-morbidities.

ClinicalTrials.gov (NCT04569396).

There is intense research for drugs able to reduce disease progression in nonalcoholic fatty liver disease. We aimed to test the impact of novel antidiabetic drugs (dipeptidyl-peptidase-4 inhibitors - DPP-4Is, glucagon-like peptide-1 receptor agonists - GLP-1RAs, sodium-glucose cotransporter-2 inhibitors - SGLT-2Is) on non-invasive biomarkers of steatosis (fatty liver index, FLI) and fibrosis (Fibrosis-4 score, FIB-4) in patients with type 2 diabetes (T2D).

Clinical, anthropometric and biochemical parameters were retrospectively analysed in 637 consecutive T2D patients switched from metformin w/wo sulfonylureas and/or pioglitazone to DPP-4Is, GLP-1RAs and SGLT-2Is in a tertiary care setting. 165 patients maintained on original treatments served as controls. The effects on FLI and FIB-4 at 6- and 12-month follow-up were analysed by logistic regression after adjustment for baseline differences, computed by propensity scores, and additional adjustment for changes in glycosylated hemoglobin (HbA1c) and body mass index.

Body mass index, HbA1c and aminotrasferases significantly decreased following switching to GLP-1RAs and SGLT2-Is, compared with both controls and DPP-4Is, whereas only HbA1c was reduced on DPP-4Is. FLI and FIB-4 were reduced on GLP-1RA and SGLT-2I; logistic regression analysis confirmed a significant improvement of both biomarkers after adjustment for propensity score. The shift of FIB-4 values towards the category ruling out advanced fibrosis was maintained after additional adjustment for confounders. These effects were confirmed in a sensitivity analysis on effect size.

Glucagon-like peptide-1 receptor agonists and SGLT-2Is improve biomarkers of steatosis and fibrosis, in keeping with beneficial effects on liver disease progression, and should be considered the treatment of choice in T2D.

The prevalence of obesity or metabolic syndrome is increasing worldwide (globally metabodemic). Approximately 25% of the adult general population is suffering from nonalcoholic fatty liver disease (NAFLD), which has become a serious health problem. In 2020, global experts suggested that the nomenclature of NAFLD should be updated to metabolic-dysfunction-associated fatty liver disease (MAFLD). Hepatic fibrosis is the most significant determinant of all cause- and liver -related mortality in MAFLD. The non-invasive test (NIT) is urgently required to evaluate hepatic fibrosis in MAFLD. The fibrosis-4 (FIB-4) index is the first triaging tool for excluding advanced fibrosis because of its accuracy, simplicity, and cheapness, especially for general physicians or endocrinologists, although the FIB-4 index has several drawbacks. Accumulating evidence has suggested that vibration-controlled transient elastography (VCTE) and the enhanced liver fibrosis (ELF) test may become useful as the second step after triaging by the FIB-4 index. The leading cause of mortality in MAFLD is cardiovascular disease (CVD), extrahepatic malignancy, and liver-related diseases. MAFLD often complicates chronic kidney disease (CKD), resulting in increased simultaneous liver kidney transplantation. The FIB-4 index could be a predictor of not only liver-related mortality and incident hepatocellular carcinoma, but also prevalent and incident CKD, CVD, and extrahepatic malignancy. Although NITs as milestones for evaluating treatment efficacy have never been established, the FIB-4 index is expected to reflect histological hepatic fibrosis after treatment in several longitudinal studies. We here review the role of the FIB-4 index in the management of MAFLD.

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and has the potential risk for progressing to nonalcoholic steatohepatitis (NASH), which is associated with a greater risk for complications of chronic liver disease. Noninvasive testing has been evaluated for diagnosis, risk stratification, disease progression, and assessing response to therapy. The purpose of this narrative review was to outline the current noninvasive testing modalities for the diagnostic evaluation of NAFLD and NASH, while discussing possible markers that could be used for monitoring response to therapies.

The PubMed and Cochrane databases were searched for relevant articles that evaluated the diagnosis of NAFLD/NASH with serum biomarkers and/or imaging.

Serum biomarkers, imaging modalities, and combinations/serial algorithms involved in the diagnosis of NAFLD and NASH are outlined. In addition, noninvasive modalities that have been used for assessing response to therapies in clinical trials are discussed.

Liver biopsy currently remains the gold standard for diagnosis and is often used in clinical trials to assess treatment response. However, developing safe and accessible noninvasive modalities for diagnosis and monitoring will have greater impact and relevance, as biopsy may not always be feasible in all clinical settings.

Fibrosis is the strongest predictor for long-term clinical outcomes among patients with non-alcoholic fatty liver disease (NAFLD). There is growing interest in employing non-invasive methods for risk stratification based on prognosis. FIB-4, NFS and APRI are models commonly used for detecting fibrosis among NAFLD patients. We aimed to synthesize existing literature on the ability of these models in prognosticating NAFLD-related events.

A sensitive search was conducted in two medical databases to retrieve studies evaluating the prognostic accuracy of FIB-4, NFS and APRI among NAFLD patients. Target events were change in fibrosis, liver-related event and mortality. Two reviewers independently performed reference screening, data extraction and quality assessment (QUAPAS tool).

A total of 13 studies (FIB-4:12, NFS: 11, APRI: 10), published between 2013 and 2019, were retrieved. All studies were conducted in a secondary or tertiary care setting, with follow-up ranging from 1 to 20 years. All three markers showed consistently good prognostication of liver-related events (AUC from 0.69 to 0.92). For mortality, FIB-4 (AUC of 0.67-0.82) and NFS (AUC of 0.70-0.83) outperformed APRI (AUC of 0.52-0.73) in all studies. All markers had inconsistent performance for predicting change in fibrosis stage.

FIB-4, NFS, and APRI have demonstrated ability to risk stratify patients for liver-related morbidity and mortality, with comparable performance to a liver biopsy, although more head-to-head studies are needed to validate this. More refined models to prognosticate NAFLD-events may further enhance performance and clinical utility of non-invasive markers.

It is unclear whether the identification of individuals at risk of cirrhosis using non-invasive tests can be improved by repeated measurements. Herein, we tested whether repeated measurements of fibrosis-4 index (FIB-4) could improve the identification of individuals at risk of severe liver disease.

Data were derived from the population-based Swedish AMORIS cohort with baseline examinations from 1985-1996. FIB-4 was calculated at 2 time points within 5 years. Thereafter, we associated changes in FIB-4 with outcomes. Incident severe liver disease data was ascertained through linkage to Swedish national registers until 2011. Hazard ratios (HRs) and CIs for outcomes were calculated using Cox regression.

Of 126,942 individuals with available FIB-4 data, 40,729 (32.1%) underwent a second test within 5 years (mean interval 2.4 years). During 613,376 person-years of follow-up, 581 severe liver disease events were documented (0.95/1,000 person-years). An increase of 1 unit in FIB-4 was associated with an elevated risk of severe liver disease (adjusted hazard ratio [aHR] 1.81; 95% CI 1.67-1.96). Transitioning from a low- or intermediate- to a high-risk group was associated with an increased risk of severe liver disease compared with those consistently in the low-risk group (aHR 7.99 and 8.64, respectively). A particularly increased risk of severe liver disease was found in individuals defined as high risk at both tests (aHR 17.04; 95% CI 11.67-24.88). However, almost half of all events occurred in those consistently in the low-risk group.

Repeated testing of FIB-4 within 5 years improves the identification of individuals at an increased risk of severe liver disease in the general population. However, the sensitivity is comparatively low and improved tests are needed for screening in a general population or primary care setting.

The fibrosis-4 scoring system is often used to estimate the risk of advanced fibrosis in liver diseases. Herein, we found that changes in this score over time are associated with the risk of future severe liver disease in a population-based cohort. However, even if the prediction is improved by repeated testing, the overall ability of the score to predict future events is relatively low.

Noninvasive serum and imaging methods offer accessible, accurate, and safe assessment of fibrosis severity in nonalcoholic fatty liver disease. In contrast, current serum and imaging methods for the prediction of nonalcoholic steatohepatitis are not sufficiently accurate for routine clinical use. Serum fibrosis markers that incorporate direct measures of fibrogenesis (for example, hyaluronic acid) or fibrinolysis are generally more accurate than biomarkers not incorporating direct measures of fibrogenesis. Elastography methods are more accurate than serum markers for fibrosis assessment and particularly for the determination of cirrhosis, but have a significant failure and/or unreliability rate in obese individuals. To overcome this, combining serum and elastography methods in a sequential manner minimizes indeterminate results and maintains accuracy. The accuracy of current noninvasive methods for monitoring fibrosis response to treatment are limited; however, new tools derived from "omic" methodologies offer promise for the future.

Prognostic models to predict individual early postoperative morbidity after liver resection for colorectal liver metastases (CLM) are not available but could enable optimized preoperative patient selection and postoperative surveillance for patients at greater risk of complications. The aim of this study was to establish a prognostic model for the prediction of morbidity after liver resection graded according to Dindo.

N = 679 cases of primary liver resection for CLM were retrospectively analyzed using univariable and multivariable ordinal regression analyses. Receiver operating characteristics curve (ROC) analysis was utilised to assess the sensitivity and specificity of predictions and their potential usefulness as prognostic models. Internal validation of the score was performed using data derived from 129 patients.

The final multivariable regression model revealed lower preoperative levels, a greater number of units of intraoperatively transfused packed red blood cells (pRBCs), longer duration of surgery, and larger metastases to independently influence postoperatively graded morbidity. ROC curve analysis demonstrated that the multivariable regression model is able to predict each individual grade of postoperative morbidity with high sensitivity and specificity. The areas under the receiver operating curves (AUROC) for all of these predictions of individual grades of morbidity were > 0.700, indicating potential usefulness as a predictive model. Moreover, a consistent concordance in Grades I, II, IV, and V according to the classification proposed by Dindo et al. was observed in the internal validation.

This study proposes a prognostic model for the prediction of each grade of postoperative morbidity after liver resection for CLM with high sensitivity and specificity using pre- and intraoperatively available variables.

Non-alcoholic fatty liver disease (NAFLD) is now the most common chronic liver disease in the United States, affecting approximately 1 out of every 4 Americans. NAFLD is a spectrum of disorders including simple steatosis, characterized by the presence of hepatic steatosis with minimal inflammation, and nonalcoholic steatohepatitis (NASH), characterized by the presence of hepatic steatosis with lobular inflammation, ballooning with or without peri-sinusoidal fibrosis. NASH may lead to progressive fibrosis, and therefore, Individuals with NASH and, in particular, hepatic fibrosis are at increased risk for both liver- and cardiovascular-related outcomes compared to those with steatosis alone. New treatments for NASH and hepatic fibrosis are emerging, so now, more than ever, it is important to identify individuals with more advanced disease who may be candidates for therapy. Noninvasive methods to accurately diagnosis, risk stratify, and monitor both NASH and fibrosis are critically needed. Moreover, since clinically relevant outcomes, such as developing end stage liver disease or liver cancer, take many years to develop, reliable surrogate markers of outcome measures are needed to identify and evaluate potential therapies. In this review, we discuss methods to noninvasively diagnosis and monitor both NASH and fibrosis.

Bile acids (BAs) are important signaling molecules acting via the farnesoid X nuclear receptor (FXR) and the membrane G protein-coupled bile acid receptor 1 (GPBAR1). Besides deconjugation of BAs, the oxidoreductive enzymes of colonic bacteria and hepatocytes enable the conversion of BAs into their epimers or dehydrogenated forms. Obeticholic acid (OCA) is the first-in-class BA-derived FXR agonist approved for the treatment of primary biliary cholangitis. Herein, a library of OCA derivatives, including 7-keto, 6-ethylidene derivatives and 3β-epimers, was synthetized and investigated in terms of interactions with FXR and GPBAR1 in transaction assays and evaluated for FXR target genes expression in human hepatocytes and C57BL/6 mice. The derivatives were further subjected to cell-free analysis employing in silico molecular docking and a TR-FRET assay. The conversion of the 3βhydroxy epimer and its pharmacokinetics in mice were studied using LC-MS. We found that only the 3β-hydroxy epimer of OCA (3β-isoOCA) possesses significant activity to FXR in hepatic cells and mice. However, in a cell-free assay, 3β-isoOCA had about 9-times lower affinity to FXR than did OCA. We observed that 3β-isoOCA readily epimerizes to OCA in hepatocytes and murine liver. This conversion was significantly inhibited by the hydroxy-Δ⁵-steroid dehydrogenase inhibitor trilostane. In addition, we found that 3,7-dehydroobeticholic acid is a potent GPBAR1 agonist. We conclude that 3β-isoOCA significantly activates FXR due to its epimerization to the more active OCA by hepatic metabolism. Other modifications as well as epimerization on the C3/C7 positions and the introduction of 6-ethylidene in the CDCA scaffold abrogate FXR agonism and alleviate GPBAR1 activation.

Pirfenidone (PFD), an oral antifibrotic drug, has been authorized by the EMA and FDA for treatment of idiopathic pulmonary fibrosis. Few studies have addressed its use in advanced liver fibrosis (ALF). We evaluated a prolonged-release formulation (PR-PFD) plus standard of care on disease progression in ALF.

281 ALF patients from 12 centers receiving PR-PFD (600 mg bid) were screened; 122 completed 1 year of treatment. Additionally, 74 patients received only standard of care regimen. Average age was 64 ± 12 years, 58% female. 43.5% had fatty liver disease (NAFLD), 22.5% viral hepatitis C (VHC), 17% autoimmune hepatitis (AIH), and 17% alcoholic liver disease (ALD). Baseline fibrosis was F4 in 74% and F3 in 26%. Antifibrotic effects were assessed by transient elastography (Fibroscan®) and Fibro Test® (FT); Cytokines and PFD plasma levels were tracked and quality of life evaluated.

We found a significant reduction in fibrosis in 35% of PR-PFD patients and only in 4.1% in non PR-PFD patients. Child-Pugh score improved in 29.7%. Biochemical values remained stable; 40.6% and 43.3% decreased ALT or AST, respectively. TGFβ1 (pg/mL) levels were lower in PFD-treated patients. PFD serum concentration (µg/mL) was higher (8.2 ± 1.7) in fibrosis regression profile (FRP) patients compared to fibrosis progression profile (FPP) patients (4.7 ± 0.3 µg/mL, p < 0.01). 12% reported transient burning or nausea and 7% photosensitivity. Quality of life (Euro-Qol scale) improved from 62 ± 5 to 84 ± 3 (p < 0.001) and from 32 ± 3 to 42 ± 2 (p < 0.008) (FACIT scale).

PR-PFD is efficacious and safe in ALF and associated with promising antifibrotic effects.

Clinical trial number: NCT04099407.

Over the past two decades, bile acids (BAs) have become established as important signaling molecules that enable fine-tuned inter-tissue communication from the liver, their site of production, over the intestine, where they are modified by the gut microbiota, to virtually any organ, where they exert their pleiotropic physiological effects. The chemical variety of BAs, to a large extent determined by the gut microbiome, also allows for a complex fine-tuning of adaptive responses in our body. This review provides an overview of the mechanisms by which BA receptors coordinate several aspects of physiology and highlights new therapeutic strategies for diseases underlying pathological BA signaling.