The Evolving Role of Liver Biopsy in Non-alcoholic Fatty Liver Disease

Predictive performance of noninvasive factors for liver fibrosis in severe obesity: a screening based on machine learning models

Objectives

Liver fibrosis resulting from nonalcoholic fatty liver disease (NAFLD) and metabolic disorders is highly prevalent in patients with severe obesity and poses a significant health challenge. However, there is a lack of data on the effectiveness of noninvasive factors in predicting liver fibrosis. Therefore, this study aimed to assess the relationship between these factors and liver fibrosis through a machine learning approach.

Methods

This study involved 512 patients who underwent bariatric surgery at an outpatient clinic in Mashhad, Iran, between December 2015 and September 2021. Patients were divided into fibrosis and non-fibrosis groups and demographic, clinical, and laboratory variables were applied to develop four machine learning models: Naive Bayes (NB), logistic regression (LR), Neural Network (NN) and Support Vector Machine (SVM).

Results

Among the 28 variables considered, six variables including (fasting blood sugar (FBS), skeletal muscle mass (SMM), hemoglobin, alanine transaminase (ALT), aspartate transaminase (AST) and triglycerides) showed high area under the curve (AUC) values for the diagnosis of liver fibrosis using 2D shear wave elastography (SWE) with LR (0.73, 95% CI: 0.65, 0.81) and SVM (0.72, 59% CI: 0.64, 0.80) models. Furthermore, the highest sensitivities were reported with SVM (0.83, 95% CI: 0.72, 0.91) and NB (0.66, 95% CI: 0.53, 0.77) models, respectively.

Conclusion

The predictive performance of six noninvasive factors of liver fibrosis was significantly superior to other factors, showing high application and accuracy in the diagnosis and prognosis of liver fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-025-01564-1.

Noninvasive identification of metabolic dysfunction-associated steatohepatitis (INFORM MASH): a retrospective cohort and disease modeling study

BACKGROUND

Using common clinical parameters, we aimed to noninvasively identify and predict metabolic dysfunction-associated steatohepatitis (MASH)/MASH with clinically significant fibrosis.

RESEARCH DESIGN AND METHODS

Patients aged ≥18 with electronic health record (EHR) documented liver function tests and liver biopsies between 2016 and 2021 were retrospectively identified from the Geisinger Health System Research Liver Registry. MASH cases were confirmed using the nonalcoholic fatty liver disease (NAFLD) activity score. Training and validation datasets were used to create an algorithm/predictive model assessing EHR-derived predictors of MASH/MASH with clinically significant fibrosis (fibrosis stage F2-F4). Predictive accuracy was evaluated using the area under the curve.

RESULTS

The analysis included 2698 patients. We created a composite likelihood score using variables significant for MASH and/or MASH with clinically significant fibrosis: liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST]), prior year AST, metabolic disease, pulse (heart rate), and body mass index. The score had higher sensitivity and specificity for predicting MASH than Fibrosis-4 (FIB-4) Index, AST to platelet ratio index (APRI), and NAFLD fibrosis score (NFS); sensitivity and specificity were comparable to FIB-4 and APRI for predicting MASH with clinically significant fibrosis but superior to NFS.

CONCLUSION

The composite likelihood score could potentially be a tool for early MASH screening.

Noninvasive Assessment of the Severity of Liver Fibrosis in MASLD Patients with Long-Standing Type 2 Diabetes

BACKGROUND

Type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated steatotic liver disease (MASLD), which have a reciprocal relationship compounded by obesity, are highly prevalent in the Middle East affecting morbidity, mortality, and healthcare costs.

OBJECTIVE

This study aimed to assess the severity of MASLD and liver fibrosis among adult Emirati patients with long-standing T2DM.

DESIGN AND PARTICIPANTS

This cross-sectional study used noninvasive methods to assess the severity of MASLD and fibrosis progression in an adult cohort of Emirati patients (N = 546) with a mean T2DM duration of 16 years.

MAIN MEASURES

Fatty liver infiltration was assessed by hepatic steatosis index (HSI), while fibrosis was assessed by the fibrosis-4 (FIB-4) index and aspartate aminotransferase/platelet ratio index (APRI). Of those, 108 patients were randomly subjected to ultrasound-based FibroScan® to assess controlled attenuation parameter (CAP) and liver stiffness measurement (LSM).

KEY RESULTS

All patients had fatty liver with ~ 83% being categorized as having severe steatosis. Serum-based fibrosis biomarker panels detected significant liver fibrosis in ~ 2.5% of these patients. The APRI appeared to be more restrictive in detecting moderate fibrosis (1.5%) than the FIB-4 index (25.5%). CAP significantly correlated with the LSM, indicating that the two methods contributed to the same underlying pathophysiology. Liver steatosis was more severe in female patients, who were older and had a higher body mass index (BMI) than those with moderate or no significant fibrosis. They also had higher serum liver enzymes and were more likely to have age-related changes in kidney function. Interestingly, severity of both steatosis and fibrosis remained unaffected by age and duration of T2D except for fibrosis severity detected by FibroScan®.

CONCLUSIONS

This study highlights the critical need for routine screening of MASLD among Emirati patients with long-standing T2DM, given the high point prevalence of severe steatosis (~ 83%), predominantly among women in this population.

Advanced Imaging Techniques for Assessing Fat, Iron, and Fibrosis in Chronic Liver Disease

Imaging plays a critical role in the management of chronic liver disease (CLD) because it is a safe and painless method to assess liver health. The widely used imaging techniques include ultrasound, computed tomography and magnetic resonance imaging. These techniques allow the measurement of fat deposition, iron content, and fibrosis, replacing invasive liver biopsies in many cases. Early detection and treatment of fibrosis are crucial, as the disease can be reversed in its early stages. Imaging also aids in guiding treatment decisions and monitoring disease progression. In this review, we describe the most common imaging manifestations of liver disease and the current state-of-the-art imaging techniques for the evaluation of liver fat, iron, and fibrosis.

Influence of Adherence to the Mediterranean Diet and Level of Physical Activity with Liver Steatosis in People Aged > 50 Years and with a BMI > 25 kg/m2: Association with Biochemical Markers

BACKGROUND

The main objective of this study is to determine the accuracy of different biochemical markers of hepatic steatosis and to correlate liver steatosis with adherence to the Mediterranean diet and level of physical activity.

METHODS

A cross-sectional study was carried out, including subjects over 50 years of age, with a BMI > 25 kg/m2, but excluding any patient with documented hepatic pathology other than hepatic steatosis. Participants were divided into two groups: patients with hepatic steatosis diagnosed by ultrasound (SG) and a control group of individuals without hepatic steatosis (CG). The level of physical activity was recorded by the IPAQ-SF questionnaire and the adherence to the Mediterranean diet was recorded using the PREDIMED questionnaire. Biochemical markers analyzed included the Hepatic steatosis index (HSI), AST-to-Platelet ratio (APRI) and Fibrosis-4 (FIB-4).

RESULTS

A total of 116 patients were included, 71 belonging to the SG and 45 to the CG. A total of 58.6% of the patients showed low adherence to the Mediterranean diet, 35.4% moderate adherence and 6% high adherence. The median estimated physical activity was 495 METS, with most participants reporting light activity. In the SG, significantly higher HSI values were observed (p < 0.001). A cut-off point of a HSI of 40 was established, with a sensitivity of 73.2% and a specificity of 65.8%. Significantly higher FIB-4 values (p = 0.039) were also observed in the SG. A cut-off point of FIB-4 was set at 0.27, with a sensitivity of 69% and a specificity of 57.9%. Patients in the SG showed lower scores in the PREDIMED. Patients in the SG tended to show lower METS scores. However, the higher number of patients with intense activity in the CG group stands out (p = 0.008).

CONCLUSIONS

The HSI and FIB-4 showed a significant correlation with liver steatosis. Hepatic steatosis is associated with low adherence to the Mediterranean diet and patients with hepatic steatosis tended to have lower METS scores.

Circulating Ferritin in Patients with Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

Objectives

To synthesize data on circulating ferritin between patients with histologically confirmed nonalcoholic fatty liver disease (NAFLD) and non-NAFLD controls.

Methods

A systematic literature search was conducted in PubMed, Scopus, and the Cochrane Library. Thirty-one studies comprising data on 5631 individuals (2929 biopsy-proven NAFLD patients and 2702 controls) were included in the meta-analysis.

Results

Higher circulating ferritin levels were observed in NAFLD patients than in controls [standardized mean difference (SMD) 1.14; 95% confidence interval (95% CI) 0.73-1.55], in patients with simple nonalcoholic fatty liver (NAFL) than in controls (SMD 0.57; 95% CI 0.34-0.80), in patients with nonalcoholic steatohepatitis (NASH) than in controls (SMD 0.95; 95% CI 0.69-1.22), and in NASH than in NAFL patients (SMD 0.62; 95% CI 0.25-0.99). There was moderate-to-high heterogeneity among studies in the above pairs of comparisons (I2 = 68-97%); no risk of publication bias was observed by Egger's test (P = 0.81, P = 0.72, P = 0.59, P = 0.42, respectively). The heterogeneity was reduced in the subgroup of biopsy-proven controls in all pairs of comparisons (I2 = 0-65%). The heterogeneity was also reduced after excluding studies with the Newcastle-Ottawa Scale (NOS) score <7 (n = 10) for the comparison of NAFLD patients vs. controls (I2 = 54%, P = 0.02). The meta-regression analysis revealed that the male ratio was positively associated with ferritin SMD in the comparison between NAFLD patients and controls and accounted for 32.7% (P = 0.002) of the heterogeneity in this pair of comparison.

Conclusions

Circulating ferritin was higher in NAFLD (or NAFL or NASH) patients compared with controls. Higher levels of circulating ferritin were also associated with the severity of the disease, which, however, should be cautiously interpreted.PROSPERO registration ID: CRD42022354025.

Liver Biopsy: To Do or Not to Do - A Single-Center Study

INTRODUCTION

A variety of liver disorders are associated with characteristic histopathological findings that help in their diagnosis and treatment. However, percutaneous liver biopsy (PLB) is prone to limitations and complications. We evaluated all PLBs done in our hospital in a 13-year period, aiming to assess PLB's utility and complications.

METHODS

All PLBs conducted in an internal medicine department of a tertiary university hospital in Athens, Greece, during a 13-year period were reviewed. Recorded data included demographic characteristics, laboratory results acquired on biopsy day, indication for liver biopsy, and occurrence of side effects. All patients were followed for 1 month post-hospital discharge for possible PLB-related complications.

RESULTS

A total of 261 patients underwent PLB during the study period. The commonest indication of PLB was investigation of liver mass, followed by transaminasemia. PLB assisted in setting a diagnosis in 218 patients and was unhelpful in only 43, in 14 of them due to inadequate or inappropriate biopsy specimen. Complications attributable to PLB were rare, with 10 patients exhibiting pain, either at biopsy site or in the right shoulder, and 3 having bleeding episodes; no deaths were noted.

CONCLUSIONS

Our study shows that PLB is still a powerful diagnostic tool in everyday practice, provided it is used when indicated.

An Ethyl Acetate Extract of Eryngium carlinae Inflorescences Attenuates Oxidative Stress and Inflammation in the Liver of Streptozotocin-Induced Diabetic Rats

Secondary metabolites such as flavonoids are promising in the treatment of non-alcoholic fatty liver disease (NAFLD), which is one of the complications of diabetes due to oxidative stress and inflammation. Some plants, such as Eryngium carlinae, have been investigated regarding their medicinal properties in in vitro and in vivo assays, showing favorable results for the treatment of various diseases such as diabetes and obesity. The present study examined the antioxidant and anti-inflammatory effects of the phenolic compounds present in an ethyl acetate extract of the inflorescences of Eryngium carlinae on liver homogenates and mitochondria from streptozotocin (STZ)-induced diabetic rats. Phenolic compounds were identified and quantified by UHPLC-MS. In vitro assays were carried out to discover the antioxidant potential of the extract. Male Wistar rats were administered with a single intraperitoneal injection of STZ (45 mg/kg) and were given the ethyl acetate extract at a level of 30 mg/kg for 60 days. Phytochemical assays showed that the major constituents of the extract were flavonoids; in addition, the in vitro antioxidant activity was dose dependent with IC50 = 57.97 mg/mL and IC50 = 30.90 mg/mL in the DPPH and FRAP assays, respectively. Moreover, the oral administration of the ethyl acetate extract improved the effects of NAFLD, decreasing serum and liver triacylglycerides (TG) levels and oxidative stress markers and increasing the activity of the antioxidant enzymes. Likewise, it attenuated liver damage by decreasing the expression of NF-κB and iNOS, which lead to inflammation and liver damage. We hypothesize that solvent polarity and consequently chemical composition of the ethyl acetate extract of E. carlinae, exert the beneficial effects due to phenolic compounds. These results suggest that the phenolic compounds of the ethyl acetate extract of E. carlinae have antioxidant, anti-inflammatory, hypolipidemic, and hepatoprotective activity.

Pro-Neurotensin as a Potential Novel Diagnostic Biomarker for Detection of Nonalcoholic Fatty Liver Disease

BACKGROUND AND AIMS

Currently, liver biopsy is the gold standard method for diagnosis of non-alcoholic fatty liver severity. It is critical to develop non-invasive diagnostic method to diagnose nonalcoholic fatty liver rather than invasive techniques. Our case-control study was to address the value of circulating miRNA-122 and serum pro-neurotensin as a potential non-invasive biomarker for the diagnosis of non-alcoholic fatty acid diseases.

METHODS

Clinical assessment, laboratory investigations, and anthropometric measurements were reported for 157 patients with proven NAFLD. Apparently, healthy participants (n=100) were enrolled as a control group. Serum samples were tested for micro-RNAs-122 and pro-neurotensin.

RESULTS

Compared with the control subjects, both mi-RNA-122 and serum proneurotensin levels were increased in NAFLD (p<0.001) and at a cut-off ≥6.83, mi-RNA-122 had 51.0% sensitivity, 70.0% specificity to differentiate NAFLD from healthy controls, while serum proneurotensin had 80.0% sensitivity and 80.0% specificity at a cutoff ≥108.

CONCLUSION

The circulating pro-neurotensin might be used as a novel biomarker for diagnosis of patients with NAFLD, wherefore the integration of a circulating mi-RNA-122 and serum pro-neurotensin could be beneficial to diagnose NAFLD cases. Large-scale studies are needed to investigate the possible role of mi-RNA-122 and pro-neurotensin in the development, progression, and prognosis of NAFLD and NASH.

Strategies to Diagnose Nonalcoholic Steatohepatitis: A Novel Approach to Take Advantage of Pharmacokinetic Alterations

Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD) and is diagnosed by a liver biopsy. Because of the invasiveness of a biopsy, the majority of patients with NASH are undiagnosed. Additionally, the prevalence of NAFLD and NASH creates the need for a simple screening method to differentiate patients with NAFLD versus NASH. Noninvasive strategies for diagnosing NAFLD versus NASH have been developed, typically relying on imaging techniques and endogenous biomarker panels. However, each technique has limitations, and none can accurately predict the associated functional impairment of drug metabolism and disposition. The function of several drug-metabolizing enzymes and drug transporters has been described in NASH that impacts drug pharmacokinetics. The aim of this review is to give an overview of the existing noninvasive strategies to diagnose NASH and to propose a novel strategy based on altered pharmacokinetics using an exogenous biomarker whose disposition and elimination pathways are directly impacted by disease progression. Altered disposition of safe and relatively inert exogenous compounds may provide the sensitivity and specificity needed to differentiate patients with NAFLD and NASH to facilitate a direct indication of hepatic impairment on drug metabolism and prevent subsequent adverse drug reactions. SIGNIFICANCE STATEMENT: This review provides an overview of the main noninvasive techniques (imaging and panels of biomarkers) used to diagnose NAFLD and NASH along with a biopsy. Pharmacokinetic changes have been identified in NASH, and this review proposes a new approach to predict NASH and the related risk of adverse drug reactions based on the assessment of drug elimination disruption using exogenous biomarkers.

Assessment of hepatic fatty acids during non-alcoholic steatohepatitis progression using magnetic resonance spectroscopy

INTRODUCTION AND OBJECTIVES

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of liver abnormalities including steatosis, steatohepatitis, fibrosis, and cirrhosis. Liver biopsy remains the gold standard method to determine the disease stage in NAFLD but is an invasive and risky procedure. Studies have previously reported that changes in intrahepatic fatty acids (FA) composition are related to the progression of NAFLD, mainly in its early stages. The aim of this study was to characterize the liver FA composition in mice fed a Choline-deficient L-amino-defined (CDAA) diet at different stages of NAFLD using magnetic resonance spectroscopy (MRS).

METHODS

We used in-vivo MRS to perform a longitudinal characterization of hepatic FA changes in NAFLD mice for 10 weeks. We validated our findings with ex-vivo MRS, gas chromatography-mass spectrometry and histology.

RESULTS

In-vivo and ex-vivo results showed that livers from CDAA-fed mice exhibit a significant increase in liver FA content as well as a change in FA composition compared with control mice. After 4 weeks of CDAA diet, a decrease in polyunsaturated and an increase in monounsaturated FA were observed. These changes were associated with the appearance of early stages of steatohepatitis, confirmed by histology (NAFLD Activity Score (NAS) = 4.5). After 10 weeks of CDAA-diet, the liver FA composition remained stable while the NAS increased further to 6 showing a combination of early and late stages of steatohepatitis.

CONCLUSION

Our results suggest that monitoring lipid composition in addition to total water/fat with MRS may yield additional insights that can be translated for non-invasive stratification of high-risk NAFLD patients.

MAFLD/NAFLD Biopsy-Free Scoring Systems for Hepatic Steatosis, NASH, and Fibrosis Diagnosis

Metabolic dysfunction-associated fatty liver disease (MAFLD), formerly known as nonalcoholic fatty liver disease, is the most prevalent liver disorder worldwide. Historically, its diagnosis required biopsy, even though the procedure has a variable degree of error. Therefore, new non-invasive strategies are needed. Consequently, this article presents a thorough review of biopsy-free scoring systems proposed for the diagnosis of MAFLD. Similarly, it compares the severity of the disease, ranging from hepatic steatosis (HS) and nonalcoholic steatohepatitis (NASH) to fibrosis, by contrasting the corresponding serum markers, clinical associations, and performance metrics of these biopsy-free scoring systems. In this regard, defining MAFLD in conjunction with non-invasive tests can accurately identify patients with fatty liver at risk of fibrosis and its complications. Nonetheless, several biopsy-free scoring systems have been assessed only in certain cohorts; thus, further validation studies in different populations are required, with adjustment for variables, such as body mass index (BMI), clinical settings, concomitant diseases, and ethnic backgrounds. Hence, comprehensive studies on the effects of age, morbid obesity, and prevalence of MAFLD and advanced fibrosis in the target population are required. Nevertheless, the current clinical practice is urged to incorporate biopsy-free scoring systems that demonstrate adequate performance metrics for the accurate detection of patients with MAFLD and underlying conditions or those with contraindications of biopsy.

Prediction of Cardiovascular Risk Using Nonalcoholic Fatty Liver Disease Scoring Systems

This study aimed to determine whether nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for CVD and to identify the most useful NAFLD diagnostic tool for predicting CVD. Data from a total of 23,376 Korean adults without established CVD were analyzed. Cardiovascular risk was calculated using the Framingham Risk Score (FRS) 2008. The presence of NAFLD was defined as moderate-to-severe fatty liver disease diagnosed by ultrasonography. Scores for fatty liver were calculated using four NAFLD scoring systems (Fatty Liver Index, FLI; Hepatic Steatosis Index, HSI; Simple NAFLD Score, SNS; Comprehensive NAFLD Score, CNS), and were compared and analyzed according to cardiovascular risk group. Using the FRS, 67.4% of participants were considered to be at low risk of CVD, 21.5% at intermediate risk, and 11.1% at high risk. As the risk of CVD increased, both the prevalence of NAFLD and the score from each NAFLD scoring system increased significantly (p < 0.001). In the unadjusted analysis, the CNS had the strongest association with high CVD risk; in the adjusted analysis, the FLI score was most strongly associated with high CVD risk. Fatty liver is an important independent risk factor for CVD. Therefore, the available NAFLD scoring systems could be utilized to predict CVD.

Evolution of the liver biopsy and its future

Liver biopsies are commonly used to evaluate a wide variety of medical disorders, including neoplasms and post-transplant complications. However, its use is being impacted by improved clinical diagnosis of disorders, and non-invasive methods for evaluating liver tissue and as a result the indications of a liver biopsy have undergone major changes in the last decade. The evolution of highly effective treatments for some of the common indications for liver biopsy in the last decade (e.g., viral hepatitis B and C) has led to a decline in the number of liver biopsies in recent years. At the same time, the emergence of better technologies for histologic evaluation, tissue content analysis and genomics are among the many new and exciting developments in the field that hold great promise for the future and are going to shape the indications for a liver biopsy in the future. Recent advances in slide scanners now allow creation of "digital/virtual" slides that have image of the entire tissue section present in a slide [whole slide imaging (WSI)]. WSI can now be done very rapidly and at very high resolution, allowing its use in routine clinical practice. In addition, a variety of technologies have been developed in recent years that use different light sources and/or microscopes allowing visualization of tissues in a completely different way. One such technique that is applicable to liver specimens combines multiphoton microscopy (MPM) with advanced clearing and fluorescent stains known as Clearing Histology with MultiPhoton Microscopy (CHiMP). Although it has not yet been extensively validated, the technique has the potential to decrease inefficiency, reduce artifacts, and increase data while being readily integrable into clinical workflows. Another technology that can provide rapid and in-depth characterization of thousands of molecules in a tissue sample, including liver tissues, is matrix assisted laser desorption/ionization (MALDI) mass spectrometry. MALDI has already been applied in a clinical research setting with promising diagnostic and prognostic capabilities, as well as being able to elucidate mechanisms of liver diseases that may be targeted for the development of new therapies. The logical next step in huge data sets obtained from such advanced analysis of liver tissues is the application of machine learning (ML) algorithms and application of artificial intelligence (AI), for automated generation of diagnoses and prognoses. This review discusses the evolving role of liver biopsies in clinical practice over the decades, and describes newer technologies that are likely to have a significant impact on how they will be used in the future.

Performance of Noninvasive Liver Fibrosis Tests in Morbidly Obese Patients with Nonalcoholic Fatty Liver Disease

Background

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent in morbidly obese patients, and fibrosis is an independent predictor of mortality. Noninvasive tests (NITs) are being developed for the detection of advanced fibrosis (AF).

Purpose

To assess the performance of three NITs (NAFLD fibrosis score, NFS, fibrosis-4 index, FIB-4, and aspartate aminotransferase-to-platelet ratio, APRI), in the identification of AF among morbidly obese patients.

Materials and Methods

Patients, who underwent bariatric surgery between 2004 and 2009 and had liver biopsy, were included. Fibrosis stages ≥ F2 and ≥ F3 were defined as significant and AF, respectively. Published and optimal thresholds (Youden index) for NFS, FIB-4 and APRI, sensitivity, specificity, positive and negative predictive values (PPV-NPV), and area under the receiver operator curves (AUROC) were evaluated.

Results

Among 584 patients (mean age 43.3 ± 11.3 years, 21.2% male, 75% white, mean BMI 45.5 ± 8.80), 31.7% had NASH. Stages distributions were F1 = 68.1%, F2 = 16.4%, F3 = 8%, and F4 = 3.2%. At published thresholds, all 3 NITs performed poorly for detection of AF, with AUROC < 0.62. Overall performance at optimal thresholds improved to 0.68, 0.72, and 0.74 for NFS, FIB-4, and APRI, respectively. At optimal thresholds, all tests had good NPV (94.4–95.9%) but low PPV (24.2–32.5%). Combinations of the tests did not improve their performance.

Conclusions

NFS, FIB-4, and APRI fall short to detect advanced fibrosis but valuable for excluding advanced fibrosis. More research is needed to develop new NITs with high positive predictive value.

Electronic supplementary material

The online version of this article (10.1007/s11695-020-04996-1) contains supplementary material, which is available to authorized users.

Usefulness of collagen type IV in the detection of significant liver fibrosis in nonalcoholic fatty liver disease

INTRODUCTION/AIMS

Liver fibrosis assessment is a key issue in the evaluation of nonalcoholic fatty liver disease (NAFLD) patients. In the present study, we aimed to validate a noninvasive marker panel to assess significant and advanced fibrosis in these patients.

METHOD

126 biopsy-proven NAFLD patients were included. NAFLD diagnosis was based on histological criteria. Fibrosis stages were determined according to NASH-Clinical Research Network criteria. Clinical and laboratorial data were collected during the interval of three months before or after liver biopsy. Histological fibrosis stages were classified as significant fibrosis (F2-F4) and advanced fibrosis (F3-F4). Five serum biomarkers [hyaluronic acid (HA), collagen type IV (cIV), procollagen type III (PC III), laminin (LN) and cholylglycine (CG)] were assessed by chemiluminescence immunoassays.

RESULTS

Most patients were female (61.61%), mean age: 55.7 ± 9.13 years old and mean BMI was 32.1 ± 5.9 kg/m2. Prevalence of diabetes, dyslipidemia, arterial hypertension, and metabolic syndrome was 68.75%, 82.29%, 63.54% and 81.05%, respectively. Patients with cIV above 30 ng/mL had a 5.57-times (IC: 1.86-16.69) the chance of having significant fibrosis and 7.61-times (IC: 2.27-25.54) the chance of having advanced fibrosis versus patients with values below 30 ng/mL. HA, PC III, LN and CG did not detect the presence of significant and advanced fibrosis. The AUROC of clV for detection of significant (0.718) and advanced fibrosis (0.791) was better than that of other serum biomarkers.

CONCLUSION

Type 4 collagen could predict the presence of significant and advanced fibrosis in NAFLD patients and it would be a useful tool in routine clinical practice.

Extracellular Vesicles in NAFLD/ALD: From Pathobiology to Therapy

In recent years, knowledge on the biology and pathobiology of extracellular vesicles (EVs) has exploded. EVs are submicron membrane-bound structures secreted from different cell types containing a wide variety of bioactive molecules (e.g., proteins, lipids, and nucleic acids (coding and non-coding RNA) and mitochondrial DNA). EVs have important functions in cell-to-cell communication and are found in a wide variety of tissues and body fluids. Better delineation of EV structures and advances in the isolation and characterization of their cargo have allowed the diagnostic and therapeutic implications of these particles to be explored. In the field of liver diseases, EVs are emerging as key players in the pathogenesis of both nonalcoholic liver disease (NAFLD) and alcoholic liver disease (ALD), the most prevalent liver diseases worldwide, and their complications, including development of hepatocellular carcinoma. In these diseases, stressed/damaged hepatocytes release large quantities of EVs that contribute to the occurrence of inflammation, fibrogenesis, and angiogenesis, which are key pathobiological processes in liver disease progression. Moreover, the specific molecular signatures of released EVs in biofluids have allowed EVs to be considered as promising candidates to serve as disease biomarkers. Additionally, different experimental studies have shown that EVs may have potential for therapeutic use as a liver-specific delivery method of different agents, taking advantage of their hepatocellular uptake through interactions with specific receptors. In this review, we focused on the most recent findings concerning the role of EVs as new structures mediating autocrine and paracrine intercellular communication in both ALD and NAFLD, as well as their potential use as biomarkers of disease severity and progression. Emerging therapeutic applications of EVs in these liver diseases were also examined, along with the potential for successful transition from bench to clinic.

The diagnostic accuracy of liver fibrosis in non-viral liver diseases using acoustic radiation force impulse elastography: A systematic review and meta-analysis

BACKGROUND

Acoustic radiation force impulse (ARFI) imaging is an ultrasound-based elastography method that has been studied in the staging of hepatic fibrosis, especially in chronic hepatitis. However, the diagnostic accuracy of ARFI in non-viral hepatopathies, such as autoimmune hepatitis and non-alcoholic fatty liver disease, has not been systematically determined.

AIM

To systematically assess the diagnostic accuracy of ARFI in non-viral hepatopathies.

METHODS

The databases of PubMed, Embase, Cochrane Library and clinicaltrials.gov were systematically searched for candidate studies reporting the diagnostic accuracy of ARFI for hepatic fibrosis. The pooled estimates of the sensitivity, specificity, diagnostic odds ratio, and positive and negative likelihood ratios were calculated with the summary receiver operating curve (sROC) performed using STATA software.

RESULTS

In detail, a total of 29 diagnostic studies were included for further analysis. The quality of the included studies was relatively high using QUADAS method. The pooled sensitivity and specificity were 0.79 (0.73, 0.83) and 0.81 (0.75, 0.86), with AUROC 0.87 (0.83, 0.89) for the staging of significant fibrosis (F≥2). Meanwhile, for the staging of severe fibrosis (F≥3), the pooled sensitivity and specificity were 0.92 (0.87, 0.95) and 0.85 (0.80, 0.89), with AUROC 0.94 (0.92, 0.96). Furthermore, the pooled sensitivity and specificity were 0.89 (0.79, 0.95) and 0.89 (0.85, 0.92), with AUROC 0.94 (0.92, 0.96) for ARFI in staging cirrhosis (F = 4), which were similar to the data for severe fibrosis. No significant publication bias was present in this study.

CONCLUSION

This meta-analysis demonstrated that ARFI exerted satisfactory diagnostic performance in staging non-viral hepatic fibrosis, especially severe fibrosis (F≥3) and cirrhosis (F = 4).

Whole Slide Imaging and Its Applications to Histopathological Studies of Liver Disorders

Histological analysis of hepatic tissue specimens is essential for evaluating the pathology of several liver disorders such as chronic liver diseases, hepatocellular carcinomas, liver steatosis, and infectious liver diseases. Manual examination of histological slides on the microscope is a classically used method to study these disorders. However, it is considered time-consuming, limited, and associated with intra- and inter-observer variability. Emerging technologies such as whole slide imaging (WSI), also termed virtual microscopy, have increasingly been used to improve the assessment of histological features with applications in both clinical and research laboratories. WSI enables the acquisition of the tissue morphology/pathology from glass slides and translates it into a digital form comparable to a conventional microscope, but with several advantages such as easy image accessibility and storage, portability, sharing, annotation, qualitative and quantitative image analysis, and use for educational purposes. WSI-generated images simultaneously provide high resolution and a wide field of observation that can cover the entire section, extending any single field of view. In this review, we summarize current knowledge on the application of WSI to histopathological analyses of liver disorders as well as to understand liver biology. We address how WSI may improve the assessment and quantification of multiple histological parameters in the liver, and help diagnose several hepatic conditions with important clinical implications. The WSI technical limitations are also discussed.

Concurrent nonalcoholic fatty liver disease and type 2 diabetes: diagnostic and therapeutic considerations

Introduction: The relationship between nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) is complex and bidirectional. NAFLD increases the risk of incident diabetes and is very prevalent in T2DM patients and T2DM is an aggravating factor for NAFLD. Timely T2DM diagnosis and treatment in subjects with NAFLD and diagnosis, staging and treatment of NAFLD in those with T2DM are critical issues. Areas covered: PubMed/MEDLINE was searched for articles related to concomitant occurrence of NAFLD and T2DM between January 2013 and May 2019. Areas covered included epidemiological, diagnostic and therapeutic aspects. Expert opinion: there is a need for increased awareness on NAFLD adding liver disease as an end-organ complication of T2DM. Emphasis on use of simple non-invasive tools to triage patients with potentially severe liver disease should be made. Management of patients with NAFLD and T2DM relies on lifestyle optimization to achieve significant weight loss. Currently, there is no drug approved for treatment of NAFLD in patients with T2DM although Vitamin E and pioglitazone might be used in selected patients. Approved diabetic medications hold promise for NAFLD treatment and several liver-specific drugs are in evaluation clinical trials. A combination approach will likely represent the future of NAFLD therapeutics.

Validation of biochemical scores for liver steatosis before and 1 year after sleeve gastrectomy

BACKGROUND

Bariatric surgery is a potential treatment for liver steatosis in morbidly obese patients, showing an improvement in approximately 90% of cases of fatty liver after surgery. Liver biopsy is the gold standard method to monitor liver steatosis. Imaging tests, such as magnetic resonance (MR) spectroscopy, have shown a good accuracy in the diagnosis of liver steatosis. Several biochemical markers have been proposed as diagnostic alternatives to evaluate fatty liver.

OBJECTIVES

The aim of this study was to analyze the potential of different biochemical markers for evaluating liver steatosis in morbidly obese patients before and after undergoing sleeve gastrectomy.

SETTING

Garcilaso Clinic, Madrid, Spain.

METHODS

A prospective observational study of patients undergoing sleeve gastrectomy was performed. Diverse biochemical markers were assessed and correlated with MR spectroscopy as the diagnostic method for liver steatosis.

RESULTS

One hundred consecutive patients were included. Twelve months after surgery, mean body mass index was 28.3 ± 3.7 kg/m² and mean excess weight loss 82.5% ± 17.8%. Preoperatively, 67% of the patients had liver steatosis and 12 months after surgery the steatosis rate was reduced to 23%, as measured by MR spectroscopy. A significant direct correlation could only be observed between the percentage of lipid content, determined by MR spectroscopy and the liver fat score, at baseline and in the preoperative score. A cut-off point for liver fat score to determine the presence of liver steatosis was established at 1.22, for baseline and postoperative determinations.

CONCLUSION

The liver fat score is the most accurate biochemical score to correlate with the percentage of lipid content of the liver, determined by MR spectroscopy.