Transient elastography (TE), shear wave elastography, and/or magnetic resonance elastography (MRE), each providing liver stiffness measurement (LSM), are the most studied imaging-based noninvasive liver disease assessment (NILDA) techniques. To support the American Association for the Study of Liver Diseases guidelines on NILDA, we summarized the evidence on the accuracy of these LSM methods to stage liver fibrosis (F).

A comprehensive search for studies assessing LSM by TE, shear wave elastography, or MRE for the identification of significant fibrosis (F2-4), advanced fibrosis (F3-4), or cirrhosis (F4), using histopathology as the standard of reference by liver disease etiology in adults or children from inception to April 2022 was performed. We excluded studies with <50 patients with a single disease entity and mixed liver disease etiologies (with the exception of HCV/HIV coinfection). Out of 9447 studies, 240 with 61,193 patients were included in this systematic review. In adults, sensitivities for the identification of F2-4 ranged from 51% to 95%, for F3-4 from 70% to 100%, and for F4 from 60% to 100% across all techniques/diseases, whereas specificities ranged from 36% to 100%, 74% to 100%, and 67% to 99%, respectively. The largest body of evidence available was for TE; MRE appeared to be the most accurate method. Imaging-based NILDA outperformed blood-based NILDA in most comparisons, particularly for the identification of F3-4/F4. In the pediatric population, imaging-based NILDA is likely as accurate as in adults.

LSM from TE, shear wave elastography, and MRE shows acceptable to outstanding accuracy for the detection of liver fibrosis across various liver disease etiologies. Accuracy increased from F2-4 to F3-4 and was the highest for F4. Further research is needed to better standardize the use of imaging-based NILDA, particularly in pediatric liver diseases.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed non-alcoholic fatty liver disease (NAFLD), is defined as steatotic liver disease (SLD) in the presence of one or more cardiometabolic risk factor(s) and the absence of harmful alcohol intake. The spectrum of MASLD includes steatosis, metabolic dysfunction-associated steatohepatitis (MASH, previously NASH), fibrosis, cirrhosis and MASH-related hepatocellular carcinoma (HCC). This joint EASL-EASD-EASO guideline provides an update on definitions, prevention, screening, diagnosis and treatment for MASLD. Case-finding strategies for MASLD with liver fibrosis, using non-invasive tests, should be applied in individuals with cardiometabolic risk factors, abnormal liver enzymes, and/or radiological signs of hepatic steatosis, particularly in the presence of type 2 diabetes (T2D) or obesity with additional metabolic risk factor(s). A stepwise approach using blood-based scores (such as FIB-4) and, sequentially, imaging techniques (such as transient elastography) is suitable to rule-out/in advanced fibrosis, which is predictive of liver-related outcomes. In adults with MASLD, lifestyle modification - including weight loss, dietary changes, physical exercise and discouraging alcohol consumption - as well as optimal management of comorbidities - including use of incretin-based therapies (e.g. semaglutide, tirzepatide) for T2D or obesity, if indicated - is advised. Bariatric surgery is also an option in individuals with MASLD and obesity. If locally approved and dependent on the label, adults with non-cirrhotic MASH and significant liver fibrosis (stage ≥2) should be considered for a MASH-targeted treatment with resmetirom, which demonstrated histological effectiveness on steatohepatitis and fibrosis with an acceptable safety and tolerability profile. No MASH-targeted pharmacotherapy can currently be recommended for the cirrhotic stage. Management of MASH-related cirrhosis includes adaptations of metabolic drugs, nutritional counselling, surveillance for portal hypertension and HCC, as well as liver transplantation in decompensated cirrhosis.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed non-alcoholic fatty liver disease (NAFLD), is defined as steatotic liver disease (SLD) in the presence of one or more cardiometabolic risk factor(s) and the absence of harmful alcohol intake. The spectrum of MASLD includes steatosis, metabolic dysfunction-associated steatohepatitis (MASH, previously NASH), fibrosis, cirrhosis and MASH-related hepatocellular carcinoma (HCC). This joint EASL-EASD-EASO guideline provides an update on definitions, prevention, screening, diagnosis and treatment for MASLD. Case-finding strategies for MASLD with liver fibrosis, using non-invasive tests, should be applied in individuals with cardiometabolic risk factors, abnormal liver enzymes, and/or radiological signs of hepatic steatosis, particularly in the presence of type 2 diabetes (T2D) or obesity with additional metabolic risk factor(s). A stepwise approach using blood-based scores (such as FIB-4) and, sequentially, imaging techniques (such as transient elastography) is suitable to rule-out/in advanced fibrosis, which is predictive of liver-related outcomes. In adults with MASLD, lifestyle modification - including weight loss, dietary changes, physical exercise and discouraging alcohol consumption - as well as optimal management of comorbidities - including use of incretin-based therapies (e.g. semaglutide, tirzepatide) for T2D or obesity, if indicated - is advised. Bariatric surgery is also an option in individuals with MASLD and obesity. If locally approved and dependent on the label, adults with non-cirrhotic MASH and significant liver fibrosis (stage ≥2) should be considered for a MASH-targeted treatment with resmetirom, which demonstrated histological effectiveness on steatohepatitis and fibrosis with an acceptable safety and tolerability profile. No MASH-targeted pharmacotherapy can currently be recommended for the cirrhotic stage. Management of MASH-related cirrhosis includes adaptations of metabolic drugs, nutritional counselling, surveillance for portal hypertension and HCC, as well as liver transplantation in decompensated cirrhosis.

The result of ongoing liver injury - and disease, regardless of cause - is fibrosis, and fibrosis appears to be a critically important result of ongoing injury. Further, in a number of different liver diseases, the presence of fibrosis has prognostic value. Therefore, the assessment of fibrosis is of critical clinical importance. Given the importance of fibrosis, there has been a rapid evolution in the use of noninvasive liver tests. This review highlights a number of the core principles surrounding.

The use of noninvasive test has progressed rapidly over the last decade and data are rapidly accumulating. New terminology has been adapted by the American Association for the Study of Liver Disease (AASLD) for noninvasive assessment of liver disease and termed 'NILDA' (Non-Invasive Liver Disease Assessment). Blood based such as APRI and or FIB-4 and imaging tests such as liver stiffness measurement (LSM) have moderate to high degrees of accuracy for detection of advanced liver fibrosis (≥ F2) and even higher accuracy for detection of severe fibrosis (F4 or cirrhosis). NILDA are particularly effective at the ends of the liver disease spectrum. For example, a very low LSM (less than 7 kPa) essentially excludes significant fibrosis or portal hypertension, and a very high LSM (> 25 kPa) makes significant fibrosis with portal hypertension (cirrhosis) highly likely.

NILDA are currently front and center in terms of assessment of the severity of liver disease. In all patients with known or suspected liver disease, noninvasive blood tests, including APRI and or FIB-4, should be the initial choice to assess the severity of liver fibrosis and/or portal hypertension. In most patients, these tests should be followed with imaging evaluation. The most commonly available imaging is LSM, which appears to be more accurate in predicting fibrosis severity, and is superior to blood tests in the assessment of portal hypertension. In situations in which there is diagnostic uncertainly, liver biopsy with or without HVPG remains an important consideration.

The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update Expert Review is to provide clinicians with guidance on the use of noninvasive tests (NITs) in the evaluation and management of patients with nonalcoholic fatty liver disease (NAFLD). NAFLD affects nearly 30% of the global population and is a growing cause of end-stage liver disease and liver-related health care resource utilization. However, only a minority of all patients with NAFLD experience a liver-related outcome. It is therefore critically important for clinicians to assess prognosis and identify those with increased risk of disease progression and negative clinical outcomes at the time of initial assessment. It is equally important to assess disease trajectory over time, particularly in response to currently available therapeutic approaches. The reference standard for assessment of prognosis and disease monitoring is histologic examination of liver biopsy specimens. There are, however, many limitations of liver biopsies and their reading that have limited their use in routine practice. The utilization of NITs facilitates risk stratification of patients and longitudinal assessment of disease progression for patients with NAFLD. This clinical update provides best practice advice based on a review of the literature on the utilization of NITs in the management of NAFLD for clinicians. Accordingly, a combination of available evidence and consensus-based expert opinion, without formal rating of the strength and quality of the evidence, was used to develop these best practice advice statements.

This Expert Review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. These best practice advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these best practice advice statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. Best Practice Advice Statements BEST PRACTICE ADVICE 1: NITs can be used for risk stratification in the diagnostic evaluation of patients with NAFLD. BEST PRACTICE ADVICE 2: A Fibrosis 4 Index score <1.3 is associated with strong negative predictive value for advanced hepatic fibrosis and may be useful for exclusion of advanced hepatic fibrosis in patients with NAFLD. BEST PRACTICE ADVICE 3: A combination of 2 or more NITs combining serum biomarkers and/or imaging-based biomarkers is preferred for staging and risk stratification of patients with NAFLD whose Fibrosis 4 Index score is >1.3. BEST PRACTICE ADVICE 4: Use of NITs in accordance with manufacturer's specifications (eg, not in patients with ascites or pacemakers) can minimize risk of discordant results and adverse events. BEST PRACTICE ADVICE 5: NITs should be interpreted with context and consideration of pertinent clinical data (eg, physical examination, biochemical, radiographic, and endoscopic) to optimize positive predictive value in the identification of patients with advanced fibrosis. BEST PRACTICE ADVICE 6: Liver biopsy should be considered for patients with NIT results that are indeterminate or discordant; conflict with other clinical, laboratory, or radiologic findings; or when alternative etiologies for liver disease are suspected. BEST PRACTICE ADVICE 7: Serial longitudinal monitoring using NITs for assessment of disease progression or regression may inform clinical management (ie, response to lifestyle modification or therapeutic intervention). BEST PRACTICE ADVICE 8: Patients with NAFLD and NITs results suggestive of advanced fibrosis (F3) or cirrhosis (F4) should be considered for surveillance of liver complications (eg, hepatocellular carcinoma screening and variceal screening per Baveno criteria). Patients with NAFLD and NITs suggestive of advanced hepatic fibrosis (F3) or (F4), should be monitored with serial liver stiffness measurement; vibration controlled transient elastography; or magnetic resonance elastography, given its correlation with clinically significant portal hypertension and clinical decompensation.

Recent progress in our understanding of the pathogenic mechanisms that drive progression of nonalcoholic steatohepatitis as well as lessons learned from several clinical trials that have been conducted over the past 15 years guide our current regulatory framework and trial design. Targeting the metabolic drivers should probably be the backbone of therapy in most of the patients, with some requiring more specific intrahepatic antiinflammatory and antifibrotic actions to achieve success. New and innovative targets and approaches as well as combination therapies are currently explored, while awaiting a better understanding of disease heterogeneity that should allow for future individualized medicine.

Fatty liver disease and fibrosis are common in patients with type 2 diabetes mellitus (T2DM). Recently published European Association for the Study of the Liver guidelines have suggested screening such patients using liver stiffness measurement (LSM) or fibrosis-4 index (FIB-4) to exclude advanced fibrosis.

We initiated a screening programme at the diabetes out-patient clinic to assess the reliability of the suggested approaches and resulting referrals.

In this prospective study, consecutive patients attending for T2DM review at an Irish level 3 (district general) hospital between September and November 2021 were screened for liver fibrosis using LSM and had their FIB-4 calculated. The first 100 patients with valid LSM measurements were included in the analysis.

Referral rates to the hepatology clinic varied by modality used. If FIB-4 ≥ 1.3 criterion was used, the referral rate to the hepatology clinic was 45%; using LSM < 8 kPa to rule out advanced fibrosis resulted in 34% referral rate; using LSM ≥ 10 kPa to suggest probable compensated advanced chronic liver disease reduced referral rates to 15%. Combining FIB-4 with LSM in a two-step algorithm led to missed potentially significant liver disease in large numbers. 47% patients with LSM ≥ 8 kPa and 33% with LSM ≥ 10 kPa had FIB-4 < 1.3.

Screening of patients with T2DM using LSM alone rather than FIB-4 leads to reduced numbers of, and more appropriate, referrals to the hepatology clinic. Shifting from an exclusion (LSM < 8 kPa) to an inclusion based (LSM ≥ 10 kPa) approach may lessen the potential of screening to overwhelm hepatology services.

Vibration-controlled transient elastography (VCTE) is a noninvasive tool that uses liver stiffness measurement (LSM) to assess fibrosis. Since real-life data during everyday clinical practice in the USA are lacking, we describe the patterns of use and diagnostic performance of VCTE in patients at an academic medical center in New York City.

Patients who received VCTE scans were included if liver biopsy was performed within 1 year. Diagnostic performance of VCTE in differentiating dichotomized fibrosis stages was assessed via area under the receiver operating characteristics (AUROC). Fibrosis stage determined from VCTE LSM was compared to liver biopsy.

Of 109 patients, 49 had nonalcoholic fatty liver disease, 16 chronic hepatitis C, 15 congestive hepatopathy, and 22 at least two etiologies. AUROC was 0.90 for differentiating cirrhosis (stage 4) with a positive predictive value (PPV) range of 0.28 to 0.45 and negative predictive value range of 0.96 to 0.98. For 31 (32%) patients, VCTE fibrosis stage was at least two stages higher than liver biopsy fibrosis stage. Thirteen of thirty-five patients considered to have cirrhosis by VCTE had stage 0 to 2 and 12 stage 3 fibrosis on liver biopsy.

VCTE has reasonable diagnostic accuracy and is reliable at ruling out cirrhosis. However, because of its low PPV, caution must be exercised when used to diagnose cirrhosis, as misdiagnosis can lead to unnecessary health care interventions. In routine practice, VTCE is also sometimes performed for disease etiologies for which it has not been robustly validated.

Screening endoscopy for varices may be deferred when the calculated EVendo score is ≤3.90. This novel score has not been validated in an external cohort. This study aimed to assess the performance of the EVendo score and compare it with the Baveno VI criteria.

We identified and calculated this score in all cirrhotic patients who underwent screening endoscopy for the first time with laboratory tests and liver stiffness measurements within 6 months of the endoscopy date.

In total, 103 patients were included. An EVendo score of ≤3.90 identified patients with no gastroesophageal varices (GEV) and varices needing treatment (VNT) with sensitivities of 82% and 83% and specificities of 57% and 34%, respectively. The negative predictive value for VNT was 94%. A comparison with the Baveno VI criteria in Child-Turcotte-Pugh-A patients showed spared endoscopy and missed VNT rates with EVendo score cutoffs of ≤3.9 and ≤4.5 and the Baveno VI criteria of 25%, 33%, and 16.6% and 1.7%, 1.7%, and 0%, respectively.

EVendo score is reliable in clinical practice for predicting GEV and VNT. The number of spared endoscopies was higher than that with the Baveno VI criteria; however, there were more missed VNT cases.

Noninvasive measures to estimate liver fibrosis in lieu of biopsy in nonalcoholic liver disease (NAFLD) can broadly differentiate high vs low degrees of condition extent. However, an "indeterminate score" necessitates further clinical investigation and biopsy becomes essential, highlighting the need for identification of other noninvasive factors with accuracy for this midlevel extent and its prognosis. Lean NAFLD cases are of particular interest regarding this issue, as they present as otherwise healthy, and will benefit greatly from the less invasive assessment.

To estimate the agreement of two noninvasive assessment tools in lean NAFLD patients, and assess factors related to indeterminate scores.

Ultrasound-diagnosed NAFLD patients, without sign of other chronic liver disease (n = 1262), were enrolled from a tertiary private medical centre between 2016-2019. After grouping by body mass index (obese, overweight, and lean), each participant underwent FibroScan. NAFLD fibrosis score (NFS) was used for subclassification (lower, higher, and indeterminate). No patient underwent liver biopsy. The kappa statistic was used to assess inter-rater agreement between the three groups on liver fibrosis degree assessed via FibroScan and NFS. Indeterminate score among the three groups was assessed to identify factors that predict its determination.

The NAFLD study cohort was composed of lean (159/1262, 12.6%), overweight (365/1262, 29%) and obese (737/1262, 58.4%) individuals. The lean patients were significantly younger (49.95 ± 15.3 years, P < 0.05), with higher serum high density lipoprotein (52.56 ± 16.27 mg/dL, P < 0.001) and lower prevalences of type 2 diabetes mellitus, hypertension and hyperlipidaemia. All groups showed a predominance of lower fibrosis degree. The lean NAFLD patients showed a significantly lower NFS (P < 0.001). Degree of agreement between FibroScan and NFS was fair between the lean and obese NAFLD categories, and moderate in the overweight category. NFS was predictive of indeterminate score. Age was a factor among all the body mass index (BMI) categories; other associated factors, but with less strength, were serum alanine aminotransferase in the overweight category and BMI in the obese category.

Lean NAFLD patients showed lower degree and prevalence of liver fibrosis by NFS; however, follow-up biopsy is still needed.

Recently, Papatheodoridi et al proposed to refine the Baveno VI elastography dual-cutoffs and introduce an algorithm for the detection of compensated advanced chronic liver disease (cACLD) in asymptomatic European patients with chronic liver diseases.

To validate the performance of the dual-cutoffs (8/12 kPa) and the proposed algorithm to identify patients with cACLD in three well-characterised Asian nonalcoholic fatty liver disease (NAFLD) cohorts.

We included 830 patients with biopsy-proven NAFLD. Liver stiffness was measured using transient elastography (FibroScan).

cACLD was found in 21.8% of patients. Compared with the original Baveno VI elastography criteria (10/15 kPa), the new cutoffs showed a comparable specificity and a higher sensitivity for identifying cACLD. We developed a simplified risk model incorporating age, liver stiffness value, and platelet count, which outperformed liver stiffness measurement alone in two Chinese cohorts (P = 0.001), and was further validated in a Malaysian cohort (P = 0.04). Overall, the "two-step" screening of cACLD improved classification rates from 73.5% by the original dual-cutoffs to 86.7%. Notably, usage of our simplified risk model resulted in significantly lower false-negative rate than the refined screening approach by Papatheodoridi et al (27.1% vs 41.4%; P = 0.01).

The dual elastography cutoffs of 8 and 12 kPa are more appropriate to identify cACLD in Asian patients with NAFLD. In combination with a simplified risk model in unclassified patients, the two-step approach showed a classification rate of about 85%.

To compare the evaluation of various non-invasive examination include ultrasound, fibroscan and computed tomography (CT) in normal alanine aminotransferase (ALT) non-obese patients, to analyse the consistency and advantages among these non-invasive examination in non-alcoholic fatty liver disease (NAFLD) patients.

About 322 cases of non-obese NAFLD patients (BMI < 25 kg/m2 ) with normal ALT were enroled. All patients were diagnosed with fatty liver by abdominal ultrasonography. Meanwhile, computed tomography and fibroscan were used to evaluate the existence and severity of fatty liver.

A 47.52% and 67.70% patients who diagnosed as NAFLD by ultrasound were unable to be diagnosed with fatty liver in accordance with the standard of controlled attenuation parameter (CAP) value by fibroscan and liver/spleen density ratio (L/S ratio) by CT. The evaluation of NAFLD by CAP standard were influenced by several factors, while only age and Triglyceride (TG) may affect the judgement of fatty liver when CT was used. Liver stiffness measurement (LSM) affects the diagnostic coincidence rate of fibroscan, CT and ultrasound. Statistical difference could be found among different LSM groups in the severity of NAFLD evaluated by Fibroscan and CT.

There is a discrepancy in the evaluation NAFLD by fibroscan, CT and ultrasound. LSM may affect the diagnostic coincidence rate of fibroscan, CT and ultrasound. Non-invasive assessment model including multiple clinical data and image results should be investigated in evaluating the degree of NAFLD. Interpretation of the diagnostic results about fibroscan, CT and ultrasound in the evaluation of NAFLD should take into account the specific clinical data of each patient.

In the past decade, numerous studies have evaluated the roles of noninvasive methods for diagnosing or excluding varices and high-risk varices in patients with liver cirrhosis. The Baveno VI criteria recommend the use of a simple algorithm based on a liver stiffness measurement < 20 kPa through transient elastography and a platelet count > 150 × 10⁹/L for ruling out high-risk varices in patients with compensated advanced chronic liver disease. A large number of studies have validated the clinical usefulness of Baveno VI criteria for excluding high-risk varices. Several strategies have been proposed to refine the Baveno VI criteria; however, currently there is no review to summarize the diagnostic accuracy and limitations of the Baveno VI criteria after extensive validation. In this review, we summarize the diagnostic accuracy and limitations of the Baveno VI criteria after extensive validation. We also discuss methods to refine these criteria.

Type 2 diabetes is an important risk factor for nonalcoholic fatty liver disease (NAFLD) and advanced fibrosis. Current international guidelines recommend the use of noninvasive tests as initial assessments for NAFLD, but the role of noninvasive tests as monitoring tools has not been established. We aimed to study the role of transient elastography as a monitoring tool in patients with type 2 diabetes.

We recruited patients with type 2 diabetes without viral hepatitis or excessive alcohol intake from a complication screening facility in Hong Kong in 2013-2014 and repeated the assessments in 2016-2018. The primary endpoint was an increase of liver stiffness measurement (LSM) to ≥10 kPa. The secondary endpoint was the change in the controlled attenuation parameter (CAP). A total of 611 patients with type 2 diabetes and a valid LSM (mean age, 57.7 ± 10.9 years; 342 men [56.0%]) were included in this study (568 also had a valid CAP). Overall, there was moderate correlation between the baseline and follow-up LSM (r = 0.689, P < 0.001). Among 487 patients with a baseline LSM <10 kPa, 21 (4.3%) had a follow-up LSM ≥10 kPa. Baseline body mass index, alanine aminotransferase (ALT), and ∆ALT were independent factors associated with LSM increase. Among 124 patients with a baseline LSM ≥10 kPa, 70 (56.5%) had a follow-up LSM <10 kPa. Among 198 patients with a CAP <248 dB/m at baseline, 103 (52.0%) had a CAP increased to ≥248 dB/m.

The prevalence and incidence of NAFLD in patients with type 2 diabetes are high. Although advanced fibrosis is common in this population, few patients progress to advanced fibrosis in 3 years. Future studies should define the optimal surveillance interval in patients with diabetes.

The association between Liver fibrosis (LF), as assessed by either histology or Liver stiffness measurement (LSM), and the presence of Early kidney dysfunction (EKD) was investigated in this study, as was also the diagnostic performance of LSM for identifying the presence of EKD in patients with Non-alcoholic fatty liver disease (NAFLD).

A total of 214 adults with non-cirrhotic biopsy-proven NAFLD were recruited from two independent medical centres. Their histological stage of LF was quantified using Brunt's criteria. Vibration-controlled Transient elastography (TE), using M-probe (FibroScan®) ultrasound, was performed in 154 patients and defined as significant when LSM was≥8.0kPa. EKD was defined as the presence of microalbuminuria with an estimated glomerular filtration rate≥60mL/min/1.73 m2. Logistic regression modelling was used to estimate the likelihood of having EKD with NAFLD (LSM-EKD model).

The prevalence of EKD was higher in patients with vs without LF on histology (22.14% vs 4.82%, respectively; P<0.001) and, similarly, EKD prevalence was higher in patients with LSM≥8.0kPa vs LSM<8.0kPa (23.81% vs 6.59%, respectively; P<0.05). The area under the ROC curve of the LSM-EKD model for identifying EKD was 0.80 (95% CI: 0.72-0.89). LF detected by either method was associated with EKD independently of established renal risk factors and potential confounders.

LF was independently associated with EKD in patients with biopsy-proven NAFLD. Thus, TE-measured LSM, a widely used technique for quantifying LF, can accurately identify those patients with NAFLD who are at risk of having EKD.

Repeating liver stiffness measurement (LSM) was recently reported to improve accuracy to diagnose fibrosis stage in patients with non-alcoholic fatty liver disease (NAFLD). There are to date no other studies confirming this finding. This aims to evaluate the accuracy of repeating LSM for the diagnosis of fibrosis stage in NAFLD patients.

Retrospective analysis of prospectively collected data on adult NAFLD patients who had two FibroScan examination within 6 months prior to liver biopsy. F3-F4 fibrosis was excluded using LSM cut-off of 7.9 kPa.

A total of 136 patients were recruited. Eighty-five percent (115/136) of patients had high baseline LSM (≥ 7.9 kPa). Among them, 25% (29/115) had low repeat LSM (< 7.9 kPa), with only two patients having F3 fibrosis. Forty-eight percent (41/86) of patients with high baseline and repeat LSMs had greater than or equal to F3-F4 fibrosis. All 21 patients with low baseline LSM had F0-F2 fibrosis, except one patient with high repeat LSM who had F3 fibrosis. A strategy of repeating LSM, where only patients with high LSM on both baseline and repeat scans are considered for liver biopsy, will be able to reduce the number of patients being considered for liver biopsy from 85% to 63%. The sensitivity, specificity, positive predictive value, and negative predictive value based on only the baseline scan was 98%, 22%, 37%, and 95%, respectively, while based on the strategy of repeating LSM was 93%, 51%, 48%, and 94%, respectively.

False positive diagnosis of advanced fibrosis in NAFLD patients can be reduced, and unnecessary liver biopsy can be avoided by repeating LSM.

Liver fibrosis should be assessed in all individuals with chronic liver disease as it predicts the risk of future liver-related morbidity and thus need for treatment, monitoring and surveillance. Non-invasive fibrosis tests (NITs) overcome many limitations of liver biopsy and are now routinely incorporated into specialist clinical practice. Simple serum-based tests (eg, Fibrosis Score 4, non-alcoholic fatty liver disease Fibrosis Score) consist of readily available biochemical surrogates and clinical risk factors for liver fibrosis (eg, age and sex). These have been extensively validated across a spectrum of chronic liver diseases, however, tend to be less accurate than more 'complex' serum tests, which incorporate direct measures of fibrogenesis or fibrolysis (eg, hyaluronic acid, N-terminal propeptide of type three collagen). Elastography methods quantify liver stiffness as a marker of fibrosis and are more accurate than simple serum NITs, however, suffer increasing rates of unreliability with increasing obesity. MR elastography appears more accurate than sonographic elastography and is not significantly impacted by obesity but is costly with limited availability. NITs are valuable for excluding advanced fibrosis or cirrhosis, however, are not sufficiently predictive when used in isolation. Combining serum and elastography techniques increases diagnostic accuracy and can be used as screening and confirmatory tests, respectively. Unfortunately, NITs have not yet been demonstrated to accurately reflect fibrosis change in response to treatment, limiting their role in disease monitoring. However, recent studies have demonstrated lipidomic, proteomic and gut microbiome profiles as well as microRNA signatures to be promising techniques for fibrosis assessment in the future.

Liver stiffness measurement (LSM) by FibroScan-determined transient elastography is a noninvasive approach to estimate liver fibrosis severity. In non-alcoholic fatty liver disease (NAFLD), advanced liver fibrosis is excluded by normal liver stiffness, but a wide range of cutoffs have been used to predict advanced liver fibrosis or cirrhosis. This may be partly because steatosis (measured by controlled attenuation parameter [CAP]) contributes to liver stiffness and also because LSM fluctuates in NAFLD. In a recent pivotal study, one-third of patients with liver stiffness > 12.0 kPa showed reversal after 4-6 months; these cases did not have advanced liver fibrosis on biopsy. We performed serial FibroScans 6-36 months apart in 73 NAFLD patients, 38 with LSM > 10 kPa at entry. Those who lost ≥ 1 kg of weight (n = 31) significantly reduced liver stiffness (3.6 ± 6.1 vs 0.53 ± 4.1 kPa, P < 0.05) and CAP score (39 ± 63 dB/m of loss vs 24 ± 65 dB/m of gain, P < 0.05) compared with those who did not (n = 29). Patients who reported increased physical activity (n = 25) also reduced liver stiffness (3.6 ± 6 vs 0.35 ± 6 kPa) and CAP (20 ± 71 dB/m of loss vs 32 ± 71 dB/m of gain). Overall, those with improved LSM were significantly more likely to have lost weight and/or improved physical activity. These effects of lifestyle adjustments partly explain why a single measurement of 12.0 kPa is not a reliable cutoff for advanced liver fibrosis in NAFLD. In addition to repeating the study after 6-12 months, documentation of response to lifestyle advice and weight reduction should be determined before assuming any cutoff indicates advanced liver fibrosis. Despite this reservation about diagnostic accuracy, we consider that measurement of liver stiffness and CAP score serve to motivate patients to enact lifestyle modifications that can improve NAFLD severity.

The global problems of chronic liver disease and non-alcoholic fatty liver disease (NAFLD) are increasing. We examined the prevalence of NAFLD and significant liver stiffness in an asymptomatic population and identified the predictors of significant fibrosis in NAFLD.

We prospectively enrolled Thai subjects, aged 18-80 years, from four regions (Bangkok, Central, North, South) of Thailand from March 2013 to November 2016. All participants underwent controlled attenuation parameter (CAP) measurement for liver fat quantification and transient elastography (TE) for liver stiffness measurement (LSM). NAFLD was defined as liver fat ≥10% (CAP ≥ 306 dB/m). Of 1145 participants, 782 (68.3%) were eligible for analysis.

The mean age ± standard deviation (SD) was 53.1 ± 4.6 years, and 71.6% were female. The mean ± SD values of CAP and LSM of the overall cohort were 241.9 ± 61.4 dB/m and 5.5 ± 3.8 kPa, respectively. The prevalence of NAFLD was 18.0%, whereas 5.4% of the cohort had nonobese NAFLD (BMI < 25 kg/m2), and 2.8% had lean NAFLD (BMI < 23 kg/m2). The prevalence of significant liver fibrosis (≥F2) in NAFLD subjects was 18.4%. On multivariate analysis, the degree of significant fibrosis in NAFLD was significantly associated with male gender and a history of dyslipidemia.

NAFLD with significant fibrosis (≥F2) is prevalent in asymptomatic populations. The predictors of significant fibrosis in NAFLD were male gender and dyslipidemia. Screening for NAFLD using CAP/TE in asymptomatic populations should be considered in hospitals with available facilities.

With rapid lifestyle transitions, the increasing burden of nonalcoholic fatty liver disease (NAFLD) in China has emerged as a major public health issue. To obtain a comprehensive overview of the status of NAFLD over the past decade, we evaluated the epidemiology, risk factors, complications, and management of NAFLD in China through a systematic review and meta-analysis. Five English literature databases and three Chinese databases were searched for relevant topics from 2008 to 2018. A total of 392 studies with a population of 2,054,554 were included. National prevalence of NAFLD was 29.2%, with a heavier disease burden among the middle-aged, males, those in northwest China and Taiwan, regions with a gross domestic product per capita greater than 100,000 yuan, and Uygur and Hui ethnic groups. Currently, original studies on natural history and complications of NAFLD in China are scarce. Several studies revealed that NAFLD is positively correlated with the incidence of extrahepatic tumors, diabetes, cardiovascular disease and metabolic syndrome. The Chinese population may have a higher hereditary risk of NAFLD due to more frequent nonsynonymous mutations in genes regulating lipid metabolism. Ultrasonography is the primary imaging tool in the detection of NAFLD in China. Serum tests and risk stratification algorithms for staging NAFLD remain under investigation. Specific pharmaceutical treatments for NAFLD are still undergoing clinical trials. It is noteworthy that the Chinese are underrepresented compared with their proportion of the NAFLD population in such trials. Conclusion: China experienced an unexpected rapid increase in the burden of NAFLD over a short period. Rising awareness and urgent actions need to be taken in order to control the NAFLD pandemic in China.

Although liver biopsy is the gold standard for the diagnosis and staging of non-alcoholic fatty liver disease (NAFLD), repeated assessment of patients' liver tissue conditions are impractical. We assessed the 10-year changes in liver stiffness measurements (LSM) utilizing vibration-controlled transient elastography in NAFLD patients.

From January 2006 to September 2007, LSM was carried out for 97 biopsy-proven NAFLD patients. Of these, 34 patients underwent 10-year LSM reassessments (14 of them with paired biopsies).

We evaluated the changes in the fibrosis stage as estimated using LSM (FS-LSM). Over a 10-year period, 32.4% had FS-LSM progression, 50% had static disease, and 17.6% had FS-LSM improvement. From among the initially diagnosed non-alcoholic steatohepatitis patients, 18% had progressed to considerable stage 4 (cirrhosis) 10 years later. In this cohort, none of the patients who had been initially diagnosed as FS-LSM stage 0 had progressed to cirrhosis 10 years later. The changes in LSM were correlated with the change in the histological fibrosis stage, the NAFLD activity score, and the change in the sum of the steatosis, activity, and fibrosis score. Improving more than 1 body mass index (kg/m² ) and having a higher initial aspartate aminotransferase, alanine aminotransferase (ALT), or ALT responder (>30% improvement or reduction to less than 40 IU/L) were factors contributing to LSM improvements (≥2 kPa).

Vibration-controlled transient elastography is likely to become a more clinically important tool for the long-term monitoring of NAFLD patients.

Introduction: Nonalcoholic fatty liver disease (NAFLD) spans steatosis through nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). NAFLD carries an increased risk of cardio-metabolic and liver-related events accounting for a substantial economic burden. Given that the natural history of NAFLD is critically dependent on the stage of fibrosis, non-invasively identifying the subgroup of patients at a higher risk of progressive disease is key. Areas covered: This review highlights the recent developments in the use of ultrasound-based techniques in NAFLD and their performance in predicting metabolic derangements, cardiovascular risk, and progression of liver disease, notably including diagnosis of fibrosing NASH, identification, and treatment of HCC. Expert opinion: Our ability to identify NAFLD patients and to estimate steatofibrosis with various ultrasound-based techniques has undergone tremendous progress over the last few years. However, it is more difficult to capture the inflammatory component of NASH with such ultrasound-assisted techniques. Moreover, semi-quantitative, quantitative, elastographic, and contrast-enhanced ultrasound techniques are increasingly being appreciated and made available but not all such techniques will gain success in the clinical and research area. Therefore, further research will precisely define the role of the most innovative ultrasonographic techniques, while reducing costs and increasing feasibility.