Controlled attenuation parameter for non-invasive assessment of hepatic steatosis in Chinese patients

Vibration Controlled Transient Elastography in Screening for Silent Liver Diseases

OBJECTIVES

The objective of this study was to screen for significant hepatic fibrosis or steatosis in asymptomatic, apparently healthy subjects by using Vibration-controlled transient elastography and controlled attenuation parameter (CAP).

METHODS

Prospectively, 433 asymptomatic apparently healthy adults were included. Fibroscan/CAP examination was performed for all of them. Subjects with liver stiffness measurement > 6 kPa or CAP >248 dB/m were further evaluated to assess underlying chronic liver disease.

RESULTS

According to fibroscan/CAP examination, subjects were classified into four subgroups: normal (119) with CAP score of 215.85 ± 24.81 dB/m and fibrosis score of 4.47 ± 0.81 kPa, subjects with steatosis only 133 with CAP score of 309.41 ± 42.6 dB/m and fibrosis score of 4.74 ± 0.82 kPa, subjects with both steatosis and fibrosis 95 with CAP score of 318.20 ± 39.89 dB/m and fibrosis score of 7.92 ± 2.58 kPaand subjects with fibrosis only 86 with CAP score of 213.48 ± 22.62 dB/m and fibrosis score of 6.96 ± 1.11 kPa. S0 was present in 205 (47.3%), S1 in 48 (10.2%), S2 in 16 (3.7%) and S3 in 168 (38.8%) of studied subjects, whereas F0-1 was present in 371 (85.7%), F2 in 44 (10.16%), F3 in 16 (3.7%) subjects and F4 in only one (0.23%) subject. Subjects with both steatosis and fibrosis showed significantly higher transaminases, triglycerides and total cholesterol levels than other subgroups.

CONCLUSIONS

Most asymptomatic, apparently healthy subjects (72%) have significant steatosis and fibrosis. Liver stiffness measurement and CAP might represent promising first-line noninvasive procedures to screen for silent liver diseases in the general population.

Efficacy of curcumin plus piperine co-supplementation in moderate-to-high hepatic steatosis: A double-blind, randomized, placebo-controlled clinical trial

Non-alcoholic Fatty Liver Disease (NAFLD) is a global health problem that can progress to steatohepatitis and cirrhosis. The aim of this study was to determine the effect of curcumin + piperine on cardiometabolic risk factors, as well as hepatic steatosis and fibrosis in NAFLD patients with moderate-to-high hepatic steatosis. Patients diagnosed with moderate-to-high NAFLD by liver sonography were randomized to either curcumin + piperine (500 mg/day curcumin plus 5 mg/day piperine) for 12 weeks (n = 30) or placebo groups (n = 30). Liver fibroscan, anthropometric measurements, dietary intake, physical activity, blood pressure, lipid profile, high-sensitivity C-reactive protein, fasting blood glucose (FBG), and liver enzymes were assessed at baseline and after 12 weeks of follow-up. Intention-to-treat analysis was undertaken. Curcumin + piperine decreased waist circumference (p = 0.026), systolic blood pressure (p = 0.001), total cholesterol (p = 0.004), low-density lipoprotein-cholesterol (p = 0.006), FBG (p = 0.002), alanine transaminase (p = 0.007) and aspartate transaminase (p = 0.012) compared with placebo. However, fibroscan measurement did not differ between curcumin + piperine and placebo groups (p > 0.05). Fibroscan measurement as a marker of NAFLD improvement did not differ after 12 weeks of curcumin + piperine; however, curcumin + piperine may be considered as an adjunct therapy to improve anthropometric measures, blood pressure, lipid profile, blood glucose, and liver function in NAFLD patients.

The diagnostic value of novel ultrasound attenuation analysis in detecting liver steatosis identified by the controlled attenuation parameter: a diagnostic accuracy study

Background

Ultrasound attenuation analysis (USAT) is a type of novel ultrasound attenuation imaging that can be used to detect hepatic steatosis based on the attenuation coefficient. We sought to evaluate the diagnostic accuracy for assessing the severity of liver steatosis by USAT using the controlled attenuation parameter (CAP) as a reference in patients with non-alcoholic fatty liver diseases (NAFLD) and chronic hepatitis B (CHB) infections.

Methods

In total, 326 consecutive subjects with or without chronic liver diseases were enrolled in this study who underwent CAP examination and USAT to evaluate hepatic steatosis from October 2022 to November 2022 at The Fourth Affiliated Hospital of Zhejiang University School of Medicine. Hepatic steatosis stage (S) was determined by CAP according to the following cut-off values recommended by the manufacturer: S ≥ S1 (≥11%, mild): 238 dB/m; S ≥ S2 (≥34%, moderate): 259 dB/m; and S ≥ S3 (≥67%, severe): 292 dB/m, and thus the optimal cut-off values for the USAT were acquired. The area under the receiver operating characteristic curves (AUROCs) for the categories of steatosis were used to measure the diagnostic accuracy of USAT.

Results

A total of 296 patients were recruited, including 101 (34.1%) patients with NAFLD, 172 (58.1%) with CHB and the remainder were healthy control subjects (7.8%). We used the CAP as the reference standard and found that the USAT increased gradually as the stage of steatosis increased (P<0.001). A strong positive correlation was found between USAT and CAP (r=0.787, P<0.001). In the whole population, the AUROCs of the USAT for S ≥ S1, S ≥ S2 and S ≥ 3 were 0.89, 0.90, and 0.90, respectively, and the cut-off values according to the Youden index for S ≥ S1, S ≥ S2, and S ≥ 3 were 0.62, 0.66, and 0.72 dB/cm/MHz, respectively. Our study showed that the USAT had a good ability to detect hepatic steatosis in NAFLD and CHB patients.

Conclusions

USAT had a strong association with CAP and a good diagnostic capability in the detection of hepatic steatosis, which appears to be a promising tool for the non-invasive detection and quantification of hepatic steatosis.

Modifications decrease hepatic steatosis in Taiwanese with metabolic-associated fatty liver disease

Metabolic-associated fatty liver disease (MAFLD) is a growing global problem associated with increasing obesity prevalence. Lifestyle modifications are currently recommended, including weight reduction, exercise, and diet control. This study evaluated the short-term effect of lifestyle modifications on transient elastography (TE) values in an obese population with MAFLD. Thirty-two MAFLD patients were recruited for this prospective study and all subjects participated in a 3-month program of lifestyle modification. Sequential demographic parameters and biochemical tests were compared before and after program completion. Liver fat and fibrosis changes were measured using TE with controlled attenuated parameter (CAP) and liver stiffness measurements (LSM). The mean age was 38.7 years old (10 males). The body weight (88.09 kg vs. 80.35 kg), body mass index (32.24 kg/m² vs. 29.4 kg/m² ), waist (103.19 cm vs. 95.75 cm), and hip circumference (111.67 cm vs. 104.75 cm), and blood pressure (128/78 mmHg vs. 119/71 mmHg) significantly improved before and after the intervention, respectively. Aspartate aminotransaminase (24.06 U/L vs. 18.91 U/L), alanine aminotransaminase (33 U/L vs. 23.72 U/L), creatinine (0.75 mg/dl vs. 0.70 mg/dl), cholesterol (176.41 mg/dl vs. 166.22 m/dl), gamma-glutamyl transferase (26.59 IU/L vs. 19.81 IU/L), and low-density lipoprotein cholesterol (115.63 mg/dl vs. 103.19 mg/dl) also improved after the 3-month intervention. The average CAP significantly decreased after intervention (297.5 dB/m vs. 255.0 dB/m), however, no significant difference in LSM was observed (5.24 kPa vs. 4.82 kPa). The current study suggests that short-term lifestyle modification can effectively improve hepatic steatosis, and TE may serve as a monitoring tool for therapeutic intervention.

Efficacy and safety of Jian-Pi Huo-Xue granule for non-alcoholic fatty liver disease: study protocol for a randomized, double-blind, placebo-controlled trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent form of chronic liver disease, with a global prevalence of 25% worldwide, but a consensus treatment is still lacking. Previous studies have shown that Jian-Pi Huo-Xue granules (JPHX) can reduce hepatic steatosis in ultrasound images, but lacked quantitative observation in imagined liver fat content. This study aimed to refine the efficacy and safety assessment of JPHX for NAFLD with magnetic resonance imaging-proton density fat fraction (MRI-PDFF) as the primary outcome.

METHODS

This is a randomized, double-blind, placebo-controlled clinical trial. The trial will enrol 84 NAFLD participants who will be equally randomized to receive either JPHX or a placebo for 24 weeks. Follow-up will be performed 12 weeks after the intervention. The primary outcome will be the change from baseline to week 24 in MRI-PDFF. Secondary outcomes will be the body weight, body mass index (BMI), waist circumference, waist-to-hip ratio (WHR), serum liver function, blood lipids and glucose-related indicators, quality of life measurement health survey, and traditional Chinese medicine (TCM) syndrome scale. Outcomes will be monitored at baseline, 12 weeks and 24 weeks after enrolment. Adverse events occurring in this trial will be managed and recorded promptly.

DISCUSSION

We designed a clinical trial for the treatment of NAFLD using JPHX, a TCM formulation that has been shown to have a positive effect on hepatic steatosis in a previous self-controlled trial. This trial will use a more recognized and quantitative imaging approach to demonstrate the efficacy of JPHX in the treatment of NAFLD and observe its safety to provide clinical evidence for its translational applications.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100046132 . Registered on 4 May 2021.

Effects of probiotics combined with dietary and lifestyle modification on clinical, biochemical, and radiological parameters in obese children with nonalcoholic fatty liver disease/nonalcoholic steatohepatitis: a randomized clinical trial

BACKGROUND

Childhood obesity is a global problem associated with metabolic abnormalities. The gut-liver axis is thought to play a major role in its pathogenesis. Probiotics are known to alter the gut microbiota and, therefore, could be a therapeutic option in the management of childhood obesity-related complications.

PURPOSE

This double-blind randomized placebo-controlled trial evaluated the effects of probiotics on metabolic derangement in obese children with nonalcoholic fatty liver disease/ nonalcoholic steatohepatitis (NAFLD/NASH).

METHODS

Obese children with NAFLD/NASH treated at the nutrition clinic of the University Paediatric Unit at Lady Ridgeway Hospital, Colombo, were recruited. Anthropometry, body fat, metabolic derangement, and liver ultrasound scan (USS) results were evaluated at baseline and after 6 months. Transient elastography (FibroScan) was performed on a subsample of these patients. Eighty-four patients were recruited and randomized into the probiotics (n=43) and placebo (n= 41) groups. The mean age was 11.3±1.9 versus 12.1±1.5 years in the probiotic and placebo groups, respectively. Baseline parameters including liver disease stage on USS, body fat percentage, fasting blood sugar, lipid profile, liver function, and C-reactive protein showed no significant intergroup differences.

RESULTS

In the probiotic group, a statistically significant reduction in body mass index was noted from the baseline value. However, the reduction was not significant compared with the placebo group. There was a significant reduction in triglycerides, aspartate transaminase (AST), alanine aminotransferase (ALT), AST/ALT ratio, and alkaline phosphatase in the placebo group over the treatment period. Although the liver disease stage on USS improved from stage II-III to stage I in a small number of patients in the probiotic-treated group, transient elastography performed in a subsample did not demonstrate significant improvement in either group.

CONCLUSION

Our results indicate that probiotics have no advantage over lifestyle modification for improving obesityassociated metabolic derangement in children.

Quantitative Evaluation of Hepatic Steatosis Using Advanced Imaging Techniques: Focusing on New Quantitative Ultrasound Techniques

Nonalcoholic fatty liver disease, characterized by excessive accumulation of fat in the liver, is the most common chronic liver disease worldwide. The current standard for the detection of hepatic steatosis is liver biopsy; however, it is limited by invasiveness and sampling errors. Accordingly, MR spectroscopy and proton density fat fraction obtained with MRI have been accepted as non-invasive modalities for quantifying hepatic steatosis. Recently, various quantitative ultrasonography techniques have been developed and validated for the quantification of hepatic steatosis. These techniques measure various acoustic parameters, including attenuation coefficient, backscatter coefficient and speckle statistics, speed of sound, and shear wave elastography metrics. In this article, we introduce several representative quantitative ultrasonography techniques and their diagnostic value for the detection of hepatic steatosis.

Diagnostic Accuracy and Optimal Cut-off of Controlled Attenuation Parameter for the Detection of Hepatic Steatosis in Indian Population

BACKGROUND AND AIMS

Ultrasound of the liver is not good to pick up mild steatosis. Controlled attenuation parameter (CAP) evaluated in transient elastography (FibroScan) is widely available in India. However, data regarding the diagnostic accuracy and optimal cut-off values of CAP for diagnosing hepatic steatosis are scarce in Indian population. MRI-PDFF is an accurate technique for quantifying hepatic steatosis. Thus, this study examined the diagnostic accuracy and optimal cut-off values of CAP for diagnosing steatosis with MRI-PDFF as reference standard.

METHODS

A total of 137 adults underwent CAP and MRI-PDFF measurements prospectively. A subset of participants (n = 23) underwent liver biopsy as part of liver transplantation evaluation. The optimal cut-off values, area under the receiver operating characteristic (AUROC) curves, sensitivity, and specificity for CAP in detecting MRI-PDFF ≥5% and ≥10% were assessed.

RESULTS

The mean age and body mass index (BMI) were 44.2 ±10.4 years and 28.3 ±3.9 kg/m², respectively. The mean hepatic steatosis was 13.0 ±7.7% by MRI-PDFF and 303 ±54 dB/m by CAP. The AUROC of CAP for detecting hepatic steatosis (MRI-PDFF ≥5%) was 0.93 (95% CI, 0.88-0.98) at the cut-off of 262 dB/m, and of MRI-PDFF ≥10% was 0.89 (95% CI, 0.84-0.94) at the cut-off of 295 dB/m. The CAP of 262 dB/m had 90% sensitivity and 91% specificity for detecting MRI-PDFF ≥5%, while the CAP of 295 dB/m had 86% sensitivity and 77% specificity for detecting MRI-PDFF ≥10%.

CONCLUSIONS

The optimal cut-off of CAP for the presence of liver steatosis (MRI-PDFF ≥5%) was 262 dB/m in Indian individuals. This CAP cut-off was associated with good sensitivity and specificity to pick up mild steatosis.

Effect of a common missense variant in LIPA gene on fatty liver disease and lipid phenotype: New perspectives from a single-center observational study

Lysosomal acid lipase deficiency (LAL-D) is an autosomal recessive disease characterized by hypoalphalipoproteinemia, mixed hyperlipemia, and fatty liver (FL) due to mutations in LIPAse A, lysosomal acid type (LIPA) gene. The rs1051338 single-nucleotide polymorphism (SNP) in LIPA gene, in vitro, could adversely affect the LAL activity (LAL-A). Nonalcoholic fatty liver disease (NAFLD) is often associated with metabolic syndrome, and the diagnosis requires the exclusion of excess of alcohol intake and other causes of hepatic disease. The aim of the study was to evaluate the impact of rs1051338 rare allele on lipid phenotype, severity of FL, and LAL-A in patients suffering from dyslipidemia associated with NAFLD. We selected 74 subjects with hypoalphalipoproteinemia or mixed hyperlipemia and evaluated transaminases, liver assessment with controlled attenuation parameter (CAP), LAL-A, rs1051338 SNP genotype. The presence of rare allele caused higher levels of triglycerides and hepatic transaminase and lower levels of high-density lipoprotein cholesterol (HDL-C). Multivariate analysis highlighted independent association between rare allele and FL severity in subjects with NAFLD. The rs1051338 SNP may modulate FL severity and atherogenic dyslipidemia in patients suffering from NAFLD.

Effect of skin-capsular distance on controlled attenuation parameter for diagnosing liver steatosis in patients with nonalcoholic fatty liver disease

The effect of the skin-capsular distance (SCD) on the controlled attenuation parameter (CAP) for diagnosis of liver steatosis in patients with nonalcoholic fatty liver disease (NAFLD) remains unclear. The SCD was measured using B-mode ultrasound, and the CAP was measured using the M probe of FibroScan®. According to the indications of the M probe, 113 patients with an SCD of ≤ 25 mm were included in the present study. The association between the SCD and CAP was investigated, and the diagnostic performance of the SCD-adjusted CAP was tested. The SCD showed the most significant positive correlation with the CAP (ρ = 0.329, p < 0.001). In the multiple regression analysis, the SCD and serum albumin concentration were associated with the CAP, independent of pathological liver steatosis. According to the multivariate analysis, two different formulas were developed to obtain the adjusted CAP using the SCD and serum albumin concentration as follows: adjusted CAP (dB/m) = CAP - (5.26 × SCD) and adjusted CAP (dB/m) = CAP - (5.35 × SCD) - (25.77 × serum albumin concentration). The area under the receiver operating characteristic curve for diagnosis of a steatosis score ≥ 2 of adjusted CAP was 0.678 and 0.684 respectively, which were significantly greater than the original CAP (0.621: p = 0.030 and p = 0.024). The SCD is associated with the CAP independent of liver steatosis. Adjustment of the CAP using the SCD improves the diagnostic performance of the CAP in NAFLD.

Polycystic ovary syndrome with feasible equivalence to overweight as a risk factor for non-alcoholic fatty liver disease development and severity in Mexican population

INTRODUCTION AND OBJECTIVES

Polycystic ovary syndrome (PCOS) is the most common endocrinology disorder in women of reproductive age; these patients have a higher risk of suffering from non-alcoholic fatty liver disease (NAFLD). We determine the frequency of NAFLD in Mexican patients with PCOS and matched-controls.

PATIENTS AND METHODS

Cross-sectional study, with 98 women of 18-44 years old. Rotterdam 2003 criteria integrated PCOS diagnosis. Those with significant alcohol consumption, chronic liver disease, use of steatogenic drugs, and pharmacological PCOS treatment or fertility protocol were excluded. Controls were matched in a 1:1 ratio by age and body mass index (BMI). The presence of NAFLD was determined by transient elastography performed by a single experienced operator.

RESULTS

A total of 98 female volunteers at reproductive age were recruited. NAFLD denoted markedly higher in patients with than without PCOS at 69.3% vs. 34.6%, respectively. Compared to controls, PCOS patients had a significantly higher risk of NAFLD (OR=4.26, 95% CI 1.83-9.93). Severe steatosis was the most frequent NAFLD stage between women with PCOS and NAFLD. Patients with hyperandrogenism have a significantly higher mean CAP 277.83dB/m than controls without hyperandrogenism 191.57dB/m. NAFLD prevalence was 84.3% in PCOS patients with phenotype A, while in another phenotype, it was 41.1%.

CONCLUSIONS

PCOS is an independent risk factor for NAFLD development. NAFLD screening needs to be considered in all PCOS patients independently of BMI, except in PCOS patients without hyperandrogenism and BMI<25.

Validating controlled attenuation parameter in the assessment of hepatic steatosis in living liver donors

INTRODUCTION

Hepatic steatosis (HS) negatively impacts transplant outcomes in living liver donors. To date, liver biopsy is preferred for HS evaluation. This study aims to evaluate the measurement of controlled attenuation parameter (CAP) as a diagnostic tool of HS in living liver donors.

METHODS

Candidates recruited to this study, conducted from April 2016 to February 2020, were potential donors who had undergone transient elastography using Fibroscan® and CAP measurements at liver segments VI and VII, followed by liver biopsy. The HS grades from liver biopsy were classified as S0 (<5%), S1 (5-33%), S2 (33-66%), and S3 (>66%). For CAP, they were S0 (≤218dB/m), S1 (218-249dB/m)), S2 (250-305dB/m)), and S3 (>305dB/m)). The CAP measurements were compared with the liver biopsy results.

RESULTS

Of the 150 potential donors [male, 73.3%; mean age, 30.0±7.0 years; body mass index (BMI), 24.7±3.5kg/m2], 92 (61.3%) had no or mild HS, while 58 (38.7%) and 10% had moderate to severe HS based on CAP and liver biopsy, respectively. Subjects with moderate to severe HS per CAP were mostly males (0.014), and had higher BMI (p = .006), alanine aminotransferase (ALT) (.001), gamma-glutamyl transferase (.026), and high-density lipoprotein (.008). On multivariate analysis, high ALT (OR, 1.051; 95% CI, 1.016-1.087; p = .004) was a predictor of significant HS. The sensitivity, specificity, positive and negative predictive values of CAP to detect significant HS were 93.3%, 67.4, 24.1%, and 98.9%, respectively.

CONCLUSION

The high sensitivity and negative predictive values of CAP make it a good screening test to exclude significant HS in potential living liver donors which, in turn, can help avoid unnecessary liver biopsies.

Magnetic Resonance Spectroscopy of Hepatic Fat from Fundamental to Clinical Applications

The number of individuals suffering from fatty liver is increasing worldwide, leading to interest in the noninvasive study of liver fat. Magnetic resonance spectroscopy (MRS) is a powerful tool that allows direct quantification of metabolites in tissue or areas of interest. MRS has been applied in both research and clinical studies to assess liver fat noninvasively in vivo. MRS has also demonstrated excellent performance in liver fat assessment with high sensitivity and specificity compared to biopsy and other imaging modalities. Because of these qualities, MRS has been generally accepted as the reference standard for the noninvasive measurement of liver steatosis. MRS is an evolving technique with high potential as a diagnostic tool in the clinical setting. This review aims to provide a brief overview of the MRS principle for liver fat assessment and its application, and to summarize the current state of MRS study in comparison to other techniques.

Comparison between magnetic resonance and ultrasound-derived indicators of hepatic steatosis in a pooled NAFLD cohort

BACKGROUND & AIMS

MRI-based proton density fat fraction (PDFF) and the ultrasound-derived controlled attenuation parameter (CAP) are non-invasive techniques for quantifying liver fat, which can be used to assess steatosis in patients with non-alcoholic fatty liver disease (NAFLD). This study compared both of these techniques to histopathological graded steatosis for the assessment of fat levels in a large pooled NAFLD cohort.

METHODS

This retrospective study pooled N = 581 participants from two suspected NAFLD cohorts (mean age (SD) 56 (12.7), 60% females). Steatosis was graded according to NASH-CRN criteria. Liver fat was measured non-invasively using PDFF (with Liver MultiScan's Iterative Decomposition of water and fat with Echo Asymmetry and Least-squares estimation method, LMS-IDEAL, Perspectum, Oxford) and CAP (FibroScan, Echosens, France), and their diagnostic performances were compared.

RESULTS

LMS-IDEAL and CAP detected steatosis grade ≥ 1 with AUROCs of 1.00 (95% CI, 0.99-1.0) and 0.95 (95% CI, 0.91-0.99), respectively. LMS-IDEAL was superior to CAP for detecting steatosis grade ≥ 2 with AUROCs of 0.77 (95% CI, 0.73-0.82] and 0.60 (95% CI, 0.55-0.65), respectively. Similarly, LMS-IDEAL outperformed CAP for detecting steatosis grade ≥ 3 with AUROCs of 0.81 (95% CI, 0.76-0.87) and 0.63 (95% CI, 0.56-0.70), respectively.

CONCLUSION

LMS-IDEAL was able to diagnose individuals accurately across the spectrum of histological steatosis grades. CAP performed well in identifying individuals with lower levels of fat (steatosis grade ≥1); however, its diagnostic performance was inferior to LMS-IDEAL for higher levels of fat (steatosis grades ≥2 and ≥3).

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03551522); https://clinicaltrials.gov/ct2/show/NCT03551522. UMIN Clinical Trials Registry (UMIN000026145); https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000026145.

Performance of liver stiffness measurements obtained with FibroScan is affected by glucose metabolism in patients with nonalcoholic fatty liver disease

Background

The performance of liver stiffness measurements (LSMs) obtained using FibroScan can be affected by several factors, and cut-off values are different for fibrosis caused by various aetiologies. The study aims to evaluate the diagnostic accuracy of LSM in nonalcoholic fatty liver disease (NAFLD) patients with abnormal glucose metabolism and investigate whether the LSM value would be affected by metabolic indicators.

Methods

The study involved 91 NAFLD patients with abnormal glucose metabolism who underwent liver biopsy. The diagnostic accuracy of LSM value was evaluated by the receiver operator characteristic (ROC) curves, with the biopsy results taken as the gold standard. Multivariate linear regression and subgroup analysis were performed to determine the correlated indicators.

Results

The areas under the ROC curves (AUROCs) of LSM values for detecting fibrosis stage ≥1, 2, 3 and 4 were 0.793 (95% confidence interval [CI]: 0.695–0.871), 0.764 (95% CI: 0.663–0.846), 0.837 (95% CI: 0.744–0.906) and 0.902 (95% CI: 0.822–0.955), with cut-off values of 6.3, 7.6, 8.3 and 13.8 kPa, respectively. Multivariate linear regression demonstrated that haemoglobin A1c (HbA1c, β = 0.205, P = 0.026) and alanine aminotransferase (ALT, β = 0.192, P = 0.047) were independently associated with the LSM value after adjustment for fibrosis stage, ballooning and inflammation grade from liver biopsy. Subgroup analysis demonstrated that LSM values were slightly higher in patients with HbA1c ≥7% than in those with HbA1c < 7% and in patients with body mass index (BMI) ≥30 kg/m² than in those with BMI < 30 kg/m².

Conclusions

FibroScan was valuable for the evaluation of liver fibrosis in NAFLD patients with abnormal glucose metabolism. FibroScan is recommended to evaluate severe fibrosis, especially to exclude advanced fibrosis. Glucose metabolism state may affect LSM values.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01453-5.

Diagnostic Accuracy of FibroScan and Factors Affecting Measurements

Evaluating liver steatosis and fibrosis is important for patients with non-alcoholic fatty liver disease. Although liver biopsy and pathological assessment is the gold standard for these conditions, this technique has several disadvantages. The evaluation of steatosis and fibrosis using ultrasound B-mode imaging is qualitative and subjective. The liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) determined using FibroScan are the evidence-based non-invasive measures of liver fibrosis and steatosis, respectively. The LSM and CAP measurements are carried out simultaneously, and the median values of more than ten valid measurements are used to quantify liver fibrosis and steatosis. Here, we demonstrate that the reliability of the LSM depends on the interquartile range to median ratio (IQR/Med), but CAP values do not depend on IQR/Med. In addition, the LSM is affected by inflammation, congestion, and cholestasis in addition to fibrosis, while CAP values are affected by the body mass index in addition to steatosis. We also show that the M probe provides higher LSM values but lower CAP values than the XL probe in the same population. However, there was no statistically significant difference between the diagnostic accuracies of the two probes. These findings are important to understand the reliability of FibroScan measurements and the factors influencing measurement values for all patients.

Hepatocellular Carcinoma and Non-Alcoholic Fatty Liver Disease: A Step Forward for Better Evaluation Using Ultrasound Elastography

Simple Summary

Non-alcoholic fatty liver disease (NAFLD) attracts a lot of attention, due to the increasing prevalence and progression to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Consequently, new non-invasive, cost-effective diagnostic methods are needed. This review aims to explore the diagnostic performance of ultrasound (US) elastography in NAFLD and NAFLD-related HCC, adding a new dimension to the conventional US examination—the liver stiffness quantification. The vibration controlled transient elastography (VCTE), and 2D-Shear wave elastography (2D-SWE) are effective in staging liver fibrosis in NAFLD. VCTE presents the upside of assessing steatosis through the controlled attenuation parameter. Hereby, we critically reviewed the elastography techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography and 2D-SWE. 2D-SWE presents a great potential to differentiate malignant from benign FLLs, guiding the clinician towards the next diagnostic steps. As a disease-specific surveillance tool, US elastography presents prognostic capability, improving the NAFLD-related HCC monitoring.

Abstract

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in the general population prompts for a quick response from physicians. As NAFLD can progress to liver fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC), new non-invasive, rapid, cost-effective diagnostic methods are needed. In this review, we explore the diagnostic performance of ultrasound elastography for non-invasive assessment of NAFLD and NAFLD-related HCC. Elastography provides a new dimension to the conventional ultrasound examination, by adding the liver stiffness quantification in the diagnostic algorithm. Whilst the most efficient elastographic techniques in staging liver fibrosis in NAFLD are vibration controlled transient elastography (VCTE) and 2D-Shear wave elastography (2D-SWE), VCTE presents the upside of assessing steatosis through the controlled attenuation parameter (CAP). Hereby, we have also critically reviewed the most important elastographic techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography (pSWE) and 2D-SWE. As our paper shows, elastography should not be considered as a substitute for FLL biopsy because of the stiffness values overlap. Furthermore, by using non-invasive, disease-specific surveillance tools, such as US elastography, a subset of the non-cirrhotic NAFLD patients at risk for developing HCC can be detected early, leading to a better outcome. A recent ultrasomics study exemplified the wide potential of 2D-SWE to differentiate benign FLLs from malignant ones, guiding the clinician towards the next steps of diagnosis and contributing to better long-term disease surveillance.

Usefulness of Different Imaging Modalities in Evaluation of Patients with Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are becoming some of the major health problems in well-developed countries, together with the increasing prevalence of obesity, metabolic syndrome, and all of their systemic complications. As the future prognoses are even more disturbing and point toward further increase in population affected with NAFLD/NASH, there is an urgent need for widely available and reliable diagnostic methods. Consensus on a non-invasive, accurate diagnostic modality for the use in ongoing clinical trials is also required, particularly considering a current lack of any registered drug for the treatment of NAFLD/NASH. The aim of this narrative review was to present current information on methods used to assess liver steatosis and fibrosis. There are several imaging modalities for the assessment of hepatic steatosis ranging from simple density analysis by computed tomography or conventional B-mode ultrasound to magnetic resonance spectroscopy (MRS), magnetic resonance imaging proton density fat fraction (MRI-PDFF) or controlled attenuation parameter (CAP). Fibrosis stage can be assessed by magnetic resonance elastography (MRE) or different ultrasound-based techniques: transient elastography (TE), shear-wave elastography (SWE) and acoustic radiation force impulse (ARFI). Although all of these methods have been validated against liver biopsy as the reference standard and provided good accuracy, the MRS and MRI-PDFF currently outperform other methods in terms of diagnosis of steatosis, and MRE in terms of evaluation of fibrosis.

Body mass index-based controlled attenuation parameter cut-offs for assessment of hepatic steatosis in non-alcoholic fatty liver disease

BACKGROUND AND AIM

In patients with liver disease, etiology and body mass index (BMI) affects controlled attenuation parameter (CAP) assessment using FibroScan. We aimed to assess the performance characteristics of CAP for hepatic steatosis in patients with non-alcoholic fatty liver disease (NAFLD) stratified into obese (BMI ≥ 30 kg/m²) and non-obese (BMI < 30 kg/m²) subgroups.

METHODS

In this prospective study, 219 consecutive adult NAFLD patients, with an available FibroScan value (liver stiffness measurement-[LSM] and CAP) and liver biopsy, were included. Receiver operating characteristic curves were used for assessment of the CAP cut-off values predicting different stages of hepatic steatosis.

RESULTS

The mean ± standard deviation age of patients was 39.7 ± 10.5 years, 116 (53%) were males, and median (interquartile range) BMI was 31.8 (25.7-43.8) kg/m². One hundred (45.7%) and 119 (54.3%) patients were non-obese and obese, respectively. The median values of CAP and LSM were significantly higher among obese patients as compared with the non-obese ones: 333 (304-368) vs. 320 (296-345) dB/m, p = 0.002 and 8.3 (6.1-11.4) vs. 6.6 (5.7-10.3) kPa, p = 0.012, respectively. Among non-obese NAFLD, optimal CAP cut-off values for steatosis (S) ≥ S1, ≥ S2, and ≥ S3 were 275 dB/m, 319 dB/m, and 337 dB/m, respectively. The corresponding CAP values among obese patients were higher as 285 dB/m, 340 dB/m, and 355 dB/m, respectively. BMI independently predicted CAP on multivariate analysis. The discordance of 2-grades between CAP and biopsy measured steatosis was seen in 13% in non-obese and 19.3% in obese NAFLD. CAP overestimated steatosis more often than underestimating it, with a higher proportion in obese NAFLD.

CONCLUSION

In patients with NAFLD, interpretation of CAP requires consideration of BMI.

Ultrasonic liver steatosis quantification by a learning-based acoustic model from a novel shear wave sequence

BACKGROUND

An efficient and accurate approach to quantify the steatosis extent of liver is important for clinical practice. For the purpose, we propose a specific designed ultrasound shear wave sequence to estimate ultrasonic and shear wave physical parameters. The utilization of the estimated quantitative parameters is then studied.

RESULTS

Shear wave attenuation, shear wave absorption, elasticity, dispersion slope and echo attenuation were simultaneously estimated and quantified from the proposed novel shear wave sequence. Then, a regression tree model was utilized to learn the connection between the space represented by all the physical parameters and the liver fat proportion. MR mDIXON quantification was used as the ground truth for liver fat quantification. Our study included a total of 60 patients. Correlation coefficient (CC) with the ground truth were applied to mainly evaluate different methods for which the corresponding values were - 0.25, - 0.26, 0.028, 0.045, 0.46 and 0.83 for shear wave attenuation, shear wave absorption, elasticity, dispersion slope, echo attenuation and the learning-based model, respectively. The original parameters were extremely outperformed by the learning-based model for which the root mean square error for liver steatosis quantification is only 4.5% that is also state-of-the-art for ultrasound application in the related field.

CONCLUSIONS

Although individual ultrasonic and shear wave parameters were not perfectly adequate for liver steatosis quantification, a promising result can be achieved by the proposed learning-based acoustic model based on them.

Application of transient elastography in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic liver disease worldwide. Although it has become one of the leading causes of cirrhosis and hepatocellular carcinoma in the Western world, the proportion of NAFLD patients developing these complications is rather small. Therefore, current guidelines recommend non-invasive tests for the initial assessment of NAFLD. Among the available non-invasive tests, transient elastography by FibroScan^® (Echosens, Paris, France) is commonly used by hepatologists in Europe and Asia, and the machine has been introduced to the United States in 2013 with rapid adoption. Transient elastography measures liver stiffness and the controlled attenuation parameter simultaneously and can serve as a one-stop examination for both liver steatosis and fibrosis. Liver stiffness measurement also correlates with clinical outcomes and can be used to select patients for varices screening. Although obesity is a common reason for measurement failures, the development of the XL probe allows successful measurements in the majority of obese patients. This article reviews the performance and limitations of transient elastography in NAFLD and highlights its clinical applications. We also discuss the reliability criteria for transient elastography examination and factors associated with false-positive liver stiffness measurements.

Nonalcoholic Fatty Liver Disease: An Update on the Diagnosis

Nonalcoholic fatty liver disease (NAFLD) is a common liver disease and a major cause of related complications such as cirrhosis and hepatocellular carcinoma (HCC). NAFLD progresses through the stages of simple steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and HCC. However, NAFLD usually cannot be diagnosed in a timely manner, which is largely attributed to the asymptomatic features of NAFLD patients and the lack of an effective and accurate noninvasive screening approach. Although liver biopsy has been recognized as a gold standard for diagnosing NAFLD, this approach is not suitable for screening and monitoring NAFLD because of its high cost and invasiveness. Several noninvasive screening and diagnostic systemic assessments have been developed in recent years for NAFLD evaluation. Here we summarize the current status and methods for NAFLD diagnosis, including both noninvasive (imaging, biomarkers) and invasive (liver biopsy) assessments. We further discuss the advantages and disadvantages of these developed diagnostic approaches for NAFLD.

Effect of Non-alcoholic Fatty Liver Disease on Transaminase Levels and Transient Elastography in Patients with Chronic Hepatitis B

Objective To investigate the effects of non-alcoholic fatty liver disease on aminotransferase (ALT) levels and transient elastography in patients with chronic hepatitis B (CHB). Methods A cross-sectional study of 230 patients with CHB and ALT levels up to two times the upper limits of normal, of one-year duration, from June 2018 to May 2019. The demographic, clinical, and laboratory characteristics of each patient were collected. Transient elastography was performed to evaluate controlled attenuation parameter (CAP or steatosis) and liver stiffness (fibrosis). Results A total of 161 (70%) patients were overweight, with over two-thirds (166; 72.2%) having elevated ALT >35 U/L. Three-fourths of the patients (178; 77.4%) had a hepatitis B virus (HBV) deoxyribonucleic (DNA) level of less than 2000 IU/ml. Steatosis was detected in 166 (72.2%) patients while fibrosis of F2 or more in 88 (38.3%). Multivariate regression analysis showed that weight, homeostatic model assessment of insulin resistance (HOMA-IR), and elevated ALT levels of more than 35 were independently associated with higher CAP values (p= 0.019, 0.001, and 0.004, respectively). Age, insulin levels, and platelet counts were independently associated with liver elasticity (p=0.00, 0.002, and 0.028, respectively). HBV DNA levels did not show any significant association with CAP score, liver stiffness, and HOMA-IR or ALT level. Among those with an elevated ALT of 35 or above (n=166), 124 patients had HBV DNA levels less than 2000 IU/ml. Out of these, 97 (78.2%) patients had steatosis and 51 (41.1%) had F2 or more fibrosis. Conclusion A significant number of patients with CHB with mildly elevated ALT levels are overweight, have significant steatosis and fibrosis, but low HBV DNA levels. This aspect is important while making decisions regarding hepatitis B treatment.

A review of the use of transient elastography in the assessment of fibrosis and steatosis in the post-liver transplant patient

Liver biopsy is considered the gold standard method for diagnosing and staging liver disease, particularly in the post-liver transplant setting. Given the invasive nature of biopsy, alternate means for accurately assessing liver fibrosis and steatosis are preferred especially as the number of patients with fatty liver disease is increasing. Transient elastography has been validated as a useful tool for evaluation of liver fibrosis, as has controlled attenuation parameter index as a tool for assessing steatosis. It is a non-invasive, rapid, and highly reproducible approach to demonstrate the presence of fibrosis among non-transplant patients with chronic liver disease of various etiologies. However, it has not yet found wide acceptance in liver transplant recipients. There are few published studies evaluating the merits and applicability of transient elastography to assess allografts after liver transplantation. We review the published data on the use of transient elastography with concurrent controlled attenuation parameter in liver transplant recipients and recommend its greater use to follow allograft function over time.

Moderate to severe hepatic steatosis leads to overestimation of liver stiffness measurement in chronic hepatitis B patients without significant fibrosis

BACKGROUND

Liver stiffness measurement (LSM) by transient elastography is a noninvasive method for the diagnosis of hepatic fibrosis. The impact of hepatic steatosis on LSM remains to be explored.

AIM

To determine whether LSM is affected by hepatic steatosis in patients with chronic hepatitis B (CHB).

METHODS

Consecutive patients with biopsy-proven CHB were prospectively enrolled. Hepatic steatosis was classified by pathology as none (S0, <5%), mild (S1, 5%-33%), and moderate-severe (S2-3, >33%), and quantitatively by controlled attenuation parameter (CAP) as CAP S0 (≤247 dB/m), CAP S1 (248-267 dB/m) and CAP S2-3 (≥268 dB/m). Liver fibrosis was assessed by METAVIR classification and noninvasively by LSM.

RESULTS

The prevalence of non-alcoholic fatty liver disease (n = 223) in CHB patients (n = 593) was 37.6%. Forty-eight belonged to S2-3 and 127 belonged to CAP S2-3. In patients without significant fibrosis (F0-1), the median LSM (kPa) was 7.4 in S2-3 and 7.1 in CAP S2-3, which was significantly higher than that in S0/S1 (P = 0.005) and CAP S0/S1 (P = 0.003). No significant difference was found in significant fibrosis (F2-4). For LSM identifying significant fibrosis (F2-4), the negative predictive value was higher in CHB patients with CAP ≥ 268 compared to those with CAP < 268 (0.81 vs 0.73); the positive predictive value was lower in CAP ≥ 268 than its counterpart (0.65 vs 0.76).

CONCLUSIONS

Moderate-severe steatosis increased the LSM value in CHB patients without significant fibrosis. A CAP ≥ 268 did not affect LSM for ruling out, but it slightly affected LSM for ruling in significant fibrosis.

TRIAL REGISTRATION

ChiCTR-DDT-13003983.

Wavelet-based Computationally-Efficient Computer-Aided Characterization of Liver Steatosis using Conventional B-mode Ultrasound Images

Hepatic steatosis occurs when lipids accumulate in the liver leading to steatohepatitis, which can evolve into cirrhosis and consequently may end with hepatocellular carcinoma. Several automatic classification algorithms have been proposed to detect liver diseases. However, some algorithms are manufacturer-dependent, while others require extensive calculations and consequently prolonged computational time. This may limit the development of real-time and manufacturer-independent computer-aided detection of liver steatosis. This work demonstrates the feasibility of a computationally-efficient and manufacturer-independent wavelet-based computer-aided liver steatosis detection system using conventional B-mode ultrasound (US) imaging. Seven features were extracted from the approximation part of the second-level wavelet packet transform (WPT) of US images. The proposed technique was tested on two datasets of ex-vivo mice livers with and without gelatin embedding, in addition to a third dataset of in-vivo human livers acquired using two different US machines. Using the gelatin-embedded mice liver dataset, the technique exhibited 98.8% accuracy, 97.8% sensitivity, and 100% specificity, and the frame classification time was reduced from 0.4814 s using original US images to 0.1444 s after WPT preprocessing. When the other mice liver dataset was used, the technique showed 85.74% accuracy, 84.4% sensitivity, and 88.5% specificity, and the frame classification time was reduced from 0.5612s to 0.2903 s. Using human liver image data, the best classifier exhibited 92.5% accuracy, 93.0% sensitivity, 91.0% specificity, and the classification time was reduced from 0.660 s to 0.146 s. This technique can be useful for developing computationally-efficient and manufacturer-independent noninvasive CAD systems for fatty liver detection.

Feasibility study and reference values of FibroScan 502 with M probe in healthy preschool children aged 5 years

Background

Transient elastography (TE) using FibroScan with M probe has been widely used in adults for controlled attenuation parameter (CAP) and liver stiffness measurement (LSM). In this study, we aimed to assess the feasibility of this approach and reference values of CAP and LSM in healthy preschool children aged 5 years.

Methods

FibroScan-502 with M probe (Echosens, Paris, France) and bioelectrical impedance analysis (InBody 720, Biospace, South Korea) were prospectively conducted in healthy children aged 5 years from the Shanghai Prenatal Cohort Study. Linear regression models and piece-wise linear regression models were used to explore the factors associated with CAP and LSM.

Results

The success rate of a valid TE measurement was 96.5% in 452 healthy preschool children aged 5 years, and 436 children with 236 boys were included for further study. The median, inter quartile range (IQR) and the 5th–95th percentiles of CAP values were 171.50, 162.07–188.13 and 154.21–214.53 dB/m, respectively. The median, mean ± standard deviation and the 5th–95th percentiles of LSM were 3.20, 3.28 ± 0.86 and 2.00–4.78 kPa, respectively. In multivariate linear regression analyses, the CAP but not the LSM value was significantly positively correlated with such anthropometric index as body weight, body mass index, waist circumference, body fat content and body fat percentage.

Conclusions

FibroScan-502 with M-probe can be used to measure CAP and LSM in preschool children aged 5 years. The 95th percentiles of CAP values and LSM were 214.53 dB/m and 4.78 kPa, respectively. Further study should be performed to explore the cut-off values of CAP and LSM for diagnosis of hepatic steatosis and fibrosis in children.

Could semiquantitative analysis of real-time ultrasound elastography distinguish more liver parenchyma alterations of nonalcoholic fatty liver disease in patients with polycystic ovary syndrome?

OBJECTIVE

Nonalcoholic fatty liver disease is the commonest diffuse liver disease, of which women with polycystic ovary syndrome are at an increased risk. The aim of the present study was to assess the diagnostic value of the semiquantitative strain parameters of real-time ultrasound elastography for nonalcoholic fatty liver disease in patients with polycystic ovary syndrome.

SUBJECTS AND METHODS

Thirty-five polycystic ovary syndrome patients with nonalcoholic fatty liver disease, 70 polycystic ovary syndrome patients without nonalcoholic fatty liver disease, and 70 healthy female controls of reproductive age were included. All participants underwent ultrasonic examination and semiquantitative analysis of real-time ultrasound elastography of the liver.

RESULTS

Main semi quantitative strain parameters, such as average strain value, differed significantly among groups polycystic ovary syndrome with nonalcoholic fatty liver disease, polycystic ovary syndrome without nonalcoholic fatty liver disease, and control (87.02 ± 10.16 vs. 96.31 ± 11.44 vs. 104.49 ± 7.28, p < 0.001). Clinical and laboratory parameters differed significantly between the two subgroups with low or high average strain value. For diagnostic value of average strain value for elevated aminotransferase, the area under the curve was 0.808 (range 0.721-0.895). In multiple linear regression analysis, polycystic ovary syndrome, waist circumference, and metabolic syndrome were stand-alone independent factors associated with average strain value among subjects without nonalcoholic fatty liver disease.

CONCLUSION

Semiquantitative real-time ultrasound elastography analysis could distinguish liver parenchyma alterations in patients with polycystic ovary syndrome more sensitively. The diagnostic value of the proposed method for nonalcoholic fatty liver disease need further research.

Diagnostic and Treatment Implications of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) affects 75 to 100 million adults in the United States and is the leading cause of chronic liver disease worldwide, fueled by the rising epidemic of obesity and metabolic syndrome. NAFLD is the hepatic manifestation of metabolic syndrome; thus, accurately assessing and managing comorbid metabolic syndrome components is paramount. Nonalcoholic steatohepatitis (NASH) is a subset of NAFLD that includes a more progressive and advanced form of the disease, with a greater risk of fibrosis progression. Correctly diagnosing and staging NAFLD and distinguishing the subset of NASH patients is not only critical for disease monitoring and prognostication, but also holds potential implications for therapies. Although the current therapeutic landscape for NAFLD does not offer many options, future therapies are on the horizon. Properly staging the severity of disease and fibrosis is especially important when considering the eligibility and cost-effectiveness of these therapies.

The Circulating Micro-RNAs (-122, -34a and -99a) as Predictive Biomarkers for Non-Alcoholic Fatty Liver Diseases

BACKGROUND

It remains essential for patient safety to develop non-invasive diagnostic tools to diagnose non-alcoholic fatty liver rather than invasive techniques.

AIM

Our case-control study was to address the value of circulating miRNAs as a potential non-invasive biomarker for the diagnosis of non-alcoholic fatty acid diseases (NAFLD) and monitoring of disease progression.

METHODS

Routine clinical assessment, laboratory tests, anthropometric study, and liver biopsy results reported for 210 patients with NAFLD (124 patients of simple steatosis (SS) and 86 of non-alcoholic steatohepatitis (NASH)). Apparently matched for age and gender, healthy participants (n= 90) were enrolled as a control group. Serum samples were tested for micro-RNAs (-122, -34a and -99a) by quantitative-PCR.

RESULTS

By histopathology, 124 of the NAFLD group were of SS and 86 patients were of NASH. Compared with the control subjects, both mi-RNA-122 and -34a levels were increased in NAFLD (p< 001) and at a cut-off = 1.261, mi-RNA-122 had 92% sensitivity, 85% specificity to differentiate NAFLD from healthy controls, while mi-RNA-99a were significantly decreased in NAFLD patients with an observed decrease in disease severity, and at a cut-off = 0.46, miRNA-99a had 94% sensitivity and 96% specificity to discriminate SS from NASH.

CONCLUSION

The integration of a circulating mi-RNA panel to diagnose NAFLD cases and to discriminate between SS and NASH. Large-scale study is still needed to verify the other mi-RNA profiles and their role in NAFLD pathogenesis and targeting therapy.

Controlled Attenuation Parameter for Assessment of Hepatic Steatosis in Indian Patients

BACKGROUND/AIMS

The gold standard method for measurement of hepatic steatosis is liver histology. Controlled Attenuation Parameter (CAP) can measure hepatic steatosis non-invasively. We aimed to assess the accuracy of CAP for detection of hepatic steatosis.

METHODS

A total of 462 patients (May 2012-January 2017)-89 non-alcoholic fatty liver disease, 182 chronic hepatitis B, 88 chronic hepatitis C and 103 patients with other etiologies who underwent simultaneous liver biopsy and CAP estimation using Transient Elastography (TE) were included. Steatosis was graded as S0: steatosis in 0-5% of hepatocytes, S1: 6-33%, S2: 34-66% and S3: 67-100%. Receiver Operating Characteristic (ROC) curves were plotted to evaluate the accuracy of CAP in detecting hepatic steatosis. Predictors of CAP were assessed by multivariate linear regression model.

RESULTS

The mean age ± SD was 33.8 ± 11.6 years; 296 (64.1%) were males. On liver histology, steatosis grades S0, S1, S2 and S3 were seen in 331 (71.6%), 74 (16.0%), 39 (8.4%) and 18 (3.9%), respectively. The median CAP (IQR) values for S0, S1, S2, and S3 steatosis were 206 (176-252) dB/m, 295 (257-331) dB/m, 320 (296-356) dB/m, and 349 (306-363) dB/m, respectively. For estimation of ≥S1, ≥S2, and ≥S3 using CAP, AUROC were 0.879, 0.893, and 0.883, respectively. In multivariate analysis, only BMI (OR 1.18; CI, 1.11-1.26, P < 0.001) and grade of hepatic steatosis (grade 1, OR, 3.94; 95% CI, 1.58-9.84, P = 0.003; grade 2, OR 42.04; 95% CI, 4.97-355.31, P = 0.001 and grade 3, OR 35.83; 95% CI 4.31-297.61, P = 0.001) independently predicted CAP.

CONCLUSIONS

CAP detects hepatic steatosis with good accuracy in Indian patients with various etiologies.

Quantitative Hepatic Fat Quantification in Non-alcoholic Fatty Liver Disease Using Ultrasound-Based Techniques: A Review of Literature and Their Diagnostic Performance

Non-alcoholic fatty liver disease is a condition that is characterized by the presence of >5% fat in the liver and affects more than one billion people worldwide. If adequate and early precautions are not taken, non-alcoholic fatty liver disease can progress to cirrhosis and death. The current reference standard for detecting hepatic steatosis is a liver biopsy. However, because of the potential morbidity associated with liver biopsies, non-invasive imaging biomarkers have been extensively investigated. Magnetic resonance imaging-based methods have proven accuracy in quantifying liver steatosis; however, these techniques are costly and have limited availability. Ultrasound-based quantitative imaging techniques are increasingly utilized because of their widespread availability, ease of use and relative cost-effectiveness. Several ultrasound-based liver fat quantification techniques have been investigated, including techniques that measure changes in the acoustic properties of the liver caused by the presence of fat. In this review, we focus on quantitative ultrasound approaches and their diagnostic performance in the realm of non-alcoholic fatty liver disease.

Validity of ultrasonography to assess hepatic steatosis compared to magnetic resonance spectroscopy as a criterion method in older adults

Background

The rising prevalence of obesity has made hepatic steatosis an increasingly common issue. Ultrasound is generally used in clinical practice to assess steatosis, but its accuracy has been inconsistent across studies. We aimed to determine the validity of ultrasound to diagnose hepatic steatosis when compared to the criterion method proton magnetic resonance spectroscopy (MRS) in older individuals.

Methods

A total of 72 healthy white European individuals (n = 42 men; n = 30 women aged 67–76 years) participating in the Hertfordshire Birth Cohort Physical Activity trial had hepatic steatosis assessed by ultrasound and MRS. The ultrasound scans were graded as normal, mild, moderate and severe steatosis, while hepatic fat content above 5.5% by MRS was used as a cut-off for steatosis.

Results

18 participants (25%) had a level of hepatic fat measured by MRS consistent with diagnosis of steatosis. The sensitivity and specificity of ultrasound in diagnosing hepatic steatosis (mild/moderate/severe vs normal) were 96% (95% CI: 87–99.6%) and 94% (95% CI: 73–100%) respectively, although overlap in MRS hepatic fat content was observed between the ultrasound categories.

Conclusions

Ultrasound is a valid method for detecting the presence or absence of hepatic steatosis in older adults and can be used as an alternative tool in both clinical investigations and epidemiological studies, when other imaging techniques are not feasible.

Combined Surgical Techniques for the Management of Malignant Glaucoma

Purpose

To characterize new combined surgical techniques for the management of malignant glaucoma.

Methods

In a retrospective, interventional case series, goniosynechialysis, peripheral iridectomy, zonulo-hyaloidectomy, and anterior vitrectomy, with or without peripheral capsulectomy, were performed on nine eyes. If the patient was phakic, we performed both phacoemulsification and intraocular lens implantation.

Results

Resolution of malignant glaucoma was achieved in all cases with anterior chamber deepening. Topical antiglaucoma medications were used to control the intraocular pressure in one eye. No recurrence was observed after a median follow-up of 9 months. No complications occurred during surgery or the postoperative period.

Conclusions

The combined surgical methods can completely eliminate blockade and aqueous misdirection and represent a promising treatment for malignant glaucoma.

The correlation between controlled attenuation parameter and metabolic syndrome and its components in middle-aged and elderly nonalcoholic fatty liver disease patients

This study aims to investigate the correlation between controlled attenuation parameter (CAP) and metabolic syndrome (MetS) and its components in middle-aged and elderly nonalcoholic fatty liver disease (NAFLD) patients.Middle-aged and elderly patients with NAFLD, who visited our hospital from June 2016 to May 2017, were enrolled as study subjects, whereas middle-aged and elderly patients without liver disease were enrolled as controls in the same period. The prevalence of MetS, MetS components, and the different numbers of MetS components were compared among patients with different CAP values.As the CAP value increased, the prevalence of MetS, MetS components, and the different numbers of MetS components significantly increased. The CAP value was positively correlated with the prevalence of MetS, obesity, hypertriglyceridemia, hypertension, hyperglycemia, hyperuricemia, and the number of MetS components, and was negatively correlated with the prevalence of hypo-high-density-lipoprotein cholesterolemia.CAP values are closely correlated to MetS and its components in middle-aged and elder NAFLD patients. CAP may be an indicator of risk of MetS and the severity of metabolic disorders in middle-aged and elderly NAFLD patients.

Relationship between Serum Cytokeratin-18, Control Attenuation Parameter, NAFLD Fibrosis Score, and Liver Steatosis in Nonalcoholic Fatty Liver Disease

BACKGROUNDS

The aim of this study was to appraise the relationship between serum fragmented cytokeratin-18(CK-18), controlled attenuation parameter (CAP), and liver steatosis assessed by ultrasound (US) in nonalcoholic fatty liver disease (NAFLD) patients.

METHODS

Patients who underwent abdominal US were recruited, followed with measurement of CAP using Fibroscan^® and serum fragmented CK-18 using enzyme-linked immunosorbent assay. The degree of liver steatosis assessed by US was categorized into mild (S1), moderate (S2), and severe (S3).

RESULTS

A total of 109 patients were included in our study. CAP and fragmented CK-18 level were significantly correlated with liver steatosis grade with r_s = 0.56 and 0.68, p=0.001, respectively. NAFLD Fibrosis Score was poorly correlated with liver steatosis grade (r_s=-0.096, p=0.318). Using fragmented CK-18 level, area under receiver operating characteristic (AUROC) curves for S≥2 and S≥3 were excellent (0.82 and 0.84, respectively). Using CAP, AUROC curves for detection of S≥2 and S≥3 were good (0.76, 0.77, respectively). We also proposed cut-off value of CAP to detect S≥2 and S≥3 to be 263 and 319db/m, respectively, and fragmented CK-18 level to detect S≥2 and S≥3 (194 and 294 U/L, respectively).

CONCLUSIONS

Both the fragmented CK-18 level and the CAP, but not NAFLD Fibrosis Score, were well correlated with hepatic steatosis grade as assessed by US.

Imaging of Hepatic Fibrosis

PURPOSE OF REVIEW

The purpose of this review is to discuss the current imaging techniques for non-invasive assessment of liver fibrosis (LF).

RECENT FINDINGS

Elastography-based techniques are the most widely used imaging methods for the evaluation of LF. Currently, MR elastography (MRE) is the most accurate non-invasive method for detection and staging of LF. Ultrasound-based vibration-controlled transient elastography (VCTE) is the most widely used as it can be easily performed at the point of care but has technical limitations especially in the obese. Innovations and technical improvements continue to evolve in elastography for improving accuracy and avoiding misinterpretation from confounding factors. Other imaging methods including diffusion-weighted imaging (DWI), hepatocellular contrast-enhanced (HCE) MRI, T1 relaxometry, T1ρ imaging, textural analysis, liver surface nodularity, susceptibility-weighted imaging, and perfusion imaging are promising but need further evaluation and clinical validation. MRE is the most accurate imaging technique for assessment of LF.

Controlled attenuation parameter in NAFLD identifies risk of suboptimal glycaemic and metabolic control

AIMS

To examine the relationship between steatosis quantified by controlled attenuation parameter (CAP) values and glycaemic/metabolic control.

METHODS

230 patients, recruited from an Endocrine clinic or primary care underwent routine Hepatology assessment, with liver stiffness measurements and simultaneous CAP. Multivariable logistic regression was performed to identify potential predictors of Metabolic Syndrome (MetS), HbA1c ≥ 7%, use of insulin, hypertriglyceridaemia and CAP ≥ 300 dB/m.

RESULTS

Patients were 56.7 ± 12.3 years of age with a high prevalence of MetS (83.5%), T2DM (81.3%), and BMI ≥ 40 kg/m² (18%). Median CAP score was 344 dB/m, ranging from 128 to 400 dB/m. BMI (aOR 1.140 95% CI 1.068-1.216), requirement for insulin (aOR 2.599 95% CI 1.212-5.575), and serum ALT (aOR 1.018 95% CI 1.004-1.033) were independently associated with CAP ≥ 300 dB/m. Patients with CAP interquartile range < 40 (68%) had a higher median serum ALT level (p = 0.029), greater prevalence of BMI ≥ 40 kg/m² (p = 0.020) and higher median CAP score (p < 0.001). Patients with higher CAP scores were more likely to have MetS (aOR 1.011 95% CI 1.003-1.019), HBA1c ≥ 7 (aOR 1.010 95% CI 1.003-1.016), requirement for insulin (aOR 1.007 95% CI 1.002-1.013) and hypertriglyceridemia (aOR 1.007 95% CI 1.002-1.013).

CONCLUSIONS

Our data demonstrate that an elevated CAP reflects suboptimal metabolic control. In diabetic patients with NAFLD, CAP may be a useful point-of-care test to identify patients at risk of poorly controlled metabolic comorbidities or advanced diabetes.

Nonalcoholic Fatty Liver Disease Cirrhosis: A Review of Its Epidemiology, Risk Factors, Clinical Presentation, Diagnosis, Management, and Prognosis

Cirrhosis is the common end stage of a number of chronic liver conditions and a significant cause of morbidity and mortality. With the growing epidemic of obesity and metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide and will become one of the leading causes of cirrhosis. Increased awareness and understanding of NAFLD cirrhosis are essential. To date, there has been no published systematic review on NAFLD cirrhosis. Thus, this article reviews recent studies on the epidemiology, risk factors, clinical presentation, diagnosis, management, and prognosis of NAFLD cirrhosis.

Noninvasive Quantitative Detection Methods of Liver Fat Content in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) ranges from simple steatosis to NAFLD-related liver cirrhosis and is a main cause of chronic liver diseases. Patients with nonalcoholic steatohepatitis and fibrosis are at a great risk of the progression to cirrhosis or hepatocellular carcinoma, both of which are tightly associated with liver-related mortality. Liver biopsy is still the gold standard for the diagnosis of NAFLD, but some defects, such as serious complications, sampling error and variability in histologic evaluation among pathologists, remain problematic. Therefore, noninvasive, repeatable and accurate diagnostic methods are urgently needed. Ultrasonography is a well-established and lower-cost imaging technique for the diagnosis of hepatic steatosis, especially suitable for population census, but limited by its low sensitivity to diagnose mild steatosis and being highly operator-dependent. Computed tomography also lacks the sensitivity to detect mild steatosis and small changes in fat content, and presents a potential radiation hazard. Controlled attenuation parameter based on the FibroScan^® technology is a promising tool for noninvasive semiquantitative assessment of liver fat content, but the accuracy rate depends on the operator's expertise and is affected by age, width of the intercostal space, skin capsular distance and body mass index. Magnetic resonance imaging and magnetic resonance spectroscopy are regarded as the most accurate quantitative methods for measuring liver fat content in clinical practice, especially for longitudinal follow up of NAFLD patients. In this review, we mainly introduce the current imaging methods that are in use for evaluation of liver fat content and we discuss the advantages and disadvantages of each method.

Association of non-alcoholic steatohepatitis with subclinical myocardial dysfunction in non-cirrhotic patients

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is associated with increased cardiovascular risk. Among categories of NAFLD, hepatic fibrosis is most likely to affect mortality. Myocardial function and its energy metabolism are tightly linked, which might be altered by an insulin resistant condition such as NAFLD. We investigated whether hepatic steatosis and fibrosis were associated with myocardial dysfunction relative to myocardial glucose uptake.

METHODS

A total of 308 patients (190 without NAFLD, 118 with NAFLD) were studied in a tertiary care hospital. Myocardial glucose uptake was evaluated at fasted state using [¹⁸F]-fluorodeoxyglucose-positron emission tomography (¹⁸FDG-PET). Hepatic steatosis and fibrosis were assessed by transient liver elastography (Fibroscan®) with controlled attenuation parameter, which quantifies hepatic fat and by surrogate indices (fatty liver index and NAFLD fibrosis score). Cardiac structure and function were examined by echocardiogram.

RESULTS

Compared to those without NAFLD, patients with NAFLD had alterations in cardiac remodeling, manifested by increased left ventricular mass index, left ventricular end-diastolic diameter, and left atrial volume index (all p <0.05). Hepatic steatosis was significantly associated with left ventricular filling pressure (E/e' ratio), which reflects diastolic dysfunction (p for trend <0.05). Those without NAFLD were more likely to have higher myocardial glucose uptake compared to those with NAFLD. Significant hepatic fibrosis was also correlated with diastolic dysfunction and impaired myocardial glucose uptake. Using multivariable linear regression, E/e' ratio was independently associated with hepatic fibrosis (standardized β = 0.12 to 0.27; all p <0.05). Association between hepatic steatosis and E/e' ratio was also significant (standardized β = 0.10 to 0.15; all p <0.05 excluding the model adjusted for adiposity).

CONCLUSIONS

Hepatic steatosis and fibrosis are significantly associated with diastolic heart dysfunction. This association is linked with myocardial glucose uptake evaluated by ¹⁸FDG-PET.

LAY SUMMARY

Non-alcoholic fatty liver disease is associated with an increased risk of cardiovascular disease. More severe forms of non-alcoholic fatty liver disease, where hepatic fibrosis occurs, are linked to increased mortality. In this study, we have shown that hepatic steatosis and fibrosis are associated with subclinical myocardial dysfunction. This association is linked to altered myocardial glucose uptake.

MEASUREMENT OF CONTROLLED ATTENUATION PARAMETER: A SURROGATE MARKER OF HEPATIC STEATOSIS IN PATIENTS OF NONALCOHOLIC FATTY LIVER DISEASE ON LIFESTYLE MODIFICATION - A PROSPECTIVE FOLLOW-UP STUDY

ABSTRACT BACKGROUND: Liver biopsy is a gold standard method for hepatic steatosis assessment. However, liver biopsy is an invasive and painful procedure and can cause severe complications therefore it cannot be frequently used in case of follow-up of patients. Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). To evaluate hepatic steatosis, transient elastography with controlled attenuation parameter (CAP) measurement is an option now days. OBJECTIVE: Aim of this study is to evaluate role of measurement of controlled attenuation parameter, a surrogate marker of hepatic steatosis in patients of nonalcoholic fatty liver disease on lifestyle modification. METHODS: In this study, initially 37 participants were included who were followed up after 6 months with transient elastography, blood biochemical tests and anthropometric measurements. The results were analyzed by Multivariate linear regression analysis and paired samples t-test (Dependent t-test) with 95% confidence interval. Correlation is calculated by Pearson correlation coefficients. RESULTS: Mean CAP value for assessing hepatic steatosis during 1st consultation (278.57±49.13 dB/m) was significantly improved (P=0.03) after 6 months of lifestyle modification (252.91±62.02 dB/m). Only fasting blood sugar (P=0.008), weight (P=0.000), body mass index (BMI) (P=0.000) showed significant positive correlation with CAP. Only BMI (P=0.034) and weight (P=0.035) were the independent predictor of CAP value in NAFLD patients. CONCLUSION: Lifestyle modification improves the hepatic steatosis, and CAP can be used to detect the improvement of hepatic steatosis during follow-up in patients with NAFLD on lifestyle modification. There is no relation between CAP and Fibroscan score in NAFLD patients. Only BMI and weight can predict CAP value independently.

Low-dose attenuation correction in diagnosis of non-alcoholic fatty liver disease

BACKGROUND

Non-enhanced computed tomography (CT) is a valuable modality in the diagnosis of non-alcoholic fatty liver disease (NAFLD). However, it is not clear if low-dose CT attenuation correction (CTAC) scans have the same accuracy to diagnose NAFLD. Our aim is to evaluate the diagnostic accuracy of low-dose CTAC in the diagnosis of NAFLD using non-enhanced CT as a gold standard.

METHODS

A total of 864 patients who underwent a clinically indicated hybrid nuclear imaging scanning between May 2011 and April 2014 were included in the study. Diagnosis of fatty liver was established if an absolute liver attenuation was <40 Hounsfield units and/or a liver-to-spleen ratio was <1.1. The diagnostic accuracy parameters were calculated to detect NAFLD by low-dose CTAC using unenhanced CT as a gold standard.

RESULTS

The prevalence of fatty liver by diagnostic CT and low-dose attenuation correction were 9.9 and 12.9% (using liver attenuation <40HU and liver-to-spleen ratio <1.1), respectively, with 32.9 and 34.9% (using absolute liver attenuation or ratio-to-spleen criteria), correspondingly. Low-dose CTAC had sensitivity (81.3%), specificity (94.0%), positive predictive value (60.2%), and negative predictive value (97.8%) using both diagnostic criteria. Using either of the diagnostic criteria resulted in sensitivity (76.8%), specificity (83.5%), PPV (66.3%), and NPV (89.5%).

CONCLUSION

Low-dose CT could be used as a tool to rule out the presence of fatty liver if neither liver attenuation of less than 40 HU nor liver-to-spleen below 1.1 is present.

Validity criteria for the diagnosis of fatty liver by M probe-based controlled attenuation parameter

BACKGROUND & AIMS

Controlled attenuation parameter (CAP) can be performed together with liver stiffness measurement (LSM) by transient elastography (TE) and is often used to diagnose fatty liver. We aimed to define the validity criteria of CAP.

METHODS

CAP was measured by the M probe prior to liver biopsy in 754 consecutive patients with different liver diseases at three centers in Europe and Hong Kong (derivation cohort, n=340; validation cohort, n=414; 101 chronic hepatitis B, 154 chronic hepatitis C, 349 non-alcoholic fatty liver disease, 37 autoimmune hepatitis, 49 cholestatic liver disease, 64 others; 277 F3-4; age 52±14; body mass index 27.2±5.3kg/m²). The primary outcome was the diagnosis of fatty liver, defined as steatosis involving ≥5% of hepatocytes.

RESULTS

The area under the receiver-operating characteristics curve (AUROC) for CAP diagnosis of fatty liver was 0.85 (95% CI 0.82-0.88). The interquartile range (IQR) of CAP had a negative correlation with CAP (r=-0.32, p<0.001), suggesting the IQR-to-median ratio of CAP would be an inappropriate validity parameter. In the derivation cohort, the IQR of CAP was associated with the accuracy of CAP (AUROC 0.86, 0.89 and 0.76 in patients with IQR of CAP <20 [15% of patients], 20-39 [51%], and ≥40dB/m [33%], respectively). Likewise, the AUROC of CAP in the validation cohort was 0.90 and 0.77 in patients with IQR of CAP <40 and ≥40dB/m, respectively (p=0.004). The accuracy of CAP in detecting grade 2 and 3 steatosis was lower among patients with body mass index ≥30kg/m² and F3-4 fibrosis.

CONCLUSIONS

The validity of CAP for the diagnosis of fatty liver is lower if the IQR of CAP is ≥40dB/m. Lay summary: Controlled attenuation parameter (CAP) is measured by transient elastography (TE) for the detection of fatty liver. In this large study, using liver biopsy as a reference, we show that the variability of CAP measurements based on its interquartile range can reflect the accuracy of fatty liver diagnosis. In contrast, other clinical factors such as adiposity and liver enzyme levels do not affect the performance of CAP.

High value of controlled attenuation parameter predicts a poor antiviral response in patients with chronic hepatits B

BACKGROUND

Controlled attenuation parameter (CAP) is a non-invasive method for diagnosing hepatic steatosis based on vibration-controlled transient elastography. The objective of this study was to investigate the effect of high value of CAP on antiviral therapy in patients with chronic hepatitis B (CHB).

METHODS

Patients with CHB receiving enticavir for initial antiviral therapy were studied; they were divided into the high CAP group and normal CAP group at baseline according to the CAP values. The effect of the antiviral therapy between the two groups were compared at week 12, 24 and 48. Patients with high CAP value at baseline were divided into three subgroups, mild, moderate and severe elevation; the therapeutic response were compared among patients with normal CAP and subgroups of patients with elevated CAP.

RESULTS

A total of 153 patients were enrolled. Among them, 63 were in the high CAP group and 90 in the normal CAP group. Patients with high CAP had lower rates of ALT normalization and HBV DNA clearance in response to antiviral therapy compared with those with normal CAP at week 12, 24 and 48. Further analysis showed that the rate of ALT normalization in patients with mildly and moderately elevated CAP were significant lower than those with normal CAP at week 12 and 24; while the difference was not significant between the patients with normal CAP and those with severely elevated CAP. The rate of HBV DNA clearance was significantly lower in patients with severely elevated CAP compared with those with normal CAP at week 12, 24 and 48.

CONCLUSION

CHB patients with high CAP had poor response to antiviral therapy.

A comparison of hepatic steatosis index, controlled attenuation parameter and ultrasound as noninvasive diagnostic tools for steatosis in chronic hepatitis B

AIMS

To evaluate the value of noninvasive tools for diagnosis of hepatic steatosis in patients with chronic hepatitis B (CHB).

METHODS

Consecutive treatment-naïve patients with CHB with body mass index less than 30kg/m² who underwent liver biopsy, ultrasound and FibroScan^® were enrolled. The diagnostic performance of controlled attenuation parameter (CAP), hepatic steatosis index (HSI) and ultrasound for hepatic steatosis compared with liver biopsy was assessed. The areas under receiver operating characteristics curves (AUROCs) were calculated to determine the diagnostic efficacy, with comparisons using the DeLong test.

RESULTS

CAP and HSI accuracies were significantly higher than that of ultrasound to detect patients with biopsy-proven mild steatosis (S1, 65.3%, 56.5%, respectively, vs. 17.7%, χ²=46.305, 31.736, both P<0.05)and moderate-severe (S2-3) steatosis (92.3%, 100%, respectively, vs. 53.8%, χ²=4.887, 7.800, P=0.037, 0.007, respectively). Both CAP and HSI had lower underestimation rates of steatosis grade than ultrasound (12%, 14.8%, respectively, vs. 29.5%, χ²=9.765, 6.452; P<0.05 for both), but they exhibited higher overestimation rates (30.5%, 38.2%, respectively, vs. 12.4%, χ²=39.222, 70.986; both P<0.05). The AUROCs of CAP and HSI were 0.780 (95% confidence intervals [CIs] 0.735-0.822) and 0.655 (95%CI 0.604-0.704) for S ≥1, 0.932 (95%CI 0.902-0.956) and 0.755 (95%CI 0.707-0.799) for S ≥2, 0.990 (95%CI 0.974-0.998) and 0.786 (95% CI 0.740-0.827) for S3, respectively.

CONCLUSION

CAP might be more accurate for detecting hepatic steatosis than HSI and ultrasound in patients with CHB, but further studies are needed to reduce the overestimation rates.

Factors affecting accuracy of controlled attenuation parameter by Fibrotouch in assessing hepatic steatosis

AIM

To explore the factors influencing controlled attenuation parameter (CAP) obtained by Fibrotouch in patients with non-alcoholic fatty liver disease (NAFLD).

METHODS

Patients with NAFLD diagnosed by liver biopsy in the First Affiliated Hospital of Zhengzhou University from December 2015 to December 2016 were collected. CAP was detected and recorded by Fibrotouch before liver biopsy. Clinical data were collected, including gender, age, body mass index (BMI), alanine transaminase, triacylglycerol (TG), fasting insulin, steatosis, lobular inflammation, ballooning, and fibrosis stage. Multiple linear regression analysis was used for identifying the factors influencing CAP.

RESULTS

Multiple linear regression analysis showed that CAP value was positively correlated with BMI (β = 0.216, P = 0.024), TG (β = 0.269, P = 0.022), steatosis (β = 0.448, P = 0.000), and ballooning (β = 0.200, P = 0.039) (F = 18.202, P < 0.001). The regression equation was CAP = 183.574 + 1.866 × BMI + 4.527 × TG + 15.602 × steatosis + 10.503 × ballooning. Single factor variance analysis of insulin level was performed in different degrees of hepatic steatosis, which suggested that insulin level had no significance to distinguish different degrees of steatosis (F = 2.664, P > 0.05).

CONCLUSION

The value of CAP is affected by BMI, TG, steatosis, and ballooning.

Individual patient data meta-analysis of controlled attenuation parameter (CAP) technology for assessing steatosis

BACKGROUND & AIMS

The prevalence of fatty liver underscores the need for non-invasive characterization of steatosis, such as the ultrasound based controlled attenuation parameter (CAP). Despite good diagnostic accuracy, clinical use of CAP is limited due to uncertainty regarding optimal cut-offs and the influence of covariates. We therefore conducted an individual patient data meta-analysis.

METHODS

A review of the literature identified studies containing histology verified CAP data (M probe, vibration controlled transient elastography with FibroScan®) for grading of steatosis (S0-S3). Receiver operating characteristic analysis after correcting for center effects was used as well as mixed models to test the impact of covariates on CAP. The primary outcome was establishing CAP cut-offs for distinguishing steatosis grades.

RESULTS

Data from 19/21 eligible papers were provided, comprising 3830/3968 (97%) of patients. Considering data overlap and exclusion criteria, 2735 patients were included in the final analysis (37% hepatitis B, 36% hepatitis C, 20% NAFLD/NASH, 7% other). Steatosis distribution was 51%/27%/16%/6% for S0/S1/S2/S3. CAP values in dB/m (95% CI) were influenced by several covariates with an estimated shift of 10 (4.5-17) for NAFLD/NASH patients, 10 (3.5-16) for diabetics and 4.4 (3.8-5.0) per BMI unit. Areas under the curves were 0.823 (0.809-0.837) and 0.865 (0.850-0.880) respectively. Optimal cut-offs were 248 (237-261) and 268 (257-284) for those above S0 and S1 respectively.

CONCLUSIONS

CAP provides a standardized non-invasive measure of hepatic steatosis. Prevalence, etiology, diabetes, and BMI deserve consideration when interpreting CAP. Longitudinal data are needed to demonstrate how CAP relates to clinical outcomes.

LAY SUMMARY

There is an increase in fatty liver for patients with chronic liver disease, linked to the epidemic of the obesity. Invasive liver biopsies are considered the best means of diagnosing fatty liver. The ultrasound based controlled attenuation parameter (CAP) can be used instead, but factors such as the underlying disease, BMI and diabetes must be taken into account. Registration: Prospero CRD42015027238.