Hepatic steatosis in obese Chinese children

Emerging role of lipophagy in liver disorders

Lipophagy is a selective degradation of lipids by a lysosomal-mediated pathway, and dysregulation of lipophagy is linked with the pathological hallmark of many liver diseases. Downregulation of lipophagy in liver cells results in abnormal accumulation of LDs (Lipid droplets) in hepatocytes which is a characteristic feature of several liver pathologies such as nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Contrarily, upregulation of lipophagy in activated hepatic stellate cells (HSCs) is associated with hepatic fibrosis and cirrhosis. Lipid metabolism reprogramming in violent cancer cells contributes to the progression of liver cancer. In this review, we have summarized the recent studies focusing on various components of the lipophagic machinery that can be modulated for their potential role as therapeutic agents against a wide range of liver diseases.

Comparison of Radiologists and Deep Learning for US Grading of Hepatic Steatosis

Background Screening for nonalcoholic fatty liver disease (NAFLD) is suboptimal due to the subjective interpretation of US images. Purpose To evaluate the agreement and diagnostic performance of radiologists and a deep learning model in grading hepatic steatosis in NAFLD at US, with biopsy as the reference standard. Materials and Methods This retrospective study included patients with NAFLD and control patients without hepatic steatosis who underwent abdominal US and contemporaneous liver biopsy from September 2010 to October 2019. Six readers visually graded steatosis on US images twice, 2 weeks apart. Reader agreement was assessed with use of κ statistics. Three deep learning techniques applied to B-mode US images were used to classify dichotomized steatosis grades. Classification performance of human radiologists and the deep learning model for dichotomized steatosis grades (S0, S1, S2, and S3) was assessed with area under the receiver operating characteristic curve (AUC) on a separate test set. Results The study included 199 patients (mean age, 53 years ± 13 [SD]; 101 men). On the test set (n = 52), radiologists had fair interreader agreement (0.34 [95% CI: 0.31, 0.37]) for classifying steatosis grades S0 versus S1 or higher, while AUCs were between 0.49 and 0.84 for radiologists and 0.85 (95% CI: 0.83, 0.87) for the deep learning model. For S0 or S1 versus S2 or S3, radiologists had fair interreader agreement (0.30 [95% CI: 0.27, 0.33]), while AUCs were between 0.57 and 0.76 for radiologists and 0.73 (95% CI: 0.71, 0.75) for the deep learning model. For S2 or lower versus S3, radiologists had fair interreader agreement (0.37 [95% CI: 0.33, 0.40]), while AUCs were between 0.52 and 0.81 for radiologists and 0.67 (95% CI: 0.64, 0.69) for the deep learning model. Conclusion Deep learning approaches applied to B-mode US images provided comparable performance with human readers for detection and grading of hepatic steatosis. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Tuthill in this issue.

Combination of the effect of ginger and anti‐inflammatory diet on children with obesity with nonalcoholic fatty liver disease: A randomized clinical trial

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in children. Following earlier reports on an increase in the prevalence of childhood obesity, NAFLD is now becoming increasingly common in children. Although no definitive cure exists, early management, early diagnosis, and treatment can reduce its complications. This study aims to determine the effectiveness of the combination of ginger and an anti-inflammatory diet (AID) in children with obesity on fatty liver management. This randomized clinical trial was conducted on 160 children with obesity aged 8-11 years, with a mean (SD) weight of 65.01 (9.67) kg, mean (SD) height of 139.87 (7.37) cm, and mean (SD) body mass index of 33.40 (5.59) kg/m². The study duration was 12 weeks. Children were divided into four groups: ginger (G), AID, ginger plus an AID (GPA), and control. Ginger capsules comprised 1000 mg of ginger, whereas the AID comprised fruits and vegetables, fish, turkey, and chicken (without skin) with lean meat, omega-3 sources, nuts, legumes, probiotic products, and elimination of inflammatory food. Following the intervention, serum fasting blood sugar and high-sensitivity C-reactive protein levels were significantly decreased in the AID (p = .006 and .002, respectively), G (p = .04 and <.001, respectively), and GPA (p <.001 in both cases, respectively) groups. Further, in the G and GPA groups, there was a significant decrease in body mass index (p = .04 in both cases, respectively), waist circumference (p = .009 and .003, respectively), waist-to-height ratio (p = .02 and .005, respectively), alanine aminotransferase (p = .004 and <.001, respectively), total cholesterol (p = .0002 and .0001, respectively) and low-density lipoprotein-cholesterol (p < .001 and <.001, respectively). Eventually, serum aspartate aminotransferase was decreased (p < .001) and high-density lipoprotein-cholesterol (p = .03) was increased significantly in the GPA group. As a main finding of this study, hepatic steatosis significantly decreased in the G and GPA groups. Ginger supplementation can effectively improve NAFLD in children, and its effectiveness was further increased when combined with an AID.

Information Entropy and Its Applications

Ultrasound is a first-line diagnostic tool for imaging many disease states. A number of statistical distributions have been proposed to describe ultrasound backscattering measured from tissues having different disease states. As an example, in this chapter we use nonalcoholic fatty liver disease (NAFLD), which is a critical health issue on a global scale, to demonstrate the capabilities of ultrasound to diagnose disease. Ultrasound interaction with the liver is typically characterized by scattering, which is quantified for the purpose of determining the degree of liver steatosis and fibrosis. Information entropy provides an insight into signal uncertainty. This concept allows for the analysis of backscattered statistics without considering the distribution of data or the statistical properties of ultrasound signals. In this chapter, we examined the background of NAFLD and the sources of scattering in the liver. The fundamentals of information entropy and an algorithmic scheme for ultrasound entropy imaging are then presented. Lastly, some examples of using ultrasound entropy imaging to grade hepatic steatosis and evaluate the risk of liver fibrosis in patients with significant hepatic steatosis are presented to illustrate future opportunities for clinical use.

The burden and sexual dimorphism with nonalcoholic fatty liver disease in Asian children: A systematic review and meta-analysis

BACKGROUND

Despite substantial attention paid to the epidemic of nonalcoholic fatty liver disease (NAFLD) in adults, data on the burden and sexual dimorphism of NAFLD in Asian children have not yet been synthesized.

METHODS

We conducted a literature search of 735 references up to April 2021. Pooled analyses, stratified analyses and meta-regression were all performed.

RESULTS

Thirty-three study populations were finally included. Nine of them comprising 20 595 children showed an overall NAFLD prevalence of 5.53% (95% CI 3.46%-8.72%), in which, 36.64% (95% CI, 27.99%-46.26%) NAFLD subjects had elevated levels of ALT. The prevalence rate of NAFLD increased about 1.6-fold from 2004 to 2010 to the last decade. Male predominant trends were observed in paediatric NAFLD (boys: 8.18%, 95% CI 4.93%-13.26%; girls: 3.60%, 95% CI 1.60%-7.87%). Moreover, meta-analysis showed that after 10 years of age, boys were more prone to have NAFLD than girls (OR = 1.75; P = .0012). In addition, the pooled prevalence of NAFLD increased sequentially in normal-weight (1.49%, 95% CI 0.88%-2.51%, n = 2610), overweight (16.72%, 95% CI 7.07%-34.65%, n = 1265) and obese children (50.13%, 95% CI 41.99%-58.27%, n = 6434 individuals). After full covariate adjustment, the multivariate meta-regression also showed that boy percentage (P = .0396) and body mass index (P < .0001) were positively correlated with prevalent NAFLD.

CONCLUSIONS

In Asia, paediatric NAFLD is becoming prevalent over the recent decades, particularly among obese children and boys after 10 years old. The hormonal and chromosomal origins of paediatric NAFLD dimorphism need further investigation.

Total cholesterol to high-density lipoprotein ratio and nonalcoholic fatty liver disease in a population with chronic hepatitis B

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is characterized by hypertriglyceridemia, increased low-density lipoprotein cholesterol levels, and reduced high-density lipoprotein cholesterol (HDL-C) particles. Previous studies have shown that the total cholesterol to high-density lipoprotein cholesterol ratio (TC/HDL-C) was superior to other lipid metabolism biomarkers for predicting NAFLD risk and could be a new indicator of NAFLD. However, the association between TC/HDL-C and NAFLD in patients with hepatitis B virus (HBV) has not yet been determined.

AIM

To investigate the association between TC/HDL-C and NAFLD in a population with chronic hepatitis B (CHB).

METHODS

In this study, 183 HBV-infected patients were enrolled. All participants underwent blood chemistry examinations and abdominal ultrasound. Univariate and multivariate logistic regression models, curve fitting analysis, and threshold calculation were used to assess the relationship between TC/HDL-C and NAFLD.

RESULTS

The overall prevalence of NAFLD was 17.49% (n = 32) in the 183 CHB participants. The TC/HDL-C of non-NAFLD and NAFLD patients were 3.83 ± 0.75 and 4.44 ± 0.77, respectively (P < 0.01). Logistic regression analysis showed that TC/HDL-C was not associated with NAFLD after adjusting for other pertinent clinical variables. However, at an optimal cutoff point of 4.9, a non-linear correlation between TC/HDL-C and NAFLD was detected. The effect size of the left and right sides of the inflection point were 5.4 (95% confidence interval: 2.3-12.6, P < 0.01) and 0.5 (95% confidence interval: 0.1-2.2, P = 0.39), respectively. On the left side of the inflection point, TC/HDL-C was positively associated with NAFLD. However, no significant association was observed on the right side of the inflection point.

CONCLUSION

This study demonstrated a non-linear correlation between TC/HDL-C and NAFLD in a population with CHB. TC/HDL-C was positively associated with NAFLD when TC/HDL-C was less than 4.9 but not when TC/HDL-C was more than 4.9.

Nonalcoholic Fatty Liver Disease in Children and Adolescents Taking Atypical Antipsychotic Medications: Protocol for a Systematic Review and Meta-analysis

Background

Atypical antipsychotics (AAP) are commonly prescribed to children and adolescents and are associated with important adverse effects including weight gain and metabolic syndrome. Nonalcoholic fatty liver disease (NAFLD) is not only the most common pediatric liver disease but is also associated with serious complications including liver cirrhosis.

Objective

Given that NAFLD and AAP are associated with metabolic syndrome, we aim to comprehensively examine the association between AAP and NAFLD in children and adolescents.

Methods

We will conduct a systematic review of studies exploring NAFLD in subjects younger than 18 years on AAP published in English between 1950 and 2020 following the PRISMA (Preferred Reporting items for Systematic Reviews and Meta-Analysis) guidelines.

Results

A PRISMA flowchart will be used present the study results after comprehensively reviewing studies on NAFLD in children and adolescents taking AAP. The first and second systematic searches will be conducted during December 2021. The results are expected to be published in June 2022.

Conclusions

This research project will serve as a foundation for future studies and assist in devising interventions and reforming clinical guidelines for using AAP to ensure improved patient safety.

International Registered Report Identifier (IRRID)

PRR1-10.2196/20168

Hepatic macrosteatosis in the US pediatric deceased liver donor population

INTRODUCTION

The pediatric obesity epidemic is associated with early development of hepatic macrosteatosis, a hallmark of non-alcoholic fatty LI disease, which is thought to be more rapidly progressive in children than adults. Macrosteatosis in adult allografts is associated with allograft loss, but this has not been examined in pediatric donors.

METHODS

We studied all pediatric potential whole LI donors (2005-2018) who had a LI biopsy in the SRTR (n = 862) and whose LI was transplanted (n = 862). Macrosteatosis was abstracted from biopsy reports and compared to values in the SRTR standard analytic file. Recipients of macrosteatotic pediatric allografts were matched 1:1 to recipients of non-macrosteatotic pediatric allografts by propensity score matching on donor/recipient variables. All-cause allograft loss was estimated via Kaplan-Meier analysis and Cox proportional hazards model.

RESULTS

From 2005 to 2018, the proportion of pediatric donors (age ≥2 years) with obesity increased (14.8% to 21.7%; p < .001), as did the proportion of pediatric deceased whole LI-only donor allografts with macrosteatosis (n = 10 648; 1.8% to 3.9%; p < .001). The median degree of macrosteatosis among macrosteatotic donors was 10% (IQR 5-30). There were no significant differences in all-cause allograft loss between recipients of pediatric LI allografts with and without macrosteatosis at 90 days (p = .11) or 1 year (p = .14) post-transplant in Kaplan-Meier analysis or a Cox proportional hazards model (p > .05).

CONCLUSION

Obese pediatric LI donors have increased over time and were more likely to have hepatic macrosteatosis; however, pediatric macrosteatosis did not appear to adversely affect recipient outcomes.

Increased hepcidin levels and non-alcoholic fatty liver disease in obese prepubertal children: a further piece to the complex puzzle of metabolic derangements

INTRODUCTION

Several studies on obese youths and adults have reported increased hepcidin levels, which seems to be related to metabolic and iron metabolism alterations. The complete mechanisms involved in hepcidin increase remain to be elucidated, and particularly its role in the development of other known complications such as Nonalcoholic Fatty Liver Disease (NAFLD). NAFLD in prepubertal children might be of special interest in understanding the underlying mechanisms.

METHODS

Anthropometric measurements, liver ultrasonography, lipid profile, liver function, oxidative stress, inflammatory state, and iron metabolism were studied in 42 obese prepubertal children and 33 healthy controls. We, therefore, evaluated the presence of possible correlations between Hepcidin and the other metabolic variables, and the possible association between NAFLD and iron metabolism.

RESULTS

Hepcidin levels were significantly increased in the obese prepubertal children (p=0.001) with significant differences between obese children with and without NAFLD (p=0.01). Blood iron was lower in obese children (p=0.009). In the obese group, a negative correlation between hepcidin and both blood iron levels (p=0.01) and LagPHASE (p=0.02) was found. In addition, a positive association between hepcidin and NAFLD (p=0.03) was detected.

CONCLUSIONS

We suggest that an increase in hepcidin levels may represent an early step in iron metabolism derangements and metabolic alterations, including NAFLD, in prepubertal obese children.

Defining paediatric metabolic (dysfunction)-associated fatty liver disease: an international expert consensus statement

The term non-alcoholic fatty liver disease (NAFLD), and its definition, have limitations for both adults and children. The definition is most problematic for children, for whom alcohol consumption is usually not a concern. This problematic definition has prompted a consensus to rename and redefine adult NAFLD associated with metabolic dysregulation to metabolic (dysfunction)-associated fatty liver disease (MAFLD). Similarities, distinctions, and differences exist in the causes, natural history, and prognosis of fatty liver diseases in children compared with adults. In this Viewpoint we, an international panel, propose an overarching framework for paediatric fatty liver diseases and an age-appropriate MAFLD definition based on sex and age percentiles. The framework recognises the possibility of other coexisting systemic fatty liver diseases in children. The new MAFLD diagnostic criteria provide paediatricians with a conceptual scaffold for disease diagnosis, risk stratification, and improved clinical and multidisciplinary care, and they align with a definition that is valid across the lifespan.

Relationship between Quantitative Sonographic Measurements and Serum Biochemical Parameters in Childhood Obesity

PURPOSE

We investigated the relationship between sonographic measurements of fatty liver and body mass index standard deviation score (BMI-Z score), abdominal wall fat thickness (AWFT), and serum biochemical parameters in childhood obesity.

METHODS

Anthropometric, laboratory, and ultrasonography data were obtained from 174 children with BMI-Z score >1. After the qualitative grading of hepatosteatosis (grades 0-3), the quantitative liver-kidney echogenicity ratio (LKER) was calculated using a software tool. Groups according to sex, age (AG-I to AG-III), BMI-Z score (BMG-I to BMG-III), and hepatosteatosis degree (HS-I and HS-II) were formed. The differences and distributions of the variables were statistically analyzed and compared among the groups.

RESULTS

Serum transaminase and glucose levels showed a positive correlation with LKER, whereas the HDL level showed a negative correlation. BMI-Z score and AWFT showed a positive correlation with fasting insulin level and HOMA-IR value. LKER was significantly higher in girls than in boys (p=0.008). In the AG-I group (age 3-8.9 years), the BMI-Z score was significantly higher, whereas AWFT was significantly lower than in the other age groups (p<0.001). The cutoff point of LKER for predicting grade 2 or higher steatosis (HS-II group) was determined to be 1.83. Cardiovascular disease risk was significantly higher in the HS-II group (p=0.035).

CONCLUSION

As a valuable quantitative measurement tool, LKER can be used for the sonographic screening of fatty liver. AWFT, on the basis of its correlation with fasting insulin level and HOMA-IR value, may be a useful sonographic parameter in the management of childhood obesity.

Prevalence and risk factors of steatosis and advanced fibrosis using transient elastography in the United States’ adolescent population

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in children and adolescents.

AIM

To determine the prevalence and risk factors of steatosis and advanced fibrosis using transient elastography (TE) in the United States’ adolescent population.

METHODS

Using the National Health and Nutrition Examination Survey 2017-2018, adolescent participants aged 13 to 17 years who underwent TE and controlled attenuation parameter (CAP) were included in this study. Forty-one factors associated with liver steatosis and fibrosis were collected. Univariate and multivariate linear regression analysis were used to identify statistically significant predictors.

RESULTS

Seven hundred and forty participants met inclusion criteria. Steatosis (S1-S3), based on CAP, and advanced fibrosis (F3-F4), based on TE, were present in 27% and 2.84% of the study population, respectively. Independent predictors of steatosis grade included log of alanine aminotransferase, insulin resistance, waist-to-height ratio, and body mass index. Independent predictors of fibrosis grade included steatosis grade, non-Hispanic black race, smoking history, and systolic blood pressure.

CONCLUSION

This study demonstrated a high prevalence of steatosis in the United States’ adolescent population. Almost 3% of United States’ adolescents had advanced fibrosis. These findings are concerning because a younger age of onset of NAFLD can lead to an earlier development of severe disease, including steatohepatitis, cirrhosis, and liver decompensation.

Conventional ultrasound for diagnosis of hepatic steatosis is better than believed

BACKGROUND

Hepatic steatosis is a condition frequently encountered in clinical practice, with potential progression towards fibrosis, cirrhosis, and hepatocellular carcinoma. Detection and staging of hepatic steatosis are of most importance in nonalcoholic fatty liver disease (NAFLD), a disease with a high prevalence of more than 1 billion individuals affected. Ultrasound (US) is one of the most used noninvasive imaging techniques used in the diagnosis of hepatic steatosis. Detection of hepatic steatosis with US relies on several conventional US parameters, which will be described. US is the first-choice imaging in adults at risk for hepatic steatosis. The use of some scoring systems may add additional accuracy especially in assessing the severity of hepatic steatosis.

SUMMARY

In the presented paper, we discuss screening and risk stratification, ultrasound features for diagnosing hepatic steatosis, B-mode criteria, focal fatty patterns and Doppler features of the hepatic vessels, and the value of the different US signs for the diagnosis of liver steatosis including classifying the severity of steatosis using different US scores. Limitations of conventional B-mode and Doppler features in the evaluation of hepatic steatosis are also discussed, including those in grading and assessing the complications of steatosis, namely fibrosis and nonalcoholic steatohepatitis.

KEY MESSAGES

Ultrasound is the first-line imaging examination for the screening and follow-up of patients with liver steatosis. The use of some scoring systems may add additional accuracy in assessing the severity of steatosis. Conventional B-mode and Doppler ultrasound have limitations in grading and assessing the complications of steatosis.

Utility of quantitative ultrasound in community screening for hepatic steatosis

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Quantitative ultrasound facilitates clinical grading of hepatic steatosis (the early stage of NAFLD). However, the utility of quantitative ultrasound as a first-line method for community screening of hepatic steatosis remains unclear. Therefore, this study aimed to investigate the utility of quantitative ultrasound to screen for hepatic steatosis and for metabolic evaluation at the community level. In total, 278 participants enrolled from a community satisfied the study criteria. Each subject underwent anthropometric and biochemical examinations, and abdominal ultrasound imaging was performed to measure the controlled attenuation (CAP), integrated backscatter (IB), and information Shannon entropy (ISE). The assessment outcomes were compared with the fatty liver index (FLI), hepatic steatosis index (HSI), metabolic syndrome (MetS), and insulin resistance to evaluate the screening performance through the area under the receiver operating characteristic curve (AUROC) and Delong's test. Ultrasound ISE, CAP, and IB were effective in screening hepatic steatosis, MetS, and insulin resistance. In screening for hepatic steatosis, the AUROCs of ISE, CAP, and IB were 0.85, 0.83, and 0.80 (the cutoff FLI = 60), respectively, and 0.84, 0.75, 0.77 (the cutoff HSI = 36), respectively, and those for the evaluation of MetS and insulin resistance were 0.79, 0.75, 0.79, respectively, and 0.83, 0.76, 0.78, respectively. Delong's test revealed that ISE outperformed CAP and IB for the detection of hepatic steatosis and insulin resistance (P < .05). Based on the present results, ultrasound ISE is a potential imaging biomarker during first-line community screening of hepatic steatosis and insulin resistance.

Predictors for incidence and remission of nonalcoholic fatty liver disease in obese children and adolescents

BACKGROUND/PURPOSE

The status of nonalcoholic fatty liver disease (NAFLD) can wax and wane over time in children. However, the factors affecting its incidence and remission remain elusive. We aimed to investigate NAFLD incidence, remission and predicting factors in obese children.

METHODS

Obese children aged 9-10 and 12-13 years were recruited from schools and followed up for 2 years. Liver ultrasonography was performed at baseline and Year 1. Alanine aminotransferase (ALT) concentrations were measured at baseline, Year 1 and Year 2. Elevated ALT was defined as above 26 U/L for boys and 22 U/L for girls. Four NAFLD susceptible genes, including PNPLA3, GCKR, TM6SF2 and MBOAT7, were genotyped. We analyzed the effects of these risk factors on the incidence and remission of NAFLD and elevated ALT.

RESULTS

At baseline, 86 of 440 (19.5%) subjects had ultrasonography-diagnosed NAFLD. At Year 1, of 264 subjects without NAFLD at baseline, 20 (7.6%) developed NAFLD. The baseline BMI z-score and increment in BMI z-score independently predicted incident NAFLD. Of the 68 subjects with NAFLD at baseline, 36 (52.9%) had NAFLD remission. Decrement in BMI z-score independently predicted NAFLD remission. The four studied NAFLD susceptible genes were not significantly associated with either the incidence or remission of NAFLD. In addition, changes in BMI z-score predicted the incidence and remission of elevated ALT from Year 1 to Year 2.

CONCLUSION

Obese children with increasing BMI are more likely to develop NAFLD and those with decreasing BMI are more likely to have NAFLD remission.

Changes in Liver Enzymes and Metabolic Profile in Adolescents with Fatty Liver following Exercise Interventions

PURPOSE

Nonalcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver diseases in both adults and children with obesity. The aim of this study was to compare the changes in liver enzymes and metabolic profile in adolescents with fatty liver following selected school-based exercise (SBE) and high-intensity interval training (HIIT) interventions.

METHODS

In a semi-experimental study, 34 obese male adolescents with clinically defined NAFLD were divided into the HIIT (n=11, age=12.81±1.02 years, body mass index [BMI]=26.68 ±2.32 kg/m²), selected SBE (n=11, age=13.39±0.95 years, BMI=26.47±1.74 kg/m²), and control (n=12, age=13.14±1.49 years, BMI=26.45±2.21 kg/m²) groups. The ultrasonography NAFLD grade, peak oxygen uptake (VO_2peak), lipid profile, insulin resistance, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels of the participants were measured before and after the exercise interventions.

RESULTS

The BMI, waist-to-hip ratio, and body fat percentage of the participants decreased, and a significant increase in VO_2peak was observed after the intervention; however, the HIIT group showed a significant improvement compared with the SBE group (p<0.01). Significant reductions were observed in the levels of insulin resistance, triglyceride, total cholesterol, ALT, and AST in both groups, although high-density lipoprotein levels decreased only in the HIIT group (p<0.01). Further, a significant reduction in low-density lipoprotein level was observed in the training groups (p<0.01), but this decrease was not significant compared with the control group (p>0.01).

CONCLUSION

HIIT and SBE are equally effective in improving health parameters in obese children and adolescents.

Clinical Value of Information Entropy Compared with Deep Learning for Ultrasound Grading of Hepatic Steatosis

Entropy is a quantitative measure of signal uncertainty and has been widely applied to ultrasound tissue characterization. Ultrasound assessment of hepatic steatosis typically involves a backscattered statistical analysis of signals based on information entropy. Deep learning extracts features for classification without any physical assumptions or considerations in acoustics. In this study, we assessed clinical values of information entropy and deep learning in the grading of hepatic steatosis. A total of 205 participants underwent ultrasound examinations. The image raw data were used for Shannon entropy imaging and for training and testing by the pretrained VGG-16 model, which has been employed for medical data analysis. The entropy imaging and VGG-16 model predictions were compared with histological examinations. The diagnostic performances in grading hepatic steatosis were evaluated using receiver operating characteristic (ROC) curve analysis and the DeLong test. The areas under the ROC curves when using the VGG-16 model to grade mild, moderate, and severe hepatic steatosis were 0.71, 0.75, and 0.88, respectively; those for entropy imaging were 0.68, 0.85, and 0.9, respectively. Ultrasound entropy, which varies with fatty infiltration in the liver, outperformed VGG-16 in identifying participants with moderate or severe hepatic steatosis (p < 0.05). The results indicated that physics-based information entropy for backscattering statistics analysis can be recommended for ultrasound diagnosis of hepatic steatosis, providing not only improved performance in grading but also clinical interpretations of hepatic steatosis.

Predictors of non-alcoholic fatty liver disease (NAFLD) among children with obesity

Background The prevalence of childhood obesity and its related comorbidities in Malaysia are alarming. Malaysia ranked second in childhood obesity among South-east Asian countries with a prevalence of 12.7%. This study was conducted to investigate the prevalence of non-alcoholic fatty liver disease (NAFLD) among obese children and to ascertain the predictors associated with NAFLD. Methods NAFLD was diagnosed via ultrasonographic evidence of fatty liver in obese and overweight children who presented to the Paediatric Obesity Clinic of University Malaya Medical Centre (UMMC), Malaysia. Demographic, anthropometric, clinical and biochemical parameters were analysed and compared between the NAFLD and non-NAFLD groups. Statistical analyses were carried out. Results Twenty-one out of 33 obese and overweight children (63.6%) were found to have NAFLD. We found that 62% of our study population in the NAFLD group had metabolic syndrome based on the definition by the International Diabetes Federation (IDF). Mean body mass index (BMI), waist circumference (WC), triglyceride (TG) and alanine aminotransferase (ALT) were found to be significantly greater in the NAFLD group compared to the non-NAFLD group (35.2 [6.1] vs. 29.3 [4.7] kg/m2 [p-value 0.007]; 104.1 [11.4] vs. 94.1 [12] cm [p-value 0.034]; 1.5 [0.9] vs. 0.9 [0.3] mmol/L [p-value 0.002]; 60.7 [53.8] vs. 27.3 [13] U/L [p-value 0.007]). Multivariate regression analysis revealed TG as the independent predictor for NAFLD, with an odds ratio of 41.7 (95% confidence interval [CI] 0.001, 0.819) (p-value 0.04). Conclusions Prevalence of NAFLD among children who are obese and overweight is alarming with 62% having metabolic syndrome. TG was found to be a strong predictor for NAFLD.

Value of homodyned K distribution in ultrasound parametric imaging of hepatic steatosis: An animal study

Ultrasound is the first-line tool for screening hepatic steatosis. Statistical distributions can be used to model the backscattered signals for liver characterization. The Nakagami distribution is the most frequently adopted model; however, the homodyned K (HK) distribution has received attention due to its link to physical meaning and improved parameter estimation through X- and U-statistics (termed "XU"). To assess hepatic steatosis, we proposed HK parametric imaging based on the α parameter (a measure of the number of scatterers per resolution cell) calculated using the XU estimator. Using a commercial system equipped with a 7-MHz linear array transducer, phantom experiments were performed to suggest an appropriate window size for α imaging using the sliding window technique, which was further applied to measuring the livers of rats (n = 66) with hepatic steatosis induced by feeding the rats a methionine- and choline-deficient diet. The relationships between the α parameter, the stage of hepatic steatosis, and histological features were verified by the correlation coefficient r, one-way analysis of variance, and regression analysis. The phantom results showed that the window side length corresponding to five times the pulse length supported a reliable α imaging. The α parameter showed a promising performance for grading hepatic steatosis (p < 0.05; r² = 0.68). Compared with conventional Nakagami imaging, α parametric imaging provided significant information associated with fat droplet size (p < 0.05; r² = 0.53), enabling further analysis and evaluation of severe hepatic steatosis.

The Role of Lipophagy in the Development and Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) or metabolic (dysfunction) associated liver disease (MAFLD), is, with a global prevalence of 25%, the most common liver disorder worldwide. NAFLD comprises a spectrum of liver disorders ranging from simple steatosis to steatohepatitis, fibrosis, cirrhosis and eventually end-stage liver disease. The cause of NAFLD is multifactorial with genetic susceptibility and an unhealthy lifestyle playing a crucial role in its development. Disrupted hepatic lipid homeostasis resulting in hepatic triglyceride accumulation is an hallmark of NAFLD. This disruption is commonly described based on four pathways concerning 1) increased fatty acid influx, 2) increased de novo lipogenesis, 3) reduced triglyceride secretion, and 4) reduced fatty acid oxidation. More recently, lipophagy has also emerged as pathway affecting NAFLD development and progression. Lipophagy is a form of autophagy (i.e. controlled autolysosomal degradation and recycling of cellular components), that controls the breakdown of lipid droplets in the liver. Here we address the role of hepatic lipid homeostasis in NAFLD and specifically review the current literature on lipophagy, describing its underlying mechanism, its role in pathophysiology and its potential as a therapeutic target.

Obese boys with low concentrations of high-density lipoprotein cholesterol are at greater risk of hepatosteatosis

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) and associated morbidities have become a major public health problem, with a global three-fold increase in incidence among obese children over the last three decades. Although the gold standard for diagnosis of NAFLD is liver biopsy, it is not widely used in children. Imaging techniques, including magnetic resonance imaging (MRI) and ultrasound (US), can provide information on liver fat deposition, however, with variable sensitivity. A number of other predictors are therefore being investigated for pediatric screening and diagnostic purposes. The aim of this study was to assess easily measured parameters to prompt further investigation into NAFLD in obese children.

METHODS

Obese children/adolescents with a body mass index (BMI) percentile > 95 were enrolled in the study (n = 353). After a 12-hour fast, venous glucose, insulin, cholesterol, triglycerides (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and uric acid were measured and a full blood count was performed in all subjects. TG/LDL ratio, AST/platelet ratio index (APRI score), and homeostatic model of assessment for insulin resistance (HOMA-IR) were calculated. All patients underwent an abdominal US examination to assess hepatosteatosis.

RESULTS

Of 353 patients, median age 12.5 (range, 6-17.9) years, 210 patients (59%) had US-proven hepatosteatosis. Female gender reduced the risk of steatosis 2.08-fold (p = 0.005), a one-unit increase in HDL reduced the risk of steatosis 1.02-fold (p = 0.042), and a one-unit increase in BMI led to a 1.11-fold (p = 0.002) increase in the risk of steatosis.

CONCLUSION

Gender, BMI, and HDL were found to be predictors of steatosis. Male patients with low HDL and high BMI are at greater risk of steatosis and should be carefully examined for the presence of NAFLD.

Noninvasive tool for the diagnosis of NAFLD in association with atherosclerotic cardiovascular risk

Background

Whether the severity of liver histology in non-alcoholic fatty liver disease (NAFLD) is associated with more pronounced cardiovascular disease is unsettled. There is a need to develop a noninvasive tool to help its diagnosis in association with atherosclerotic cardiovascular disease. We aimed to evaluate the diagnostic performance of NAFLD-liver fat score (NAFLD-LFS) and carotid intima-media thickness (CIMT) in magnetic resonance imaging-proved NAFLD. The study comprised 60 patients with NAFLD during the period from October 2015 to June 2017, diagnosed by clinical features, laboratory tests, and magnetic resonance study. Thirty healthy subjects served as controls. All included individuals were subjected to anthropometric measurements and measurement of NAFLD-LFS and CIMT.

Results

On doing ultrasonography, 30 cases showed mild, 24 showed moderate, and 6 cases showed severe steatosis. NAFLD-LFS at a cutoff value of − 1.628 showed a sensitivity of 96.7%, specificity 100%, positive predictive value 100%, negative predictive value 93.8%, and accuracy 97.8%. CIMT at a cutoff value of 0.6 had a sensitivity of 70%, specificity 53.3%, positive predictive value 75%, negative predictive value 47.1%, and accuracy 64.4%. The combination of CIMT at cutoff 0.7 and NAFLD-LFS at cutoff − 1.628 showed sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 100%.

Conclusion

CIMT combined with NAFLD-LFS can produce a simple noninvasive tool for diagnosis of NAFLD.

The relationship between nonalcoholic fatty liver disease and pediatric congenital hypothyroidism patients

Previous studies have shown hypothyroidism was independently associated with nonalcoholic fatty liver disease (NAFLD) in adults, but few studies examined their relationships in pediatric populations. This study aimed to investigate the prevalence of NAFLD in pediatric congenital hypothyroidism (CHT) patients and to identify the association between CHT and NAFLD. This study enrolled pediatric CHT patients receiving levothyroxine treatment at one medical center from 2013 to 2014. Euthyroid subjects (ET) and transient hypothyroidism (THT) patients weaned off medication successfully after age 3 were selected for further comparison. Laboratory data including thyroid functions, liver functions, and metabolic profiles were obtained. The major outcome was the occurrence of NAFLD, diagnosed based on the findings of abdominal ultrasonography. One-hundred and twenty-nine subjects (47 in CHT, 47 in THT, and 35 in ET groups) were enrolled. The analysis showed higher fasting serum glucose, insulin, thyroxine (T4), and mean thyroid-stimulating hormone (TSH) levels in the CHT group. NAFLD prevalence was higher in the CHT (23.4%) group than in the THT (8.5%) and the ET (5.7%) groups, demonstrating an increasing trend across three strata (X² _{linear-by-linear} = 5.9, P < .05). The multivariate regression analysis showed obesity (β-coefficient = 5.52, P < .05), CHT (β-coefficient = 2.92, P < .05) and mean TSH levels (β-coefficient = 0.24, P < .05) were independent risk factors for NAFLD. A positive correlation was found between TSH level and lipid profiles. CHT patients had higher risk of NAFLD despite treatment being initiated early in life. Close monitoring of metabolic profiles is warranted. Further research should examine ways to optimize the treatment for CHT patients in terms of prevention against NAFLD.

Nonalcoholic fatty liver disease in obese adolescent females is associated with multi-tissue insulin resistance and visceral adiposity markers

Objective

Nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR) and visceral adiposity in adults and boys, but girls with NAFLD are understudied. We sought to evaluate adipose, liver, and skeletal muscle insulin sensitivity in obese adolescent females with or without hepatic steatosis (HS) (intrahepatic triglyceride (IHTG) content >5.5%) along with cardiometabolic components typically associated with IR.

Study design

73 obese adolescent girls at high risk for NAFLD were enrolled. Participants underwent fasting labs, an MRI to measure IHTG and visceral fat, ³¹phosphorous MR spectroscopy for muscle mitochondrial function, ¹H MR spectroscopy for intramyocellular lipid (IMCL), bicycle ergometry to assess VO₂peak and a 4-phase hyperinsulinemic euglycemic clamp with isotope tracers to measure hepatic and peripheral IR. 29 participants had HS [age 15 yrs(13,16), BMI%ile 98.7(97.4,99.0), IHTG 10.4%(8.0,13.5)] and 44 did not [age 15 yrs(13,17), BMI%ile 98.5(96.2,99.0), IHTG 2.0%(1.1,3.0)].

Results

During hyperinsulinemia, participants with HS vs. non-HS had failure to suppress free fatty acids (p = 0.008), endogenous glucose release (p = 0.002), and a lower glucose metabolic rate of disappearance (Rd) (p = 0.012). Girls with NALFD also had higher visceral fat (p < 0.001), systolic blood pressure (p = 0.026), triglycerides (p = 0.02), ALT (p < 0.01) and white blood cell count (p < 0.01), and lower adiponectin (p = 0.02). There was no difference between girls with and without HS in systemic glycerol turnover measured with glycerol release, or in IMCL, mitochondrial function or VO₂peak.

Conclusions

Obese adolescent girls with HS have evidence of multi-tissue IR, visceral adiposity, inflammation and multiple components of the metabolic syndrome, arguing for close cardiometabolic surveillance over time of girls with HS.

•

We described tissue specific insulin sensitivity in adolescent girls ± NAFLD.

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Girls with NAFLD have higher hepatic and muscular insulin resistance.

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Intramyocellular lipids and muscle mitochondrial function were not different between groups.

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Adipose tissue insulin resistance was not different between groups.

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Girls with NAFLD have worst metabolic profile than those without.

Prevalence of Nonalcoholic Fatty Liver Disease in Children with Obesity

OBJECTIVES

To determine the prevalence of nonalcoholic fatty liver disease (NAFLD) in children with obesity because current estimates range from 1.7% to 85%. A second objective was to evaluate the diagnostic accuracy of alanine aminotransferase (ALT) for NAFLD in children with obesity.

STUDY DESIGN

We evaluated children aged 9-17 years with obesity for the presence of NAFLD. Diseases other than NAFLD were excluded by history and laboratories. Hepatic steatosis was measured by liver magnetic resonance imaging proton density fat fraction. The diagnostic accuracy of ALT for detecting NAFLD was evaluated.

RESULTS

The study included 408 children with obesity that had a mean age of 13.2 years and mean body mass index percentile of 98.0. The study population had a mean ALT of 32 U/L and median hepatic magnetic resonance imaging proton density fat fraction of 3.7%. The estimated prevalence of NAFLD was 26.0% (95% CI 24.2%-27.7%), 29.4% in male patients (CI 26.1%-32.7%) and 22.6% in female patients (CI 16.0%-29.1%). Optimal ALT cut-point was 42 U/L (47.8% sensitivity, 93.2% specificity) for male and 30 U/L (52.1% sensitivity, 88.8% specificity) for female patients. The classification and regression tree model with sex, ALT, and insulin had 80% diagnostic accuracy for NAFLD.

CONCLUSIONS

NAFLD is common in children with obesity, but NAFLD and obesity are not concomitant. In children with obesity, NAFLD is present in nearly one-third of boys and one-fourth of girls.

Hepatic Steatosis Assessment Using Quantitative Ultrasound Parametric Imaging Based on Backscatter Envelope Statistics

Hepatic steatosis is a key manifestation of non-alcoholic fatty liver disease (NAFLD). Early detection of hepatic steatosis is of critical importance. Currently, liver biopsy is the clinical golden standard for hepatic steatosis assessment. However, liver biopsy is invasive and associated with sampling errors. Ultrasound has been recommended as a first-line diagnostic test for the management of NAFLD. However, B-mode ultrasound is qualitative and can be affected by factors including image post-processing parameters. Quantitative ultrasound (QUS) aims to extract quantified acoustic parameters from the ultrasound backscattered signals for ultrasound tissue characterization and can be a complement to conventional B-mode ultrasound. QUS envelope statistics techniques, both statistical model-based and non-model-based, have shown potential for hepatic steatosis characterization. However, a state-of-the-art review of hepatic steatosis assessment using envelope statistics techniques is still lacking. In this paper, envelope statistics-based QUS parametric imaging techniques for characterizing hepatic steatosis are reviewed and discussed. The reviewed ultrasound envelope statistics parametric imaging techniques include acoustic structure quantification imaging, ultrasound Nakagami imaging, homodyned-K imaging, kurtosis imaging, and entropy imaging. Future developments are suggested.

Evaluation of nonalcoholic fatty liver disease using magnetic resonance in obese children and adolescents

OBJECTIVE

To determine the frequency of nonalcoholic fatty liver disease using nuclear magnetic resonance as a noninvasive method.

METHODOLOGY

This was a cross-sectional study conducted on 50 children and adolescents followed up at an outpatient obesity clinic. The subjects were submitted to physical examination, laboratory tests (transaminases, liver function tests, lipid profile, glycemia, and basal insulin) and abdominal nuclear magnetic resonance (calculation of hepatic, visceral, and subcutaneous fat).

RESULTS

Nonalcoholic fatty liver disease was diagnosed in 14 (28%) participants, as a severe condition in eight (percent fat >18%), and as non-severe in four (percent fat from 9% to 18%). Fatty liver was associated with male gender, triglycerides, AST, ALT, AST/ALT ratio, and acanthosis nigricans. Homeostasis model assessment of insulin resistance and metabolic syndrome did not show an association with fatty liver.

CONCLUSION

The frequency of nonalcoholic fatty liver disease in the present population of children and adolescents was lower than that reported in the international literature. It is suggested that nuclear magnetic resonance is an imaging exam that can be applied to children and adolescents, thus representing an effective noninvasive tool for the diagnosis of nonalcoholic fatty liver disease in this age range. However, further national multicenter studies with longitudinal design are needed for a better analysis of the correlation between nonalcoholic fatty liver disease and its risk factors, as well as its consequences.

Reducing NAFLD-screening time: A comparative study of eight diagnostic methods offering an alternative to ultrasound scans

BACKGROUND & AIMS

The use of ultrasound scan (US) in non-alcoholic fatty liver disease (NAFLD) screening overloads US waiting lists. We hypothesized and tested a hybrid two-step method, consisting of applying a formula, to exclude subjects at low risk, before US.

METHODS

The sample included 2970 males and females (937 with NAFLD) diagnosed by US. We selected eight formulas: Fatty Liver Index (FLI), Hepatic Steatosis Index (HIS), body mass index (BMI), waist circumference (WC), Abdominal Volume Index (AVI), waist-to-height ratio (WHtR), waist/height^0.5 (WHT.5R) and Body Roundness Index (BRI), and calculated their performance in the two-step method evaluating percentage reduction of the number of liver US (US reduction percentage), percentage of false negative and percentage of NAFLD identified.

RESULTS

The US reductions percentage were 52.2% (WHtR), 52.1% (HIS), 51.8% (FLI), 50.8% (BRI), 50.7% (BMI and WHt_5R), 46.5% (WC) and 45.2% (AVI). The false negative percentage were 8.5% (WHtR), 7.9% (BRI), 7.3% (WHt_5R), 7.2% (BMI), 6.7% (HIS), 6.6% (FLI), 5.6% (WC) and 5.2% (AVI). The best percentage of NALFD identified was obtained using AVI (83.6%) before US, then WC (82.2%), FLI (79%), HIS (78.9%), BMI (77.3%), WHt_5R (76.9%), BRI (74.8%) and WHtR (73%).

CONCLUSION

The best formula to use in two-step diagnostic NAFLD screening was AVI, which showed a low false negative rate and a higher percentage of identified NAFLD. Other studies evaluating the economic advantages of this screening method are warranted.

Liver Fat Content and Body Fat Distribution in Youths with Excess Adiposity

This study had two main objectives: To examine the association between body fat distribution and non-alcoholic fatty liver disease (NAFLD) and liver fat content, and to determine whether the relationship between NAFLD and regional body fat distribution, with respect to liver fat content in youths with excess adiposity, is independent of cardiorespiratory fitness (CRF) and a healthy diet. Liver fat content (controlled attenuation parameter (CAP)), body fat distribution (body mass index (BMI) z-score, waist circumference, waist-to-height ratio, fat mass/height, body fat percentage, total fat mass, android-to-gynoid fat mass ratio, visceral adipose tissue (VAT), and lean mass index, determined by dual-energy X-ray absorptiometry (DXA)), CRF (20-m shuttle-run test), and healthy diet (adherence to the Mediterranean diet by KIDMED questionnaire) were measured in 126 adolescents (66% girls) aged between 11 and 17 years. Participants were assigned to two groups according to the presence or absence of hepatic steatosis (CAP values ≥225 dB/m or <225 dB/m of liver fat, respectively). Considering the similar total fat values for the two groups (>30% by DXA), youths with NAFLD had higher fat distribution parameters than those without NAFLD, regardless of sex, age, puberty stage, lean mass index, CRF, and healthy diet (p < 0.01). In the non-NAFLD group, the association between hepatic fat and fat distribution parameters presented a similar pattern, although the association was statistically insignificant after adjusting for a potential confounding variable (ps > 0.05), except for the case of VAT. Body fat distribution parameters were higher in youths with NAFLD compared to those without NAFLD. Additionally, body fat distribution showed a significant association with liver fat content as assessed by CAP in youths with NAFLD independent of CRF and adherence to the Mediterranean diet, supporting the notion that upper body fat distribution might play a pivotal role in the development of NAFLD in adolescents. These results may have implications for the clinical management of youths with excess adiposity given the high prevalence of NAFLD in children and young adults.

Genetic determinants of hepatic steatosis and serum cytokeratin-18 fragment levels in Taiwanese children

BACKGROUND/AIMS

There are substantial genetic components contributing to the susceptibility of nonalcoholic fatty liver disease (NAFLD). It has recently been reported that the rs641738 C>T variant in the membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) gene increased severity of NAFLD in adults of European descent. We aimed to test the hypothesis that MBOAT7 rs641738 variant would increase hepatic steatosis and hepatocellular injury in obese children.

METHODS

A total of 831 obese children aged 7-15 years were recruited. Hepatic steatosis was measured by ultrasonography. Because PNPLA3 rs738409, GCKR rs780094 and TM6SF2 rs58542926 variants are known to confer susceptibility to NAFLD, we assessed the influence of MBOAT7 rs641738 on hepatic steatosis, and serum levels of CK-18 fragment (a biomarker of hepatocellular injury and apoptosis for NAFLD) after adjusting the effects of PNPLA3, GCKR and TM6SF2 polymorphisms.

RESULTS

Of the recruited obese children, 22.7% had hepatic steatosis. PNPLA3 rs738409, GCKR rs780094 and TM6SF2 rs58542926 variants were independent risk factors of hepatic steatosis and elevated ALT levels. In contrast, MBOAT7 rs641738 variants, neither heterozygous nor homozygous genotypes, were not associated with hepatic steatosis, insulin resistance, lipid levels and liver enzymes. The multiple linear regression model revealed that after adjusting for age, gender, body mass index z score, PNPLA3 rs738409 and GCKR rs780094 variants, but not MBOAT7 rs641738, were associated with serum levels of CK-18 fragment.

CONCLUSIONS

The variant MBOAT7 rs641738 genotype is not associated with hepatic steatosis and serum levels of CK-18 fragment in obese Taiwanese children.

p53 as a Dichotomous Regulator of Liver Disease: The Dose Makes the Medicine

Lifestyle-related disorders, such as the metabolic syndrome, have become a primary risk factor for the development of liver pathologies that can progress from hepatic steatosis, hepatic insulin resistance, steatohepatitis, fibrosis and cirrhosis, to the most severe condition of hepatocellular carcinoma (HCC). While the prevalence of liver pathologies is steadily increasing in modern societies, there are currently no approved drugs other than chemotherapeutic intervention in late stage HCC. Hence, there is a pressing need to identify and investigate causative molecular pathways that can yield new therapeutic avenues. The transcription factor p53 is well established as a tumor suppressor and has recently been described as a central metabolic player both in physiological and pathological settings. Given that liver is a dynamic tissue with direct exposition to ingested nutrients, hepatic p53, by integrating cellular stress response, metabolism and cell cycle regulation, has emerged as an important regulator of liver homeostasis and dysfunction. The underlying evidence is reviewed herein, with a focus on clinical data and animal studies that highlight a direct influence of p53 activity on different stages of liver diseases. Based on current literature showing that activation of p53 signaling can either attenuate or fuel liver disease, we herein discuss the hypothesis that, while hyper-activation or loss of function can cause disease, moderate induction of hepatic p53 within physiological margins could be beneficial in the prevention and treatment of liver pathologies. Hence, stimuli that lead to a moderate and temporary p53 activation could present new therapeutic approaches through several entry points in the cascade from hepatic steatosis to HCC.

Circulating levels of miR-122 and nonalcoholic fatty liver disease in pre-pubertal obese children

OBJECTIVES

The liver-specific miR-122 was proposed as biomarker for NAFLD in adults. Here, we investigated the relationship between miR-122 levels, parameters of liver metabolism and NAFLD in pre-pubertal obese children.

METHODS

Parameters of liver metabolism (ALT, AST and GGT) of three European cohorts were included (German cohort [n = 71; age: 11.53 ± 1.29 years; BMI z-score: 2.96 ± 0.64], Italian cohort [n = 45; age: 9.60 ± 2.11 years; BMI z-score: 3.57 ± 1.16], Slovenian cohort [n = 31; age: 7.53 ± 1.47 years; BMI z-score: 3.66 ± 0.88]). MiR-122 levels and CK18 concentrations were measured in fasting blood samples. In the German and Italian cohort, the diagnosis of NAFLD and grading of NAFLD was assessed by ultrasound.

RESULTS

NAFLD was diagnosed in n = 50 patients of the German cohort (29.6%) and in n = 29 patients (72.5%) of the Italian cohort. In all three cohorts, miR-122 was positively correlated with ALT and AST as well as with CK18 concentrations. MiR-122 levels were higher in children with NAFLD compared with healthy controls.

CONCLUSIONS

MiR-122 levels in pre-pubertal obese children could be a potential biomarker for paediatric NAFLD.

Dietitian-led lifestyle modification programme for obese Chinese adolescents with non-alcoholic fatty liver disease: a randomized controlled study

BACKGROUND

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is increasing. This study evaluated the efficacy of a dietitian-led lifestyle modification programme (D-LMP) to reduce NAFLD in obese adolescents.

METHODS

Subjects with intra-hepatic triglyceride content (IHTC) equal to or greater than 5% diagnosed by proton-magnetic resonance spectroscopy (¹H-MRS) were enroled and randomly assigned to either the D-LMP intervention or conventional paediatrician-led consultation (P-CON) group. Subjects in the P-CON group received usual care consisting of a consultation by a paediatrician with the child and parents every 16 weeks. Intention-to-treat analysis was used for data analysis.

RESULTS

Fifty-two subjects were recruited, with 26 in each group. After the initiation phase (at week-16), there was a greater difference in the change in the IHTC and BMI z-score in the D-LMP group (P = 0.029 and <0.001, respectively) and there was a decrease in dietary intake of fat content (P = 0.019). After 52 weeks of the maintenance phase, both groups had reductions of IHTC to 2-3% and there was no intergroup difference in the rate of reduction. During the maintenance phase, parents' involvement was minimal in the D-LMP group, with only three parents accompanying their children to attend the dietitian sessions. In contrast, over 90% of the parents in the P-CON group regularly accompanied their children to attend the consultations suggesting the possibility that regular parental and paediatrician involvement may contribute to increasing awareness on fatty liver complications. Multivariate analysis showed that only reduction in body fat remained as an independent factor associated with remission of NAFLD at the end of both study phases.

CONCLUSIONS

A dietitian-led lifestyle modification intervention reduced IHTC, BMI z-score and body fat in obese Chinese adolescents with NAFLD. To sustain the effect of this intervention, regular parental and paediatrician involvement may be important.

Elevation of circulating microRNA levels in obese children compared to healthy controls

As childhood obesity increases, it is becoming important to understand the complications of obesity in children and develop novel biomarkers. Evidence indicates that microRNAs (miRNA) are dys-regulated in obesity and may serve as sensitive and specific circulating biomarkers. Non-alcoholic fatty liver disease (NAFLD) is a complication of obesity that ultimately requires a liver biopsy to determine disease severity. While studies have been conducted in adults, no study to date has examined circulating miRNAs in children with obesity and NAFLD. The goal of this study was to evaluate a panel of selected circulating miRNAs in obese children compared to healthy controls. We present here an analysis of a pre-selected panel of 20 candidate miRNAs in obese children compared to healthy controls. The miRNAs were chosen based on having been previously reported to be involved in NAFLD. We found that 16 out of 20 miRNAs tested were elevated at least twofold in children with obesity compared to controls. miR-122 and miR-199a showed the greatest increase in children with obesity versus controls. Both also had a high area under the curve when receiver-operator curves were plotted. Several circulating miRNAs correlated with body mass index (BMI) or serum transaminases. This study provides initial evidence that circulating miRNAs can be measured in the paediatric population and provides several diagnostic candidates increased in children with obesity that may be relevant to NAFLD.

Serum Alanine Aminotransferase Trends and Their Relationship with Obesity and Metabolic Syndrome in United States Adolescents, 1999-2014

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD), characterized by hepatocyte dysfunction, fat accumulation, and fibrosis, is the most common cause of chronic liver disease in children. Elevated levels of serum alanine aminotransferase (ALT) are used clinically to identify potential liver dysfunction. Our goal was to assess for changes in the national prevalence of elevated ALT over time and potential relationship to trends in the metabolic syndrome (MetS) severity and elevated body mass index (BMI).

MATERIALS AND METHODS

We studied 5411 non-Hispanic white, non-Hispanic black, and Hispanic adolescents aged 12-19 with complete MetS Z-score and ALT data from the National Health and Nutrition Examination Survey 1999-2014. Elevated ALT levels were defined by two different cutoffs: one for both sexes (30 U/L) and another that was sex specific (22 U/L girls; 25 U/L boys). MetS severity was assessed using a sex- and race-/ethnicity-specific MetS Z-score.

RESULTS

We did not find a statistically significant linear increase in either mean ALT or the prevalence of elevated ALT differed over time. As expected, ALT levels were significantly correlated with BMI Z-score and MetS Z-score (P < 0.0001). Over time, BMI Z-scores increased and MetS severity Z-score decreased.

CONCLUSION

Prevalence of elevated ALT did not exhibit a linear change between 1999 and 2014 in U.S. adolescents, potentially due to divergent trends regarding BMI and MetS severity. Continued vigilance in monitoring BMI and ALT levels is advised for the U.S. adolescent population. MetS Z-score could act as an additional tool to monitor risk of elevated ALT and subsequent development of NAFLD.

Effect of ultrasound frequency on the Nakagami statistics of human liver tissues

The analysis of the backscattered statistics using the Nakagami parameter is an emerging ultrasound technique for assessing hepatic steatosis and fibrosis. Previous studies indicated that the echo amplitude distribution of a normal liver follows the Rayleigh distribution (the Nakagami parameter m is close to 1). However, using different frequencies may change the backscattered statistics of normal livers. This study explored the frequency dependence of the backscattered statistics in human livers and then discussed the sources of ultrasound scattering in the liver. A total of 30 healthy participants were enrolled to undergo a standard care ultrasound examination on the liver, which is a natural model containing diffuse and coherent scatterers. The liver of each volunteer was scanned from the right intercostal view to obtain image raw data at different central frequencies ranging from 2 to 3.5 MHz. Phantoms with diffuse scatterers only were also made to perform ultrasound scanning using the same protocol for comparisons with clinical data. The Nakagami parameter-frequency correlation was evaluated using Pearson correlation analysis. The median and interquartile range of the Nakagami parameter obtained from livers was 1.00 (0.98-1.05) for 2 MHz, 0.93 (0.89-0.98) for 2.3 MHz, 0.87 (0.84-0.92) for 2.5 MHz, 0.82 (0.77-0.88) for 3.3 MHz, and 0.81 (0.76-0.88) for 3.5 MHz. The Nakagami parameter decreased with the increasing central frequency (r = -0.67, p < 0.0001). However, the effect of ultrasound frequency on the statistical distribution of the backscattered envelopes was not found in the phantom results (r = -0.147, p = 0.0727). The current results demonstrated that the backscattered statistics of normal livers is frequency-dependent. Moreover, the coherent scatterers may be the primary factor to dominate the frequency dependence of the backscattered statistics in a liver.

Prevalence and risk factors for non-alcoholic fatty liver in children and youth with obesity

Background

Non- Alcoholic Fatty Liver (NAFL) is a spectrum of liver diseases (LD) that ranges from benign fatty infiltration of the liver to cirrhosis and hepatic failure. Hepatic ultrasound (US) and serum alanine aminotransferase (ALT) are often used as markers of NAFL. Our aim is to describe prevalence of NAFL and associated findings on ultrasound (US) and biochemical parameters in a population of children and adolescents with obesity at the Children’s Hospital of Eastern Ontario.

Methods

Children with Obesity (BMI >95th percentile) ages 8–17 years presenting to the Endocrinology and Gastroenterology clinics, without underlying LD were prospectively recruited from 2009 to 2012. Fasting lipid profile, HOMA IR) and serum adiponectin levels were measured. NAFL was defined as ALT > 25 and >22 IU/mL (males and females respectively) and/or evidence of fatty infiltration by US. Logistic regression was performed to assess associations.

Results

97 children with obesity included in the study (Male 43%). Mean age was 12.9 ± 3.2 years (84% were older than 10 y). Mean BMI-Z score was 3.8 ± 1.4. NAFL was identified in 85%(82/97) of participants. ALT was elevated in 61% of patients. Median triglyceride (TG) level was higher in children with NAFL(1.5 ± 0.9 vs. 1.1 ± 0.5 mmol/L, p = 0.01). Total cholesterol, HDL, LDL and Non HDL cholesterol were similar in both groups(p = 0.63, p = 0.98, p = 0.72 and p = 0.37 respectively). HOMA IR was ≥3.16 in 53% of children(55% in those with NAFL and 40% in those without NAFL). Median serum adiponectin was 11.2 μg/ml(IQR 7.3–18.3) in children with NAFL vs. 16.1 μg/ml(IQR 9.0–21.9) in those without NAFL(p = 0.23). Liver US was reported as normal in 30%, mild fatty infiltration in 38%, moderate in 20% and severe in 12%. TG were significantly higher(1.5 mmol/L vs. 1.0 mmol/L, p < 0.01) and HDL-C was lower(1.0 mmol/L vs. 1.1 mmol/L, p = 0.05) in children with moderate and severe NAFL by US. BMI-Z score, HOMA IR, serum adiponectin and HDL levels were not associated with NAFL, however TG were significantly associated(OR = 3.22 (95% CI: 1.01–10.25, p = 0.04)).

Conclusion

NAFL is highly prevalent in obese children and youth. Elevated TG levels are associated with NAFL; these findings may serve as a noninvasive screening tool to help clinicians identify children with obesity needing liver biopsy and/or more aggressive therapeutic interventions.

Features of nonalcoholic steatohepatitis in severely obese children and adolescents undergoing sleeve gastrectomy

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is an underrecognized co-morbidity of obesity. The characteristic features and severity of NAFLD in severe childhood obesity remain unknown.

OBJECTIVES

To investigate features of NAFLD in obese children and identify predictors of significant disease.

SETTING

Academic center with a standardized pathway for pediatric bariatric surgery and a dedicated multidisciplinary team.

DESIGN

This is a baseline cross-sectional analysis for a data set obtained from a prospective clinical outcome study that included severely obese children (≤14 yr of age) and adolescents (14-21 yr of age) who underwent laparoscopic sleeve gastrectomy between March 2008 and March 2015. Patients with syndromic obesity, history of alcohol intake, parenteral nutrition, liver disease, intake of medications that may affect NAFLD and weight, and insufficient tissue biopsy were excluded. Prevalence and features of nonalcoholic steatohepatitis (NASH) and clinically significant liver fibrosis in different pediatric age groups and noninvasive predictors in severe childhood obesity were evaluated.

RESULTS

The 296 patients in the study group (1:1 sex distribution) had a mean body mass index and age of 48.4±9.8 kg/m² and 14.5±3.6 years, respectively. According to histopathology assessment, 225 (76%) patients had NAFLD, of whom 118 patients (39.9% of the total cohort) had NASH. Additionally, 110 (37.2%) had clinically significant (stage 2+) fibrosis and 256 (86.5%) had portal inflammation. Those with NASH were younger than those without NASH (P = .02; prevalence of NASH in children aged≤10 yr = 64.9%) and were more likely to be male (P = .003). Of children aged≤10 years, 60% had clinically significant fibrosis compared with 32% of older patients (P = .03). High-density lipoproteins, triglycerides, glycated hemoglobin, alanine transaminase, and systolic and diastolic blood pressure levels were most predictive of fibrosis. For NASH, triglycerides, homeostatic model assessment of insulin resistance, glycated hemoglobin, alkaline phosphatase, aspartate transaminase, and alanine transaminase were most predictive.

CONCLUSIONS

In our setting, 65% of severely obese young children had NASH, and 60% had clinically significant liver fibrosis. Young age, male sex, and features of metabolic syndrome were significantly associated with NASH and liver fibrosis in severely obese pediatric patients.

Variants in the autophagy-related gene IRGM confer susceptibility to non-alcoholic fatty liver disease by modulating lipophagy

BACKGROUND & AIMS

Autophagy has been shown to be crucial in the regulation of the intracellular lipid stores in hepatocytes. We hypothesize that immunity-related GTPase family M (IRGM) gene (an autophagy-related gene) variants confer the susceptibility to non-alcoholic fatty liver disease (NAFLD) development.

METHODS

832 obese children and adolescents aged 6-18years were recruited. NAFLD was determined by liver ultrasonography. We genotyped PNPLA3 rs738409, GCKR rs780094, TM6SF2 rs58542926, six IRGM single nucleotide polymorphisms (rs13361189, rs9637876, rs72553867, rs10065172, rs1000113, and rs11747270). To understand the molecular mechanism, we examined the effects of IRGM knockdown and overexpression on autophagic flux and lipid droplet metabolism in human hepatoma cells.

RESULTS

22.8% of recruited obese children and adolescents had NAFLD. Multiple logistic regression analysis revealed that after controlling for the effects of age- and gender-adjusted body mass index, gender, PNPLA3, GCKR, and TM6SF2 polymorphisms, variant IRGM rs10065172 TT genotype independently increased the odds ratio of NAFLD by 2.04 (95% confidence interval 1.22-3.42; p=0.007), as compared to the CC genotype. The predictive model was validated by means of 10-fold cross validation. Functional assay revealed that IRGM knockdown inhibited autophagic flux and increased lipid droplet content in HepG2 and PLC/PRF/5 cells, which were reversed by the autophagy inducer rapamycin administration. Similarly, wortmannin (an autophagy inhibitor) increased intracellular lipid droplet content. In contrast, overexpression of IRGM caused decreased lipid droplet content in HepG2 cells.

CONCLUSIONS

Our findings suggest that IRGM may contribute to the development of human NAFLD by altering hepatic lipid metabolism through the autophagy pathway.

LAY SUMMARY

Autophagy is involved in the process of lipid metabolism in hepatocytes. The mechanism of autophagy regulation by IRGM has just been unveiled. This study demonstrates that genetic variants in IRGM confer risk of human non-alcoholic fatty liver disease. The functional studies reveal how IRGM regulates hepatic lipid droplet content.

Clinical significance of serum alanine aminotransferase and lifestyle intervention in children with nonalcoholic fatty liver disease

Purpose

This study aimed to investigate the clinical significance of serum alanine aminotransferase (ALT) levels in children with nonalcoholic fatty liver disease (NAFLD) and the effect of lifestyle intervention on NAFLD.

Methods

The clinical data of 86 children diagnosed with NAFLD were reviewed retrospectively. Forty-six patients belonged to the elevated ALT group and 40 to the normal ALT group. The clinical parameters of patients with NAFLD were also compared based on the status of ALT levels after lifestyle intervention.

Results

Patients with elevated ALT had significantly higher body mass index (BMI) scores than those with normal ALT (P<0.05). Of all the patients with elevated ALT, 89% exhibited moderate or severe degree of fatty change in the liver on ultrasonographic examination, whereas most patients with normal ALT exhibited mild or moderate degree changes. Liver biopsy was performed in 15 children with elevated ALT and all showed mild histological changes. Of all patients with elevated ALT, 49% achieved normal ALT levels after lifestyle intervention. Those with more severe histological changes tended to have continuously increasing ALT levels. There was no correlation between the normalization of posttreatment ALT level and BMI, as well as ultrasonographic findings at diagnosis.

Conclusion

ALT elevation in NAFLD is highly associated with higher BMI scores and more severe degree of fatty changes on ultrasonographic examination. Lifestyle intervention can significantly improve ALT in children with NAFLD. The degree of histologic changes appears to be a predictor of the treatment response to NAFLD.

Prediction and Diagnosis of Non-Alcoholic Fatty Liver Disease (NAFLD) and Identification of Its Associated Factors Using the Classification Tree Method

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease in many parts of the world.

Objectives

The aim of the present study was to identify the most important factors influencing NAFLD using a classification tree (CT) to predict the probability of NAFLD.

Patients and Methods

This cross-sectional study was conducted in Kavar, a town in the south of Fars province, Iran. A total of 1,600 individuals were selected for the study via the stratified method and multiple-stage cluster random sampling. A total of 30 demographic and clinical variables were measured for each individual. Participants were divided into two datasets: testing and training. We used the training dataset (1,120 individuals) to build the CT and the testing dataset (480 individuals) to assess the CT. The CT was also used to estimate class and to predict fatty liver occurrence.

Results

NAFLD was diagnosed in 22% of the individuals in the sample. Our findings revealed that the following variables, based on univariate analysis, had a significant association with NAFLD: marital status, history of hepatitis B vaccine, history of surgery, body mass index (BMI), waist-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-density lipoprotein (HDL), triglycerides (TG), alanine aminotransferase (ALT), cholesterol (CHO0, aspartate aminotransferase (AST), glucose (GLU), albumin (AL), and age (P < 0.05). The main affecting variables for predicting NAFLD based on the CT and in order of importance were as follows: BMI, WHR, triglycerides, glucose, SBP, and alanine aminotransferase. The goodness of fit model based on the training and testing datasets were as follows: prediction accuracy (80%, 75%), sensitivity (74%, 73%), specificity (83%, 77%), and the area under the receiver operating characteristic (ROC) curve (78%, 75%), respectively.

Conclusions

The CT is a suitable and easy-to-interpret approach for decision-making and predicting NAFLD.

Relationship between Neck Circumference and Non-Alcoholic Fatty Liver Disease in Childhood Obesity

OBJECTIVE

The aim of this study was to establish the association between anthropometric parameters and non-alcoholic fatty liver disease (NAFLD) and to determine the most reliable measurement as a parameter in predicting NAFLD.

METHODS

Two-hundred fifty-three obese children of ages 10 to 18 years were enrolled in this study. Anthropometric data and metabolic parameters such as fasting blood glucose, insulin and lipid levels, were measured. Liver function tests were assessed. NAFLD was determined by ultrasound.

RESULTS

Most metabolic parameters and anthropometric indices were significantly higher in children with NAFLD. A univariate logistic regression analysis was performed, taking NAFLD status as the dependent variable and anthropometric parameters as the independent variables. NAFLD was affected significantly by the anthropometric values. The multiple logistic regression analysis showed that neck circumference (NC) was the only parameter which determined the risk in both genders. Each 1 cm increase in the NC increased the risk of NAFLD 1.544-fold (p<0.001, 95% confidence interval (CI): 1.357-2.214) in the boys and 1.733-fold (p=0.001, 95% CI: 1.185-2.012) in the girls. Receiver operating characteristic analysis was performed to compare the reliability of anthropometric measurements. NC was observed to be a better indicator.

CONCLUSION

Measurement of the NC was shown to be associated with NAFLD in children. We suggest the use of NC as a novel, simple, practical, and reliable anthropometric index in predicting children at risk for NAFLD.

Anthropometric Indices in Adults: Which Is the Best Indicator to Identify Alanine Aminotransferase Levels?

BACKGROUND

To evaluate the correlations between serum alanine aminotransferase (ALT) levels and anthropometric indices including body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), and a new body index, the A Body Shape Index (ABSI) in Chinese adults.

METHODS

A multicenter, cross-sectional study was conducted in rural areas of China in 2012-2013, and 11,331 adults were included in our final analysis.

RESULTS

BMI, WC, HC, WHtR, WHR and ABSI were significantly positively correlated with ALT levels. Spearman rank test showed that WHtR (r = 0.346 for men, r = 0.282 for women, both p < 0.001) had the highest correlation coefficient for ALT level, whereas ABSI showed the lowest, and the correlation coefficient of each measure was higher in men than that in women. Comparing the lowest with the highest quintile of each anthropometric measure, the multivariate logistic model presented that WHtR had the superiority of identifying the presence of elevated ALT (OR 4.38; 95% CI 3.15-6.08 for men, OR 4.29; 95% CI 2.91-6.33 for women, both p < 0.001), and the ABSI was the poorest predictor in men (OR 2.51; 95% CI 1.93-3.27, p < 0.001). No association was observed for ABSI in women.

CONCLUSIONS

Our results indicated that BMI, WC, HC, WHtR and WHR were able to determine elevated ALT presence, while ABSI was not capable. WHtR and to some extent BMI were the best body indices, for predicting the ALT levels in this population. Nevertheless, the predictive ability of ABSI as a novel body index was not superior compared to established anthropometric indices.