Diagnosis of nonalcoholic fatty liver disease in children and adolescents: position paper of the ESPGHAN Hepatology Committee

Prevalence of increased transaminases and its association with sex, age, and metabolic parameters in children and adolescents with obesity - a nationwide cross-sectional cohort study

Background

Childhood obesity increases the risk of non-alcoholic fatty liver disease marked by elevated alanine aminotransferase (ALT). This study investigated the prevalence of increased ALT in children and adolescents with obesity, and its associations with sex, age, degree of obesity, and metabolic parameters.

Methods

Individuals between 5 and 17.99 years of age enrolled in the Swedish Childhood Obesity Treatment Register (BORIS) before March 2020 were included. Mildly increased ALT was defined by ALT 27–51 U/L (males) and 23–43 U/L (females), while markedly increased ALT by levels above. Multiple logistic regression models were used for statistical analysis.

Results

Among 11,776 individuals (age 11.0 ± 3.3 years, 53.5% males), the prevalence of mildly and markedly increased ALT were 37.9 and 10.6%, respectively. A sex-age interaction was found, where increasing age strengthened the odds of markedly increased ALT in males (OR, 99% CI: 1.34, 1.29–1.4 for each year) while the corresponding pattern in females with was minuscule (1.09, 1.02–1.10). Compared to class I obesity, class II and III obesity had greater odds ratios for mildly increased ALT (class II obesity OR, 99% CI: 1.51, 1.35–1.70; class III obesity OR, 99% CI: 2.17, 1.66–2.61) and for markedly increased ALT (class II obesity OR, 99% CI: 1.82, 1.51–2.20; class III obesity OR, 99% CI 3.38, 2.71–4.23). Dyslipidemia was associated with both mildly and markedly increased ALT, all p < 0.001. Prevalence of impaired fasting glucose was 19.1% in normal ALT group, 20.4% in mildly increased ALT group, and 29.0% in markedly increased ALT group.

Conclusions

The risk of markedly increased ALT increased exponentially with age among boys, but not among girls. Higher degree of obesity was observed in individuals with mildly and markedly increased ALT. Further, metabolic derangements were more prevalent among individuals with mildly and markedly increased ALT.

Diagnosis and management of secondary causes of steatohepatitis

The term non-alcoholic fatty liver disease (NAFLD) was originally coined to describe hepatic fat deposition as part of the metabolic syndrome. However, a variety of rare hereditary liver and metabolic diseases, intestinal diseases, endocrine disorders and drugs may underlie, mimic, or aggravate NAFLD. In contrast to primary NAFLD, therapeutic interventions are available for many secondary causes of NAFLD. Accordingly, secondary causes of fatty liver disease should be considered during the diagnostic workup of patients with fatty liver disease, and treatment of the underlying disease should be started to halt disease progression. Common genetic variants in several genes involved in lipid handling and metabolism modulate the risk of progression from steatosis to fibrosis, cirrhosis and hepatocellular carcinoma development in NAFLD, alcohol-related liver disease and viral hepatitis. Hence, we speculate that genotyping of common risk variants for liver disease progression may be equally useful to gauge the likelihood of developing advanced liver disease in patients with secondary fatty liver disease.

Association between MBOAT7 rs641738 polymorphism and non-alcoholic fatty liver in overweight or obese children

BACKGROUND AND AIM

The association between non-alcoholic fatty liver (NAFL) and the variant rs641738 within the membrane bound O-acyltransferase domain-containing 7 (MBOAT7) gene is currently uncertain, especially in the paediatric population. We examined whether there is an association between this genetic variant and NAFL in a large multicentre, hospital-based cohort of Italian overweight/obese children.

METHODS AND RESULTS

We studied 1760 overweight or obese children [mean age (SD): 11.1(2.9) years, z-body mass index (zBMI) 3.2(0.9)], who underwent ultrasonography for the diagnosis of NAFL. A subgroup of these children (n = 182) also underwent liver biopsy. Genotyping of the MBOAT7 rs641738 polymorphism was performed by TaqMan-Based RT-PCR system in each subject. Overall, 1131 (64.3%) children had ultrasound-detected NAFL; 528 (30%) had rs641738 CC genotype, 849 (48.2%) had rs641738 CT genotype, and 383 (21.8%) had rs641738 TT genotype, respectively. In the whole cohort, the interaction of MBOAT7 genotypes with zBMI was not associated with NAFL after adjustment for age, sex, serum triglycerides, serum alanine aminotransferase levels and patatin-like phospholipase domain-containing protein-3 (PNPLA3) genotype (adjusted-odds ratio 1.02 [95% CI 0.98-1.06]). Similarly, no association was found between MBOAT7 genotypes and NAFL after stratification by obesity status. MBOAT7 genotypes were not associated with the presence of non-alcoholic steatohepatitis or the stage of liver fibrosis in a subgroup of 182 children with biopsy-proven NAFLD.

CONCLUSIONS

The results of this study did not show any significant contribution of MBOAT7 rs641738 polymorphism to the risk of having either NAFL on ultrasonography or NASH on histology in a large hospital-based cohort of Italian overweight/obese children.

Non-Alcoholic Fatty Liver Disease in Obese Youth With Insulin Resistance and Type 2 Diabetes

Currently, Non-Alcoholic Fatty Liver Disease (NAFLD) is the most prevalent form of chronic liver disease in children and adolescents worldwide. Simultaneously to the epidemic spreading of childhood obesity, the rate of affected young has dramatically increased in the last decades with an estimated prevalence of NAFLD of 3%-10% in pediatric subjects in the world. The continuous improvement in NAFLD knowledge has significantly defined several risk factors associated to the natural history of this complex liver alteration. Among them, Insulin Resistance (IR) is certainly one of the main features. As well, not surprisingly, abnormal glucose tolerance (prediabetes and diabetes) is highly prevalent among children/adolescents with biopsy-proven NAFLD. In addition, other factors such as genetic, ethnicity, gender, age, puberty and lifestyle might affect the development and progression of hepatic alterations. However, available data are still lacking to confirm whether IR is a risk factor or a consequence of hepatic steatosis. There is also evidence that NAFLD is the hepatic manifestation of Metabolic Syndrome (MetS). In fact, NAFLD often coexist with central obesity, impaired glucose tolerance, dyslipidemia, and hypertension, which represent the main features of MetS. In this Review, main aspects of the natural history and risk factors of the disease are summarized in children and adolescents. In addition, the most relevant scientific evidence about the association between NAFLD and metabolic dysregulation, focusing on clinical, pathogenetic, and histological implication will be provided with some focuses on the main treatment options.

Development and Internal Validation of Fatty Liver Prediction Models in Obese Children and Adolescents

To develop predictive models of fatty liver (FL), we performed a cross-sectional retrospective study of 1672 obese children with a median (interquartile range) age of 15 (13-16) years. The outcome variable was FL diagnosed by ultrasonography. The potential predictors were: (1) binary: sex; (2) continuous: age, body mass index (BMI), waist circumference (WC), alanine transaminase (ALT), aspartate transaminase, gamma-glutamyltransferase, glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), HDL-cholesterol, LDL-cholesterol, triglycerides, mean arterial pressure, uric acid, and c-reactive protein; (3) ordinal: Pubertal status. Bootstrapped multivariable logistic regression with fractional polynomials was used to develop the models. Two models were developed and internally validated, one using BMI and the other using WC as the anthropometric predictor. Both models included ALT, HOMA-IR, triglycerides, and uric acid as predictors, had similar discrimination (c-statistic = 0.81), and were similarly well calibrated as determined by calibration plots. These models should undergo external validation before being employed in clinical or research practice.

Non-alcoholic fatty liver disease and lipotoxicity

Non-alcoholic fatty liver disease (NAFLD) has become the most common liver pathology worldwide due to the rising prevalence of obesity. This term includes changes from simple steatosis to steatohepatitis and fibrosis. It was previously thought to be a hepatic manifestation of metabolic syndrome, but recent literature describes this relation as much more complex and bi-directional. Development of NAFLD is associated with other metabolic syndrome components but it can also exacerbate insulin resistance and increase cardiovascular risk. Recently a lot of attention is brought to the role of lipids and lipotoxicity in pathogenesis and progression of non-alcoholic fatty disease. It seems that some lipid classes can be protective against liver injury while others are harmful in excessive amounts. This study presents an overview of the main lipids involved in the pathogenesis of non-alcoholic fatty liver disease and summarizes their association with lipotoxicity, insulin resistance, oxidative stress and other processes responsible for its progression.

The Evaluation of Drug Delivery Nanocarrier Development and Pharmacological Briefing for Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Current research indicates that the next silent epidemic will be linked to chronic liver diseases, specifically non-alcoholic fatty liver disease (NAFLD), which was renamed as metabolic-associated fatty liver disease (MAFLD) in 2020. Globally, MAFLD mortality is on the rise. The etiology of MAFLD is multifactorial and still incompletely understood, but includes the accumulation of intrahepatic lipids, alterations in energy metabolism, insulin resistance, and inflammatory processes. The available MAFLD treatment, therefore, relies on improving the patient's lifestyle and multidisciplinary pharmacotherapeutic options, whereas the option of surgery is useless without managing the comorbidities of the MAFLD. Nanotechnology is an emerging approach addressing MAFLD, where nanoformulations are suggested to improve the safety and physicochemical properties of conventional drugs/herbal medicines, physical, chemical, and physiological stability, and liver-targeting properties. A wide variety of liver nanosystems were constructed and delivered to the liver, only those that addressed the MAFLD were discussed in this review in terms of the nanocarrier classes, particle size, shape, zeta potential and offered dissolution rate(s), the suitable preparation method(s), excipients (with synergistic effects), and the suitable drug/compound for loading. The advantages and challenges of each nanocarrier and the focus on potential promising perspectives in the production of MAFLD nanomedicine were also highlighted.

From Nonalcoholic Fatty Liver Disease (NAFLD) to Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD)-New Terminology in Pediatric Patients as a Step in Good Scientific Direction?

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, which predispose to more serious hepatic conditions. It ranges from simple liver steatosis to nonalcoholic steatohepatitis (NASH), which may progress to cirrhosis, and even end-stage liver disease. Since obesity became one of the most important health concerns wordwide, a considerable increase in the prevalance of NAFLD and other metabolic implications has been observed, both in adults and children. Due to the coexistence of visceral obesity, insulin resistance, dyslipidemia, NAFLD is considered to be the hepatic manifestation of metabolic syndrome (MetS). These relationships between NAFLD and MetS led to the set up in adults of a new term combining both of these conditions, called metabolic dysfunction-associated fatty liver disease (MAFLD). Based on these findings, we propose a set of criteria, which may be useful to diagnose MAFLD in children and adolescents.

Prevalence of elevated liver enzymes and comorbidities in children and adolescents with overweight and obesity

AIM

We investigated the prevalence of elevated liver aminotransferases (ALT) and additional comorbidities in a large cohort of Israeli children and adolescents with overweight and obesity.

METHODS

This study included data from medical records of 2- to 18-year-old children and adolescents, with body mass index (BMI) in the overweight or obesity range (WHO definitions), for whom ALT testing was performed.

RESULTS

Overweight was present in 50 418 (10.7%) and obesity in 70 515 (15.0%). Elevated ALT, above 30 IU/L (0.51 μkat/L), was reported in 2245 (7.2%) of children with overweight and 5475 (16.8%) of children with obesity (P < .0001). Compared to children with overweight and obesity and ALT within normal range, children with elevated ALT were older (11.9 ± 4.2 vs 10.9 ± 4.2, P < .001), mostly male (68.0% vs 49.4%, P < .001) and had higher BMI (27.3 ± 6.1vs 24.0 ± 4.8, P < .001). They also had a more unfavourable cardiometabolic profile with significantly higher either systolic or diastolic blood pressure, total cholesterol and triglycerides, and had more than three criteria defining metabolic syndrome.

CONCLUSION

In this large cohort, abnormally elevated ALT was present in a high number of individuals with overweight or obesity. The children and adolescents with abnormal ALT had higher BMI, were older, male and had more cardiometabolic risk factors.

Accuracy of controlled attenuation parameter compared with ultrasound for detecting hepatic steatosis in children with severe obesity

OBJECTIVES

To determine the diagnostic accuracy of controlled attenuation parameter (CAP) on FibroScan® in detecting and grading steatosis in a screening setting and perform a head-to-head comparison with conventional B-mode ultrasound.

METHODS

Sixty children with severe obesity (median BMI z-score 3.37; median age 13.7 years) were evaluated. All underwent CAP and US using a standardized scoring system. Magnetic resonance spectroscopy proton density fat fraction (MRS-PDFF) was used as a reference standard.

RESULTS

Steatosis was present in 36/60 (60%) children. The areas under the ROC (AUROC) of CAP for the detection of grade ≥ S1, ≥ S2, and ≥ S3 steatosis were 0.80 (95% CI: 0.67-0.89), 0.77 (95% CI: 0.65-0.87), and 0.79 (95% CI: 0.66-0.88), respectively. The AUROC of US for the detection of grade ≥ S1 steatosis was 0.68 (95% CI: 0.55-0.80) and not significantly different from that of CAP (p = 0.09). For detecting ≥ S1 steatosis, using the optimal cutoffs, CAP (277 dB/m) and US (US steatosis score ≥ 2) had a sensitivity of 75% and 61% and a specificity of 75% and 71%, respectively. When using echogenicity of liver parenchyma as only the scoring item, US had a sensitivity of 70% and specificity of 46% to detect ≥ S1 steatosis. The difference in specificity of CAP and US when using only echogenicity of liver parenchyma of 29% was significant (p = 0.04).

CONCLUSION

The overall performance of CAP is not significantly better than that of US in detecting steatosis in children with obesity, provided that the standardized scoring of US features is applied. When US is based on liver echogenicity only, CAP outperforms US in screening for any steatosis (≥ S1).

KEY POINTS

• The areas under the ROC curves of CAP and ultrasound (US) for detecting grade ≥ S1 steatosis were 0.80 and 0.68, respectively, and were not significantly different (p = 0.09). • For detecting grade ≥ S1 steatosis in severely obese children, CAP had a sensitivity of 75% and a specificity of 75% at its optimal cutoff value of 277 dB/m. • For detecting grade ≥ S1 steatosis in clinical practice, both CAP and US can be used, provided that the standardized scoring of US images is used.

Readiness to Change and Prospective Effects of Weight Management Programs in Pediatric Nonalcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is an increasing problem in pediatrics with limited treatment options. We prospectively assessed outcomes in patients managed in a hepatology clinic (HC) alone vs. those managed in combination with a multidisciplinary weight management program (MWMP). We describe each group's readiness to change at the time of NAFLD diagnosis. Patients diagnosed with NAFLD were given a modified Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES) at enrollment (T1) to assess readiness to change. They were then followed at 3-9 months (T2) and at 10-15 months (T3). Linear mixed models were used to evaluate changes in body mass index (BMI), BMI z-score, and transaminases over time and between the two groups. There were no significant treatment group main effects or treatment × time interactions for our primary end points for HC alone (n = 75) or with MWMP (n = 18). There was a significant main effect for time for BMI z-score, with BMI z-scores declining on average by 0.0568 (P = 0.004) from visit to visit. Low SOCRATES subscales scores in HC alone (n = 33) or with MWMP (n = 4) suggested a patient population with low recognition of disease and likelihood of taking steps for change. Patients with obesity and NAFLD had low scores on all three SOCRATES subscales. Despite this, both groups had improvement in BMI z-score without significant difference between the two treatment groups in other primary end points. Further study is needed to identify the most effective patient selection and treatment strategies for pediatric patients with NAFLD, including pharmacotherapy and surgery.

Childhood Obesity and Respiratory Diseases: Which Link?

Prevalence of childhood obesity is progressively increasing, reaching worldwide levels of 5.6% in girls and of 7.8% in boys. Several evidences showed that obesity is a major preventable risk factor and disease modifier of some respiratory conditions such as asthma and Obstructive Sleep Apnea Syndrome (OSAS). Co-occurrence of asthma and obesity may be due to common pathogenetic factors including exposure to air pollutants and tobacco smoking, Western diet, and low Vitamin D levels. Lung growth and dysanapsis phenomenon in asthmatic obese children play a role in impaired respiratory function which appears to be different than in adults. Genes involved in both asthma and obesity have been identified, though a gene-by-environment interaction has not been properly investigated yet. The identification of modifiable environmental factors influencing gene expression through epigenetic mechanisms may change the natural history of both diseases. Another important pediatric respiratory condition associated with obesity is Sleep-Disordered Breathing (SDB), especially Obstructive Sleep Apnea Syndrome (OSAS). OSAS and obesity are linked by a bidirectional causality, where the effects of one affect the other. The factors most involved in the association between OSAS and obesity are oxidative stress, systemic inflammation, and gut microbiota. In OSAS pathogenesis, obesity's role appears to be mainly due to mechanical factors leading to an increase of respiratory work at night-time. However, a causal link between obesity-related inflammatory state and OSAS pathogenesis still needs to be properly confirmed. To prevent obesity and its complications, family education and precocious lifestyle changes are critical. A healthy diet may lead to an improved quality of life in obese children suffering from respiratory diseases. The present review aimed to investigate the links between obesity, asthma and OSAS, focusing on the available evidence and looking for future research fields.

Advances in the Epidemiology, Diagnosis, and Management of Pediatric Fatty Liver Disease

PURPOSE

Nonalcoholic fatty liver (NAFL) is a major contributor to pediatric liver disease. This review evaluated the current literature on prevalence, screening, diagnosis, and management of NAFL in children and explored recent advances in the field of pediatric NAFL.

METHODS

A PubMed search was performed for manuscripts describing disease burden, diagnosis, and management strategies in pediatric NAFL published within the past 15 years. Systematic reviews, clinical practice guidelines, randomized controlled trials, and cohort and case-control studies were reviewed for the purpose of this article.

FINDINGS

The prevalence of NAFL in children is increasing. It is a leading cause of liver-related morbidity and mortality in children. Screening and diagnosis of NAFL in children are a challenge. Lifestyle changes and exercise are the cornerstones of the management of NAFL.

IMPLICATIONS

Further research is needed to develop better screening and diagnostic tools for pediatric NAFL, including noninvasive diagnostics. NAFL therapeutics is another area of much-needed, ongoing research.

Evaluating the Efficacy of Carum Copticum Seeds on the Treatment of Patients with Nonalcoholic Fatty Liver Disease: A Multi-Center, Randomized, Triple–Blind, Placebo-Controlled Clinical Trial Study

Background: The increased prevalence of Nonalcoholic Fatty Liver Disease (NAFLD) has caused several concerns. Besides, there are concerns about the side effects of the drugs used to treat this condition. Since the current treatments are not effective in treating NAFLD, developing a novel therapeutic option based on some medicinal plants is necessary. Few studies have investigated the natural drugs and their effects (e.g., extracts of Carum Copticum Seeds (CCS)) on these patients. Objectives: The current study intended to evaluate the safety and efficacy of CCS extracts on liver enzymes, serum lipids, as well as the grade of fatty liver, and anthropometric measurements in patients with nonalcoholic fatty liver disease. Methods: In this multi-center, randomized, triple-blind, placebo-controlled clinical trial study, 90 patients with grades of 1 to 3 of nonalcoholic fatty liver disease referred to two medical centers located in Tehran (Iran) in 2019 are examined. Diet and exercise were recommended for patients three times a day in eight weeks, in addition to taking 500 mg capsules (aqueous extracts of Ajwain seeds and placebo for treatment and placebo groups). Results: Medical records of 68 patients were reviewed, 48 (71%) male and 20 (29%) female. Both groups were similar concerning demographic and baseline characteristics. The total score of the Leeds questionnaire [-14.03 vs. -7.49, P = 0.048], Triglyceride (TG) [-4.45 vs. 10.03, P = 0.017], and Alanine Aminotransferase (ALT) [-14.71 vs. -4.79, P = 0.012] were significantly changed in the treatment group compared to the control group. Nevertheless, a different situation was observed for Aspartate Aminotransferase (AST) [-7.08 vs. -4.84, P = 0.314], Fasting Blood Sugar (FBS) [-2.88 vs. -2.81, P = 0.207], and Body Mass Index (BMI) [-0.59 vs. -0.39, P = 0.095]. Although a significant change was found in both groups, the amount of decline was similar for both groups. In both groups, the cholesterol, High-Density Lipoprotein (HDL), and Low-Density Lipoprotein (LDL) did not change significantly. The sonographic findings indicated significantly higher improvements in the intervention group than the placebo group (RR = 2.43, 95% CI (1.15-5.65), and P value = 0.034). Conclusions: The result of this study supports the efficacy of Carum copticum seeds in the treatment of nonalcoholic fatty liver disease patients. It was found that CCS with a significant reduction in ALT, TG, and relative reduction of BMI can help physicians to manage other metabolic disorders associated with NAFLD, such as obesity and hyperlipidemia.

Real-time monitoring of liver fibrosis through embedded sensors in a microphysiological system

Hepatic fibrosis is a foreshadowing of future adverse events like liver cirrhosis, liver failure, and cancer. Hepatic stellate cell activation is the main event of liver fibrosis, which results in excessive extracellular matrix deposition and hepatic parenchyma's disintegration. Several biochemical and molecular assays have been introduced for in vitro study of the hepatic fibrosis progression. However, they do not forecast real-time events happening to the in vitro models. Trans-epithelial electrical resistance (TEER) is used in cell culture science to measure cell monolayer barrier integrity. Herein, we explored TEER measurement's utility for monitoring fibrosis development in a dynamic cell culture microphysiological system. Immortal HepG2 cells and fibroblasts were co-cultured, and transforming growth factor β1 (TGF-β1) was used as a fibrosis stimulus to create a liver fibrosis-on-chip model. A glass chip-based embedded TEER and reactive oxygen species (ROS) sensors were employed to gauge the effect of TGF-β1 within the microphysiological system, which promotes a positive feedback response in fibrosis development. Furthermore, albumin, Urea, CYP450 measurements, and immunofluorescent microscopy were performed to correlate the following data with embedded sensors responses. We found that chip embedded electrochemical sensors could be used as a potential substitute for conventional end-point assays for studying fibrosis in microphysiological systems.

Non-alcoholic fatty liver disease: a metabolic burden promoting atherosclerosis

Non-alcoholic fatty liver disease (NAFLD) has become the fastest growing chronic liver disease, with a prevalence of up to 25% worldwide. Individuals with NAFLD have a high risk of disease progression to cirrhosis, hepatocellular carcinoma (HCC), and liver failure. With the exception of intrahepatic burden, cardiovascular disease (CVD) and especially atherosclerosis (AS) are common complications of NAFLD. Furthermore, CVD is a major cause of death in NAFLD patients. Additionally, AS is a metabolic disorder highly associated with NAFLD, and individual NAFLD pathologies can greatly increase the risk of AS. It is increasingly clear that AS-associated endothelial cell damage, inflammatory cell activation, and smooth muscle cell proliferation are extensively impacted by NAFLD-induced systematic dyslipidemia, inflammation, oxidative stress, the production of hepatokines, and coagulations. In clinical trials, drug candidates for NAFLD management have displayed promising effects for the treatment of AS. In this review, we summarize the key molecular events and cellular factors contributing to the metabolic burden induced by NAFLD on AS, and discuss therapeutic strategies for the improvement of AS in individuals with NAFLD.

Hepatic Presentation of Late-Onset Multiple Acyl-CoA Dehydrogenase Deficiency (MADD): Case Report and Systematic Review

Diagnosis of pediatric steatohepatitis is a challenging issue due to a vast number of established and novel causes. Here, we report a child with Multiple Acyl-CoA Dehydrogenase Deficiency (MADD) presenting with an underrated muscle weakness, exercise intolerance and an atypically severe steatotic liver involvement. A systematic literature review of liver involvement in MADD was performed as well. Our patient is a 11-year-old otherwise healthy, non-obese, male child admitted for some weakness/asthenia, vomiting and recurrent severe hypertransaminasemia (aspartate and alanine aminotransferases up to ×20 times upper limit of normal). Hepatic ultrasound showed a bright liver. MRI detected mild lipid storage of thighs muscles. A liver biopsy showed a micro-macrovacuolar steatohepatitis with minimal fibrosis. Main causes of hypertransaminasemia were ruled out. Serum aminoacids (increased proline), acylcarnitines (increased C4-C18) and a large excretion of urinary glutaric acid, ethylmalonic, butyric, isobutyric, 2-methyl-butyric and isovaleric acids suggested a diagnosis of MADD. Serum acylcarnitines and urinary organic acids fluctuated overtime paralleling serum transaminases during periods of illness/catabolic stress, confirming their recurrent nature. Genetic testing confirmed the diagnosis [homozygous c.1658A > G (p.Tyr553Cys) in exon 12 of the ETFDH gene]. Lipid-restricted diet and riboflavin treatment rapidly ameliorated symptoms, hepatic ultrasonography/enzymes, and metabolic profiles. Literature review (37 retrieved eligible studies, 283 patients) showed that liver is an extramuscular organ rarely involved in late-onset MADD (70 patients), and that amongst 45 patients who had fatty liver only nine had severe presentation. Conclusion: MADD is a disorder with a clinically heterogeneous phenotype. Our study suggests that MADD warrants consideration in the work-up of obesity-unrelated severe steatohepatitis.

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.

Non-alcoholic fatty liver disease and childhood obesity

Non-alcoholic fatty liver disease (NAFLD) in children and adolescents has an estimated prevalence of 36.1% in the context of obesity. This figure is anticipated to increase in conjunction with the global obesity epidemic. Worryingly, NAFLD in childhood persisting into adulthood is likely to be harmful, contributing to significant hepatic and extrahepatic morbidities. Early disease detection is required, although the optimum timing, frequency and mode of screening remains undetermined. While the efficacy of several medications, antioxidants, fatty acid supplements and probiotics has been investigated in children, healthy eating and physical activity remain the only prevention and treatment strategies for paediatric NAFLD. This short review discusses the epidemiology, diagnosis, pathogenesis and management of NAFLD in childhood obesity.

Metabolically healthy overweight adolescents: definition and components

PURPOSE

In adolescents, the definition and clinical implications of metabolically healthy overweight (MHO) status have not been established. This study aimed to investigate the prevalence of MHO according to its most widespread definition, which is based on metabolic syndrome (MS), and to explore further metabolic indicators such as Homeostatic Model Assessment of Insulin Resistance, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, and C-reactive protein levels, together with metabolic health predictors in a sample of adolescents attending a pediatric obesity clinic.

METHODS

Data from 487 adolescents categorized as overweight (52.6% females, 88.1% white), with a mean body mass index (BMI) z-score of 2.74 (±1.07 standard deviation [SD]), and a mean age of 14.4 years (±2.2 SD) were cross-sectionally analyzed. From this original sample, a subsample of 176 adolescents underwent a second assessment at 12 (±6 SD) months for longitudinal analysis.

RESULTS

From the 487 adolescents originally analyzed, 200 (41.1%) were categorized as MHO, but only 93 (19.1%) had none of the metabolic indicators considered in this study. According to longitudinal analysis, 30 of the 68 adolescents (44%) categorized as MHO at baseline became non-MHO over time. BMI z-score was the best predictor of metabolic health both in cross-sectional and longitudinal analyses. Increased BMI z-score reduced the odds of being categorized as MHO (odds ratio [OR], 0.6; 95% confidence interval [CI], 0.4-0.9; P=.008) and increased the odds of having hypertension (OR 2.1, 95% CI: 1.4-3.3, P=0.001), insulin resistance (OR, 2.4; 95% CI, 1.4-4.1, P=0.001), or a proinflammatory state (OR, 1.2; 95% CI, 1.1-1.3, P=0.002).

CONCLUSION

Diagnosis of MHO should not be exclusively based on MS parameters, and other metabolic indicators should be considered. Adolescents categorized as overweight should participate in weight-management lifestyle interventions regardless of their metabolic health phenotype.

APOC3 rs2070667 Associates with Serum Triglyceride Profile and Hepatic Inflammation in Nonalcoholic Fatty Liver Disease

Single-nucleotide polymorphisms (SNPs) of apolipoprotein C3 (APOC3) play important role in lipid metabolism, and dyslipidemia underlies nonalcoholic fatty liver disease (NAFLD). But the correlation of serum lipidomics, APOC3 SNPs, and NAFLD remains limited understood. Enrolling thirty-four biopsy-proven NAFLD patients from Tianjin, Shanghai, Fujian, we investigated their APOC3 genotype and serum lipid profile by DNA sequencing and ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), respectively. Scoring of hepatocyte steatosis, ballooning, lobular inflammation, and liver fibrosis was then performed to reveal the role of lipidomics-affecting APOC3 SNPs in NAFLD-specific pathological alterations. Here, we reported that APOC3 SNPs (rs4225, rs4520, rs5128, rs2070666, and rs2070667) intimately correlated to serum lipidomics in NAFLD patients. A allele instead of G allele at rs2070667, which dominated the SNPs underlying lipidomic alteration, exhibited downregulatory effect on triacylglycerols (TGs: TG 54 : 7, TG 54 : 8, and TG 56 : 9) containing polyunsaturated fatty acid (PUFA). Moreover, subjects with low-level PUFA-containing TGs were predisposed to high-grade lobular inflammation (TG 54 : 7, rho = -0.454 and P = 0.007; TG 54 : 8, rho = -0.411 and P =0.016; TG 56 : 9, rho = -0.481 and P = 0.004). The significant correlation of APOC3 rs2070667 and inflammation grading [G/G vs. G/A+A/A: 0.00 (0.00 and 1.00) vs. 1.50 (0.75 and 2.00), P = 0.022] further confirmed its pathological action on the basis of lipidomics-impacting activity. These findings suggest an inhibitory effect of A allele at APOC3 rs2070667 on serum levels of PUFA-containing TGs, which are associated with high-grade lobular inflammation in NAFLD patients.

Nonalcoholic Fatty Liver Disease and Estimated Insulin Resistance in Obese Youth: A Mendelian Randomization Analysis

CONTEXT

Nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR) and predicts type 2 diabetes. Currently, it is uncertain whether NAFLD may directly cause IR or vice versa.

OBJECTIVE

To test the hypothesis that NAFLD is causally related to IR.

DESIGN AND METHODS

We performed a Mendelian randomization (MR) in 904 obese children/adolescents using an NAFLD-related genetic risk score (GRS) as an instrumental variable. We assessed NAFLD by ultrasonography and IR by homeostasis model assessment (HOMA-IR). We also interrogated the MAGIC Consortium dataset of 46 186 adults to assess the association between PNPLA3 rs738409 (ie, the most robust NAFLD-related polymorphism) and HOMA-IR, and we performed a 2-sample MR with 2 large datasets to test reverse causation (HOMA-IR increasing the risk of NAFLD).

RESULTS

Nonalcoholic fatty liver disease prevalence increased by 20% for every increase in the GRS (β-coefficient = 0.20, P < 0.001), and NAFLD was associated with ln-HOMA-IR (β-coefficient = 0.28, P < 0.001). Thus, the expected increase in ln-HOMA-IR for every increase in the GRS (expected β-coefficient) was 0.056 (0.28*0.20) in the case of complete NAFLD-HOMA-IR causal association, and 0.042 in the case of 75% causality. In our cohort, the GRS did not predict ln-HOMA-IR (β-coefficient = 0.007, P = 0.75). In the MAGIC cohort, the PNPLA3 rs738409 did not associate with ln-HOMA-IR. The 2-sample MR failed to show a causal association between ln-HOMA-IR and NAFLD.

CONCLUSIONS

Our study shows that genetically-influenced NAFLD does not increase HOMA-IR, and genetically-influenced HOMA-IR does not increase the risk of NAFLD. Shared pathogenic pathways or NAFLD subtypes not "captured" by our MR design might underpin the association between NAFLD and HOMA-IR.

Noninvasive diagnostic tools for pediatric NAFLD: where are we now?

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of liver disease in the pediatric population. It is a significant liver complication of obesity that also prominently affects children. Over the past decade, several noninvasive methods have been investigated for replacing liver biopsy to identify which children with NAFLD have nonalcoholic steatohepatitis (NASH) and fibrosis. These methods that aim to differentiate the type and extent of liver damage are based on two main different methodologies: a 'biological' approach centered on the quantification of circulating biomarkers; and a 'physical' approach established by analyzing different imaging data.

AREAS COVERED

In this review, we illustrate the state of the art and recent discoveries on noninvasive methods for the diagnosis of NAFLD, NASH, and advanced fibrosis.

EXPERT OPINION

Currently, noninvasive tests cannot diagnose NASH or determine the degree of fibrosis. However, several lines of evidence have suggested that if these tests are used in a complementary way with other laboratory tests and imaging they have the potential to be used to monitor progression of disease and response to therapy in pediatric NAFLD. Future scientific research will focus on combining these methods with multiple potential predictors of genetic susceptibility.

Lipidomics in Nonalcoholic Fatty Liver Disease: Exploring Serum Lipids as Biomarkers for Pediatric Nonalcoholic Fatty Liver Disease

OBJECTIVES

Disturbances in lipid metabolism play an important role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Using lipidomics, an analytical technique that is used to broadly survey lipid metabolism, we searched for biomarkers in plasma that are correlated with the presence of hepatic steatosis in children with obesity.

METHODS

Lipidomics was performed in plasma samples of 21 children with obesity in whom steatosis was detected using proton magnetic resonance spectroscopy (H-MRS) and were compared with the lipidome of 21 samples of nonsteatotic subjects with obesity.

RESULTS

Forty-two samples were analyzed (57% boys; median age 15 years). A total of 18 lipid classes constituting 839 different lipid species were identified. A statistically significant increase in alkyldiacylglycerol (TG[O]) and phosphatidylethanolamine (PE) species and a significant decrease in alkyl/alkenyl-phosphatidylethanolamine (PE[O]), alkyl/alkenyl-lysophosphatidylethanolamine (LPE[O]) and alkyl/alkenyl-phosphatidylcholine (PC[O]) was observed in children with hepatic steatosis compared with controls. Twelve individual lipid species of 3 lipid classes were significantly increased in steatotic subjects compared with controls.

CONCLUSIONS

In this pilot study, we found statistically significant alterations in 5 major lipid classes and 12 individual lipid species in children with steatosis. These might be potential biomarkers for pediatric NAFLD. Lipidomic studies in larger cohorts of children are needed to determine the diagnostic value of these lipids and determine whether results can be generalized for different age groups and ethnic backgrounds.

Update on Preventive Cardiology

Although progress had been made in reducing cardiovascular disease (CVD) mortality, the positive trend has reversed in recent years, and CVD remains the most common cause of mortality in US women and men. Youth represent the future of CVD prevention; emerging evidence suggests exposure to risk factors in children contributes to atherosclerosis and results in vascular changes and increased CVD events. The contributors to CVD include those commonly seen in adults. This article reviews hypercholesterolemia, hypertension, obesity, diabetes, and smoking. It discusses the prevalence of each disease, diagnosis, treatment, and cardiovascular complications.

Estimation of the risk of fibrosis in children with nonalcoholic fatty liver disease

Aim of the study

Assessment of liver fibrosis as a predictive factor of liver-related mortality in children with nonalcoholic fatty liver disease (NAFLD) is crucial. This study aims to estimate the risk of fibrosis using noninvasive markers.

Material and methods

The study group of 49 children with NAFLD (age range 3-16, mean 10.51 ±3.18 years) was created. The diagnosis was based on clinical picture, abdominal ultrasound, and laboratory tests; four children underwent liver biopsy. Then homeostatic model assessment (HOMA-IR) and noninvasive hepatic fibrosis scores were calculated, and patients were divided into four groups depending on body mass index (BMI, obese vs. lean) and aminotransferases.

Results

71.43% of patients were obese, and 14.29% were overweight. We found that overweight children had lower mean corpuscular volume (MCV) than lean patients. In a group of patients with a high risk of fibrosis or significant fibrosis due to pediatric NAFLD fibrosis score (PNFS), higher alanine aminotransferase (ALT) to platelet ratio (APRI) values were observed. The highest values of APRI were found in a group of lean patients with elevated aminotransferases and the highest value of PNFS – among obese patients with elevated aminotransferases. A strong significant correlation between APRI and PNFS was found (r = 0.88).

Conclusions

Apart from aminotransferase activity, complete blood count should be assessed looking for lower MCV caused by iron deficiency. In contrast to FIB-4 (fibrosis score), PNFS and APRI proved to be more accurate in our group. PNFS seems to be appropriate to evaluate fibrosis in a noninvasive diagnostic algorithm.

CYTOKERATIN-18 AS A MARKER OF NON-ALCOHOLIC FATTY LIVER DISEASE IN OBESE ADOLESCENTS

In parallel with the obesity epidemic in the world, the prevalence of non-alcoholic fatty liver disease among children and adolescents is growing. Current data suggest that insulin resistance is one of the main factors in the pathogenesis of non-alcoholic fatty liver disease, and the content of fragments of caspase-cleaved cytokeratin-18 in the blood serum may be one of the informative indicators of non-alcoholic fatty liver disease progression. The aim. To determine mechanisms of formation and progression of non-alcoholic fatty liver disease in obese children and adolescents by evaluating the level of cytokeratin-18. Materials and methods. The study involved 46 adolescents with obesity and non-alcoholic fatty liver disease aged 12–17 years: 19 boys (41.3 %) and 27 girls (58.7 %). Clinical (weight, height, waist and hip circumference), laboratory (glucose, immunoreactive insulin, lipid metabolism, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transpeptidase, cytokeratin-18) parameters were studied and instrumental examination (abdominal ultrasound) was performed. To assess insulin resistance the triglyceride-glucose index was calculated. Results. Depending on the presence of insulin resistance patients were divided into two groups: 21 (45.7 %) of adolescents with insulin resistance and 25 (54.3 %) of adolescents without insulin resistance. Blood tests in patients with insulin resistance revealed significantly higher levels of total cholesterol, triglycerides, very low-density lipoprotein cholesterol, fasting immunoreactive insulin, cytokeratin-18 and gamma-glutamyl transpeptidase. All adolescents were divided into 2 groups depending on the level of cytokeratin-18: patients with cytokeratin-18 >233 mIU/ml and <233 mIU/ml (15 (32.6 %) and 31 (67.4 %) respectively). It was found that there were significantly more patients with insulin resistance in the group with the level of cytokeratin-18 >233 mIU/ml. Conclusion. In obese adolescents with non-alcoholic fatty liver disease insulin resistance is associated with more pronounced disorders of lipid and carbohydrate metabolism and higher levels of markers that characterize the state of the liver such as cytokeratin-18 and gamma-glutamyl transpeptidase. Adolescents with obesity and non-alcoholic fatty liver disease with a threshold level of cytokeratin-18, which indicates the transformation of steatosis into steatohepatitis, two times more often have present insulin resistance.

PNPLA3 gene polymorphism is associated with liver steatosis in children with Down syndrome

BACKGROUND AND AIMS

We previously demonstrated that children with Down syndrome (DS) exhibited a greater risk of steatosis than the general pediatric population. This trend was independent of obese phenotype, thus suggesting a role of genetic predisposition. Therefore, we investigated the prevalence of non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS) in function of genetic susceptibility and adipocytokine levels in children with DS.

METHODS AND RESULTS

A total of 84 Caucasian children with DS (age range 5-17 years), were included in this study. For all children, we collected data on anthropometric and biochemical parameters, and liver ultrasound (US). We also measured adipocytokines circulating levels and specific polymorphisms closed to NAFLD. We found a prevalence of 64.3% of liver steatosis at US, with a severe steatosis of about 4% in children with DS. The presence of steatosis in children with DS was associated with the presence of patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 variant, which also correlated with interleukin (IL)-6 levels. Moreover, we found that the 52.4% had a waist circumference > 90th percentile, 21.4% were hypertensive, 7.14% had hyperglycemia, 9.5% had hypertriglyceridemia, and 17.9% showed high-density lipoprotein cholesterol ≤ 40 mg/dl. Finally, the IL-6 and adiponectin levels correlated with steatosis, and several adipocytokines correlated with single MetS traits in children with DS.

CONCLUSION

The present study explores for the first time potential pathomechanisms connecting pediatric NAFLD and MetS in DS. We found that the PNPLA3 variant is associated with steatosis, but not with MetS, in children with DS.

Endocan and Lumican in Relation to Cardiometabolic Risk in a Pediatric Overweight and Obese Cohort: A Cross-Sectional Study

The aim of the study was to evaluate serum Endocan and Lumican levels as biomarkers for pediatric Nonalcoholic Fatty Liver Disease (NAFLD) and to explore their associations with pediatric cardiometabolic risk factors. We conducted a cross-sectional study on 68 pediatric obese and overweight (O&O) patients. Ten healthy controls were recruited. Serum Lumican and Endocan levels were analyzed using ELISA kits. O&O patients had lower levels of Endocan compared to healthy controls (p < 0.001). There were no differences between serum Endocan levels in O&O patients with NAFLD and those without (p = 0.53). Patients considered having Nonalcoholic Steatohepatitis (NASH) had lower Endocan levels compared to O&O patients without NASH (p = 0.026). Patients with metabolic syndrome had lower levels of Endocan (p = 0.003). There were no significant differences between serum Lumican levels in O&O children compared to healthy controls. Lumican levels were higher in patients with hypertension (p = 0.04). In O&O patients, Lumican levels were negatively correlated with Endocan levels (r = −0.37, p = 0.002). Endocan seems a promising biomarker for the evaluation of pediatric NASH. Lumican was not confirmed as a biomarker for NAFLD in our cohort but was associated with higher arterial pressure. Low Endocan levels are accompanied by high serum Lumican levels, and this could be an early signature of cardiometabolic risk.

Updates in non-alcoholic fatty liver disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in childhood. There is an increase in disease prevalence and diagnoses as it is difficult to diagnose the problem. There are currently no effective medications. Management of NAFLD is a challenge for primary care clinicians and subspecialists. This paper provides guidelines for disease screening, diagnosis, management, and algorithm for subspecialty referral.

Transmembrane 6 superfamily member 2 167K allele improves renal function in children with obesity

BACKGROUND

The transmembrane 6 superfamily member 2 (TM6SF2) E167K polymorphism influences estimated glomerular filtration rate (eGFR) in adults without diabetes and without obesity. We aimed exploring the impact of this polymorphism on eGFR in children with obesity with and without non-alcoholic fatty liver disease (NAFLD).

METHODS

We genotyped 531 children with obesity for TM6SF2 E167K polymorphism. NAFLD was defined by ultrasound detected liver steatosis and/or ALT > 40 IU/L.

RESULTS

Patients carrying the TM6SF2 167K allele showed higher eGFR levels compared with E167 homozygous patients both among subjects with and without NAFLD. A general linear model confirmed a direct and significant association of eGFR values with TM6SF2 genotype both in patients with and without NAFLD. This association, however, was stronger in patients with NAFLD.

CONCLUSIONS

Children with obesity carrying the TM6SF2 167K allele show higher eGFR levels compared with E167 allele homozygous subjects, independently of NAFLD. A major effect of this polymorphism in the presence of NAFLD was captured.

Serum visfatin level as a noninvasive marker for nonalcoholic fatty liver disease in children and adolescents with obesity: relation to transient elastography with controlled attenuation parameter

BACKGROUND

Obesity is associated with an increased risk of nonalcoholic fatty liver disease (NAFLD). Visfatin is an adipokine produced by visceral fat tissue and liver cells. Transient elastography with controlled attenuation parameter (CAP) noninvasively assesses liver fibrosis and steatosis.

AIM

To measure visfatin level in 80 children and adolescents with obesity as a potential biomarker for NAFLD and assess its relation to transient elastography.

METHODS

Abdominal ultrasound, liver stiffness and CAP measurements were performed for all patients. Fasting lipid profile, fasting blood glucose, insulin level, liver and kidney functions, coagulation profile and serum visfatin levels were assessed.

RESULTS

Among patients with obesity, 31 (38.8%) had NAFLD and 16 (20%) patients had elevated alanine aminotransferase (ALT), while 9 (11.2%) had both NAFLD and elevated ALT. Transient elastography showed that 12.5% had fibrosis stage F1, 2.5% had F2 and another 2.5% had F3 while none had F4. Using CAP, 23.8, 13.8 and 17.5% had S1, S2 and S3, respectively. Serum visfatin levels were significantly elevated in all patients compared with nonobese controls. Higher visfatin levels were found among patients with dyslipidemia, NAFLD, elevated ALT and steatosis defined by CAP. Serum visfatin was related to the degree of fibrosis and steatosis. Visfatin cutoff value 18 ng/mL could significantly detect the presence of NAFLD with 83.9% sensitivity and 81.4% specificity. Serum visfatin was positively correlated to BMI, waist circumference, waist/hip ratio, ALT, total cholesterol, liver stiffness and CAP.

CONCLUSIONS

Visfatin could be a promising serum biomarker for monitoring liver disease among pediatric patients with obesity.

Effects of a carbohydrate-restricted diet on hepatic lipid content in adolescents with non-alcoholic fatty liver disease: A pilot, randomized trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has emerged as the most common form of liver disease among adolescents in industrialized countries. While lifestyle intervention remains the hallmark treatment for NAFLD, the most effective dietary strategy to reverse NAFLD in children is unknown.

OBJECTIVE

The objective of this study was to determine the effects of a moderately CHO-restricted diet (CRD) vs fat-restricted diet (FRD) in adolescents with NAFLD on reduction in liver fat and insulin resistance.

METHODS

Thirty-two children/adolescents (age 9-17) with obesity and NAFLD were randomized to a CRD (<25:25:>50% energy from CHO:protein:fat) or FRD (55:25:20) for 8 weeks. Caloric intakes were calculated to be weight maintaining. Change in hepatic lipid content was measured via magnetic resonance imaging, body composition via dual energy X ray absorptiometry and insulin resistance via a fasting blood sample.

RESULTS

Change in hepatic lipid did not differ with diet, but declined significantly (-6.0 ± 4.7%, P < .001 only within the CRD group. We found significantly greater decreases in insulin resistance (HOMA-IR, <.05), abdominal fat mass (P < .01) and body fat mass (P < .01) in response to the CRD vs FRD.

CONCLUSION

These findings suggest that consumption of a moderately CHO-restricted diet may result in decreased hepatic lipid as well as improvements in body composition and insulin resistance in adolescents with NAFLD even in the absence of intentional caloric restriction. Larger studies are needed to determine whether a CHO-restricted diet induces change in hepatic lipid independent of change in body fat.

Heightened Plasma Levels of Transforming Growth Factor Beta (TGF-β) and Increased Degree of Systemic Biochemical Perturbation Characterizes Hepatic Steatosis in Overweight Pediatric Patients: A Cross-Sectional Study

Nonalcoholic Fatty Liver Disease (NAFLD) is a common cause of chronic liver disease in childhood and strongly associated with obesity. Routine biochemical non-invasive tests remain with low accuracy for diagnosis of NAFLD. We performed a cross-sectional study to examine potential associations between anthropometric and biochemical parameters, specially TGF-β, a prognosis marker for hepatic steatosis (HS). Between May and October 2019, seventy-two overweight adolescents were enrolled, of which 36 had hepatic steatosis. Hepatic, lipidic and glycemic profiles, and levels of vitamin D, ferritin and TGF-β were analyzed. Hierarchical cluster and a discriminant model using canonical correlations were employed to depict the overall expression profile of biochemical markers and the biochemical degree of perturbation. Median values of alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), and TGF-β were higher in the adolescents with HS. Values of body mass index (BMI)/age and ALT, but not of TGF-β, were gradually increased proportionally to augmentation of steatosis severity. In a multivariate analysis, TGF-β plasma concentrations were associated with occurrence of hepatic steatosis independent of other covariates. Discriminant analysis confirmed that TGF-β concentrations can identify HS cases. Our data reveal that HS patients exhibit a distinct biosignature of biochemical parameters and imply TGF-β as an important biomarker to evaluate risk of steatosis development.

Bone marrow fat change in pediatric patients with non-alcoholic fatty liver disease

Objectives

To investigate changes of fat in bone marrow (BM) and paraspinal muscle (PSM) associated with the degree of fatty liver in pediatric patients with non-alcoholic fatty liver disease (NAFLD) in consideration of age and body mass index (BMI).

Methods

Hepatic fat, BM fat, and PSM fat from proton density fat fraction of liver MRI between June 2015 and April 2019 were quantitatively evaluated on axial images of the fat map at the mid-level of T11-L2 vertebral bodies for BM fat and at the mid-level of L2 for PSM fat. Age, height, and weight at the time of MRI were recorded and BMI was calculated. Correlation analysis was performed.

Results

A total of 147 patients (114 male) were included with a mean age of 13.3 ± 2.9 years (range 7–18 years). The mean fat fractions were 24.3 ± 13.0% (2–53%) in liver, 37.4 ± 8.6% (17.3–56%) in vertebral BM, and 2.7 ± 1.1% (1.0–6.9%) in PSM. Age, height, weight, and BMI were not correlated with liver fat or BM fat. However, weight (ρ = 0.174, p = 0.035) and BMI (ρ = 0.247, p = 0.003) were positively correlated with PSM fat. Liver fat showed positive correlation with BM fat when adjusting age and BMI (ρ = 0.309, p<0.001), but not with PSM fat.

Conclusions

BM fat positively correlates with liver fat, but not with age or BMI in pediatric NAFLD patients.

Associations of physical activity and fitness with hepatic steatosis, liver enzymes, and insulin resistance in children with overweight/obesity

BACKGROUND

Non-alcoholic fatty liver disease is the most common liver disease in childhood and is related to insulin resistance and cardiometabolic risk factors. Evidence supporting the association of fitness and physical activity with hepatic fat, liver enzymes, or triglyceride-to-high-density lipoprotein ratio is scarce in children.

OBJECTIVE

To analyze the associations of physical fitness and physical activity (PA) with percentage hepatic fat, liver enzymes, insulin resistance, and cardiometabolic risk in children with overweight/obesity.

SUBJECTS

A total of 115 children (10.6 ± 1.1 years; 54% girls) with overweight/obesity of the EFIGRO study (ClinicalTrials.gov: NCT02258126) were included in the analyses.

METHODS

Cardiorespiratory fitness (CRF), musculoskeletal fitness and speed-agility were measured by the Alpha-fitness tests, and PA by wGT3X-BT accelerometers. Percentage hepatic fat was assessed by magnetic resonance imaging. Alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST), insulin, glucose, triglycerides (TG), and high-density lipoprotein (HDL) levels were obtained from fasting blood samples. The homeostasis model assessment insulin resistance (HOMA-IR) and AST/ALT and TG/HDL ratios were calculated.

RESULTS

Higher CRF was associated with lower percentage hepatic fat (β = -0.266, P = .01) and GGT (β = -0.315, P < .01), and higher AST/ALT ratio (β = 0.306, P < .01). CRF-fit children have lower GGT levels (15 ± 1 vs 17 ± 1 U/L, CRF-fit vs CRF-unfit children, P = .02), HOMA-IR (2.2 ± 0.1 vs 2.9 ± 0.1, P < .01) and TG/HDL ratio (1.4 ± 0.1 vs 1.9 ± 0.1, P = .01) and higher AST/ALT ratio (1.3 ± 0.0 vs 1.2 ± 0.0, P = .03), than CRF-unfit children.

CONCLUSIONS

These findings emphasize the importance of considering the improvement of CRF as a target of programs for preventing hepatic steatosis, type 2 diabetes and cardiovascular diseases in children with overweight.

Causes of secondary non-alcoholic fatty liver disease in non-obese children below 10 years

This study aimed to detect etiologies and histopathological features of non-alcoholic fatty liver disease (NAFLD) in Egyptian children < 10 years from hepatologist perspectives. Infants and children below 10 years of age with biopsy-proven fatty liver over a 6-year period were included. NAFLD activity score was used to detect the presence of non-alcoholic steatohepatitis (NASH). The study included 66 cases whose age ranged between 5 months and 10 years. Transaminases were elevated in 60% patients. Glycogen storage disease (GSD) was the most common diagnosis (33.3%) followed by hepatitis C virus (HCV) (10.6%) and Chanarin-Dorfman syndrome (CDS) (9.1%). The cause of steatosis could not be identified in 28.8% of cases. There was a higher prevalence of secondary causes of NAFLD in patients < 10 years. Liver histopathological examination revealed preserved lobular architecture in 75.7% with minimal-to-mild fibrosis in 79%. Steatosis was macrovesicular in all specimens (severe steatosis in 39.4%). Four patients had NASH. Higher degree of steatosis was associated with more severe fibrosis (P = 0.01).Conclusion: GSD was the commonest cause of secondary NAFLD in Egyptian children < 10 years followed by HCV and CDS with higher degrees of steatosis in younger patients. The degree of fibrosis was significantly related to the degree of steatosis.What is Known:• Primary non-alcoholic fatty liver disease (NAFLD) is rare in children aged less than 10 years.• Secondary causes of NAFLD should be considered in patients who do not have traditional risk factors.What is New:• Glycogen storage disease, hepatitis C virus, and Chanarin-Dorfman syndrome are the commonest causes of secondary NAFLD in Egyptian children (< 10 years) with higher degrees of steatosis in younger patients.• The degree of liver fibrosis is significantly related to the degree of steatosis.

Nonalcoholic Fatty Liver Disease in Children: Unique Considerations and Challenges

Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence in concert with the global epidemic of obesity and is being diagnosed at increasingly younger ages. The unique histologic features and early presentation of disease in pediatrics suggest that children and adults may differ with regard to etiopathogenesis, with children displaying a greater vulnerability to genetic and environmental factors. Of significant relevance to pediatrics, in utero and perinatal stressors may alter the lifelong health trajectory of a child, increasing the risk of NAFLD and other cardiometabolic diseases. The development and progression of disease in childhood is likely to carry increased risk of long-term morbidity. Novel biomarkers and therapeutic agents are needed to avoid the otherwise inevitable health and societal consequences of this rapidly expanding pediatric population.

Utility of MR proton density fat fraction and its correlation with ultrasonography and biochemical markers in nonalcoholic fatty liver disease in overweight adolescents

Background Clinical or biochemical markers that have good correlation with magnetic resonance proton density fat fraction (MR PDFF) can be used as simple tools for the screening for nonalcoholic fatty liver disease (NAFLD) and in determining the degree of fatty infiltration of the liver. The objective of this study was to determine the degree of relationship between MR PDFF and ultrasonography (USG) grades of fatty liver, and clinical and biochemical parameters of adolescents and to determine the sensitivity and specificity of USG for diagnosis of NAFLD. Methods This prospective study included 34 overweight adolescents (mean age, 12.1 ± 1.5 years; range, 10-15.1 years; 10 girls and 24 boys) who underwent both USG and magnetic resonance imaging (MRI). Correlation analysis was performed between MR fat fraction and USG grades of fatty liver, and clinical and biochemical parameters of fatty liver disease. Results MR fat fraction had a moderate positive correlation with serum alanine transaminase (ALT) and aspartate transaminase (AST) (ρ = 0.634, p < 0.001, ρ = 0.516, p = 0.002, respectively) and had a negligible or weak correlation with body mass index (BMI), BMI standard deviation score (SDS), waist circumference (WC), fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR), serum triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and total cholesterol levels. The sensitivity and specificity of USG in the diagnosis of NAFLD were 81% (95% confidence interval 54%-95%) and 50% (27%-73%), respectively. The MR fat fraction had a moderate positive correlation with ultrasound grades of fatty liver (ρ = 0.487, p = 0.003). Conclusions Serum ALT and AST are potential biochemical markers to assess the degree of hepatic steatosis in NAFLD, which needs validation in further studies. USG can be used as a screening tool for NAFLD, but the diagnosis should be confirmed by estimating the MR fat fraction.

Analysis of the dietary factors associated with suspected pediatric nonalcoholic fatty liver disease and potential liver fibrosis: Korean National Health and Nutrition Examination Survey 2014-2017

Background

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased as the obese pediatric population has increased. NAFLD causes progressive liver injury and the only effective treatment is lifestyle modifications. However, few studies have examined the dietary risk factors for pediatric NAFLD or liver fibrosis. Here, we evaluated the dietary factors associated with suspected NAFLD and potential liver fibrosis in Korean children.

Methods

Data collected from 1674 children and adolescents aged 10–18 years during the 2014–2017 Korean National Health and Nutrition Examination Surveys analyzed. The 24-h recall method measured the food consumed 1 day before the survey. The “suspected NAFLD” group included excessive body mass index (BMI) subjects ≥ 85th percentile) with alanine aminotransferase (ALT) levels exceeding the upper normal limit (24.1 U/L for boys and 17.7 U/L for girls); the “healthy control” group included subjects with a BMI and ALT level below these thresholds. Sodium intake was assessed by the urinary sodium-to-urinary specific gravity unit ratio (U-Na-to-SGU ratio). A pediatric NAFLD index (PNFI) higher than 3 indicated potential liver fibrosis.

Results

The overall prevalence of suspected NAFLD and potential liver fibrosis was 8.2 and 4.5%, respectively. The suspected NAFLD group had a larger proportion of males and subject with a greater height, BMI standard deviation score (BMI-SDS), systolic and diastolic blood pressure SDS, waist circumference, hemoglobin A1c, and levels of total cholesterol, triglycerides, aspartate aminotransferase (AST) and ALT than the control group. The suspected NAFLD group presented significantly higher U-Na-to-SGU ratios and cholesterol intake. The PNFI > 3 subgroup included a significantly larger proportion of males and subjects with higher BMI-SDS, AST and ALT values, and intake of water, carbohydrate, protein, calcium, phosphorus, iron and vitamin B2. After adjusting for confounders, male, BMI-SDS, AST, and protein and carbohydrate intake were independent risk factors for potential liver fibrosis. Niacin intake was an independent protective factor for potential liver fibrosis.

Conclusions

Children with suspected NAFLD had higher urinary sodium level and cholesterol intake than healthy controls. Protein and carbohydrate intake were independent risk factors for potential liver fibrosis; niacin was an independent protective factor.

Gender-related metabolic outcomes of laparoscopic sleeve gastrectomy in 6-month follow-up

Introduction

Laparoscopic sleeve gastrectomy (LSG) is recently a leading method in surgical treatment of morbid obesity. The metabolic outcome of intervention may be a result of many factors such as age, gender, preoperative weight loss and dietary restrictions.

Aim

To evaluate gender-related differences in the results of LSG in 6-month follow-up.

Material and methods

The study included 101 patients who underwent LSG at the University Clinical Hospital of Bialystok. Patients were divided and analyzed in 2 groups: males (n = 48) and females (n = 53). The primary analysis included the influence of gender on postoperative weight loss calculated using the percentage of excess weight loss (%EWL) and excess BMI loss (%EBMIL). For secondary outcomes the levels of glucose, insulin, glycated hemoglobin, aspartate transaminase, alanine transaminase, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides and C-reactive protein were analyzed.

Results

A significant influence of patients’ gender was proved for both %EWL (p = 0.026) and %EBMIL (p = 0.001). Females had significantly higher %EWL in 6-month follow-up than males (p = 0.0034). The analysis also showed significantly higher %EBMIL for women at 3 and 6 months observation (p = 0.022 and p < 0.001 respectively).

Conclusions

Laparoscopic sleeve gastrectomy is an effective method of obesity treatment especially in terms of postoperative weight loss. Females seem to benefit more from the procedure when analyzing the parameters of body mass reduction. However, further research is needed to provide strong evidence of an association between gender and the results of LSG.

The rs72613567: TA Variant in the Hydroxysteroid 17-beta Dehydrogenase 13 Gene Reduces Liver Damage in Obese Children

We first investigated in obese children the protective role of the hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13) rs72613567:TA variant in liver damage. Six hundred eighty-five obese children were genotyped for HSD17B13, patatin-like phospholipase domain containing 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2), and membrane bound O-acyltransferase domain containing 7 (MBOAT7) polymorphisms and underwent anthropometrical, ultrasonographic, and biochemical evaluation. Indirect measurement of liver fibrosis (Pediatric NAFLD Fibrosis Index [PNFI]) was calculated. The population was clustered in 2 genetic risk groups based on the numbers of steatogenic alleles (low: carriers up to 3 risk alleles, high: 4-6 risk alleles). Carriers of the HSD17B13 rare A allele showed lower percentage of hepatic steatosis and both lower serum transaminase and PNFI levels than noncarriers, even after adjustments for confounders. These findings were also confirmed in both risk groups. We demonstrated the protective effect of the rs72613567:TA HSD17B13 variant in reducing liver damage in obese children regardless of genetic predisposition.

Inborn errors of metabolism in the differential diagnosis of fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease across all age groups. Obesity, diabetes, and metabolic syndrome, are the primary causes that are closely linked with the development of NAFLD. However, in young children, rare inborn errors of metabolism are predominant secondary causes of NAFLD. Furthermore, inborn errors of metabolism causing hepatosteatosis are often misdiagnosed as NAFLD in adolescents and adults. Many inborn errors of metabolism are treatable disorders and therefore require special consideration. This review aims to summarize the basic characteristics and diagnostic clues of inborn errors of metabolism associated with fatty liver disease. A suggested clinical and laboratory diagnostic approach is also discussed.

Fasting C-peptide is a significant indicator of nonalcoholic fatty liver disease in obese children

AIMS

Whether fasting C-peptide can be a potential indicator for nonalcoholic fatty liver disease (NAFLD) in obese children is unknown. This study aimed to assess whether fasting C-peptide represented a risk factor for NAFLD.

METHODS

A total of 520 obese children (376 male, 144 female) aged 3.4-17.1 years were divided into two groups, obese with NAFLD and non-NAFLD, according to hepatic ultrasound results. Fasting plasma glucose, fasting C-peptide, hemoglobin A1c, renal function, liver function, blood lipid, fasting insulin and blood routine indices were measured. Insulin resistance by homoeostasis model (HOMA-IR) was calculated.

RESULTS

Compared with the non-NAFLD group, the obese children with NAFLD had higher fasting C-peptide, fasting insulin and HOMA-IR (P < 0.001). Stepwise multiple logistic regression models showed that fasting C-peptide (odds ratio: OR = 2.367) was independent indicator of the presence of NAFLD in obese children as well as white blood cell (OR = 1.113), albumin (OR = 1.124), alanine aminotransferase (OR = 1.030), triglycerides (OR = 1.335), and waist circumference (OR = 1.047). Furthermore, after adjustment for confounding variables, the prevalence of NAFLD in obese children was significantly higher according to increased serum fasting C-peptide levels. The adjusted OR for NAFLD according to fasting C-peptide tertiles were 1.00 (as references), 1.896(1.045-3.436), and 4.169(1.822-9.537).

CONCLUSION

Our data suggested that obese children with high level of fasting C-peptide had an increased risk for developing NAFLD.

New Perspectives on Genetic Prediction for Pediatric Metabolic Associated Fatty Liver Disease

Non-alcoholic or recently re-defined metabolic associated fatty liver disease (MAFLD), a spectrum of progressive hepatic disease, has become a public health issue in obese children and adolescents. MAFLD is a complex metabolic disease strongly associated with obesity and insulin resistance. It is not known why not every obese subject will develop MAFLD. Different ethnic/racial groups display differences in MAFLD prevalence, indicating genetic factor plays a role. In the past two decades, sequence variations in genetic loci, including PNPLA3, TM6SF2, GCKR, MBOAT7, HSD17B13, etc. have been shown to confer susceptibility to MAFLD in children and adults. This review article provides an updated viewpoint of genetic predictors related to pediatric MAFLD. We discuss whether these susceptible genes can be clinically used for risk stratification and personalized care. Understanding human genetics and molecular mechanisms can give important information not only for prediction of risk but also on how to design drugs. In view of current epidemic of MAFLD worldwide, it is necessary to identify which children with MAFLD progress rapidly and need earlier intervention. In the future, a comprehensive analysis of individualized genetic and environmental factors may help assess the risk of children with MAFLD and personalize their treatment.

Plasma N-terminal propeptide of type III procollagen accurately predicts liver fibrosis severity in children with non-alcoholic fatty liver disease

BACKGROUND & AIMS

We examined the diagnostic performance of plasma N-terminal propeptide of type III procollagen (PIIINP) levels, aspartate aminotransferase to platelet ratio index (APRI) and Fibrosis-4 (FIB-4) score for predicting non-alcoholic steatohepatitis (NASH) and liver fibrosis stage in children/adolescents with non-alcoholic fatty liver disease (NAFLD).

METHODS

We enrolled 204 children/adolescents with biopsy-proven NAFLD at the "Bambino Gesù" Children's Hospital. We measured plasma PIIINP levels using a commercially available enzyme-linked immunosorbent assay kit and calculated APRI and FIB-4 scores using standard methods.

RESULTS

Children with NASH had higher plasma PIIINP levels, APRI and FIB-4 scores compared with those without NASH (all P < .001). However, PIIINP levels had much better diagnostic performance and accuracy than APRI and FIB-4 scores for predicting liver fibrosis stage. PIIINP levels correlated with the total NAFLD activity score (NAS) and its constituent components (P < .0001). The risk of either NASH or F ≥ 2 fibrosis progressively increased with increasing PIIINP levels (P < .0001), independent of age, gender, adiposity measures, insulin resistance, NAS score and the patatin-like phospholipase domain-containing protein-3 rs738409 polymorphism. For every 3.6 ng/mL increase in PIIINP levels, the likelihood of having F ≥ 2 fibrosis increased by ~14-fold (adjusted-odds ratio 14.1, 95% CI 5.50-35.8, P < .0001) after adjustment for the aforementioned risk factors. The area under the receiver operating characteristics curve was 0.921 (95% CI 0.87-0.97) for F ≥ 2 fibrosis, and 0.993 (95% CI 0.98-1.0) for F3 fibrosis respectively.

CONCLUSIONS

Unlike APRI and FIB-4 scores, plasma PIIINP levels are a promising, non-invasive biomarker for diagnosing liver fibrosis stage in children/adolescents with biopsy-proven NAFLD.

Lipid accumulation product is a predictor of nonalcoholic fatty liver disease in childhood obesity

Background

Lipid accumulation product (LAP) is associated with the presence and severity of nonalcoholic fatty liver disease (NAFLD) in adults.

Purpose

Here we evaluated the ability of LAP to predict NAFLD in obese children.

Methods

Eighty obese children (38 girls; age 6–18 years) were included. Anthropometric measurements and biochemical values were obtained from the patients’ medical records. LAP was calculated as [waist circumference (WC) (cm) – 58]×triglycerides (mmol/L) in girls; [WC (cm) – 65]×triglycerides (mmol/ L) in boys. The minLAP and adjLAP were described (3% and 50% of WC values, respectively) and the total/high-density lipoprotein cholesterol index (TC/HDL-C) was calculated. NAFLD was observed on ultrasound, and patients were divided into 3 groups by steatosis grade (normal, grade 0; mild, grade 1; moderate-severe, grade 2–3). The area under the curve (AUC) and appropriate index cutoff points were calculated by receiver operator characteristic analysis.

Results

LAP was positively correlated with puberty stage (rho=0.409; P<0.001), fasting insulin (rho= 0.507; P<0.001), homeostasis model assessment of insulin resistance (rho=0.470; P<0.001), uric acid (rho=0.522; P<0.001), and TC/HDL-C (rho=0.494; P<0.001) and negatively correlated with HDL-C (rho=-3.833; P<0.001). LAP values could be used to diagnose hepatosteatosis (AUC=0.698; P=0.002). The LAP, adjLAP, and minLAP cutoff values were 42.7 (P=0.002), 40.05 (P=0.003), and 53.47 (P= 0.08), respectively. For LAP, the differences between the normal and mild groups (P=0.035) and the normal and moderate-severe groups were statistically significant (P=0.037), whereas the difference between the mild and moderate-severe groups was not (P>0.005). There was a statistically significant difference between the normal and mild groups for adjLAP (P=0.043) but not between the other groups (P>0.005). There was no significant intergroup difference in minLAP (P>0.005).

Conclusion

LAP is a powerful and easy tool to predict NAFLD in childhood. If LAP is ≥42.7, NAFLD should be suspected. This is the first study to assess LAP diagnostic accuracy for childhood obesity.