Incidence of SARS-CoV-2 Seropositivity in Pediatric Healthcare Workers Prior to Widespread Vaccination: A Five-month Longitudinal Cohort Study

OBJECTIVES

Determine SARS-CoV-2 IgG antibody incidence over time in unvaccinated pediatric healthcare workers (pHCWs).

DESIGN

Prospective longitudinal cohort of unvaccinated pHCWs measuring incidence of new infection after initial prevalence was established at 4.1% with seropositive predominance in emergency department (ED)-based pHCWs. Serum samples were collected at follow-up visits to detect new SARS-CoV-2 seropositivity. Univariate analysis was performed to estimate different incidence rates between participant demographics, job, employment location and community risk factors. Anxiety levels about COVID-19 were collected. SARS-CoV-2 antibody decay post-infection, and neutralization antibodies were evaluated. Log-linear Poisson regression models were used to estimate incidence.

RESULTS

Of 642 initially enrolled, 390 pHCWs presented for at least one follow-up serology test after baseline analysis. Incidence of SARS-CoV-2 seropositivity was 8.2%. The seropositive cohort, like the negative one consisted mainly of females in non-ED settings and non-physician roles. There were no statistically significant differences in incidence across variables. Seropositive participants dropped antibody titers by 50% at 3 months. Neutralization antibodies correlated to SARs-CoV-2 binding antibodies (r=0.43,p<0.0001).

CONCLUSION

Incidence of seropositivity was 8.2%. Although seropositivity was higher among ED staff during early stages of the pandemic, this difference declined over time, likely due to universal adoption of personal protective equipment (PPE).

Validation of a screening panel for pediatric metabolic dysfunction-associated steatotic liver disease using metabolomics

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as NAFLD, is the most common liver disease in children. Liver biopsy remains the gold standard for diagnosis, although more efficient screening methods are needed. We previously developed a novel NAFLD screening panel in youth using machine learning applied to high-resolution metabolomics and clinical phenotype data. Our objective was to validate this panel in a separate cohort, which consisted of a combined cross-sectional sample of 161 children with stored frozen samples (75% male, 12.8±2.6 years of age, body mass index 31.0±7.0 kg/m2, 81% with MASLD, 58% Hispanic race/ethnicity).

METHODS

Clinical data were collected from all children, and high-resolution metabolomics was performed using their fasting serum samples. MASLD was assessed by MRI-proton density fat fraction or liver biopsy and cardiometabolic factors. Our previously developed panel included waist circumference, triglycerides, whole-body insulin sensitivity index, 3 amino acids, 2 phospholipids, dihydrothymine, and 2 unknowns. To improve feasibility, a simplified version without the unknowns was utilized in the present study. Since the panel was modified, the data were split into training (67%) and test (33%) sets to assess the validity of the panel.

RESULTS

Our present highest-performing modified model, with 4 clinical variables and 8 metabolomics features, achieved an AUROC of 0.92, 95% sensitivity, and 80% specificity for detecting MASLD in the test set.

CONCLUSIONS

Therefore, this panel has promising potential for use as a screening tool for MASLD in youth.

Using Real-World Electronic Health Record Data to Assess Chronic Disease Screening in Children: A Case Study of Non-Alcoholic Fatty Liver Disease

Background: Data sources for assessing pediatric chronic diseases and associated screening practices are rare. One example is non-alcoholic fatty liver disease (NAFLD), a common chronic liver disease prevalent among children with overweight and obesity. If undetected, NAFLD can cause liver damage. Guidelines recommend screening for NAFLD using alanine aminotransferase (ALT) tests in children ≥9 years with obesity or those with overweight and cardiometabolic risk factors. This study explores how real-world data from electronic health records (EHRs) can be used to study NAFLD screening and ALT elevation. Research Design: Using IQVIA's Ambulatory Electronic Medical Record database, we studied patients 2-19 years of age with body mass index ≥85th percentile. Using a 3-year observation period (January 1, 2019 to December 31, 2021), ALT results were extracted and assessed for elevation (≥1 ALT result ≥22.1 U/L for females and ≥25.8 U/L for males). Patients with liver disease (including NAFLD) or receiving hepatotoxic medications during 2017-2018 were excluded. Results: Among 919,203 patients 9-19 years of age, only 13% had ≥1 ALT result, including 14% of patients with obesity and 17% of patients with severe obesity. ALT results were identified for 5% of patients 2-8 years of age. Of patients with ALT results, 34% of patients 2-8 years of age and 38% of patients 9-19 years of age had ALT elevation. Males 9-19 years of age had a higher prevalence of ALT elevation than females (49% vs. 29%). Conclusions: EHR data offered novel insights into NAFLD screening: despite screening recommendations, ALT results among children with excess weight were infrequent. Among those with ALT results, ALT elevation was common, underscoring the importance of screening for early disease detection.

A multisociety Delphi consensus statement on new fatty liver disease nomenclature

The principal limitations of the terms NAFLD and NASH are the reliance on exclusionary confounder terms and the use of potentially stigmatising language. This study set out to determine if content experts and patient advocates were in favor of a change in nomenclature and/or definition. A modified Delphi process was led by three large pan-national liver associations. The consensus was defined a priori as a supermajority (67%) vote. An independent committee of experts external to the nomenclature process made the final recommendation on the acronym and its diagnostic criteria. A total of 236 panelists from 56 countries participated in 4 online surveys and 2 hybrid meetings. Response rates across the 4 survey rounds were 87%, 83%, 83%, and 78%, respectively. Seventy-four percent of respondents felt that the current nomenclature was sufficiently flawed to consider a name change. The terms "nonalcoholic" and "fatty" were felt to be stigmatising by 61% and 66% of respondents, respectively. Steatotic liver disease was chosen as an overarching term to encompass the various aetiologies of steatosis. The term steatohepatitis was felt to be an important pathophysiological concept that should be retained. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease. There was consensus to change the definition to include the presence of at least 1 of 5 cardiometabolic risk factors. Those with no metabolic parameters and no known cause were deemed to have cryptogenic steatotic liver disease. A new category, outside pure metabolic dysfunction-associated steatotic liver disease, termed metabolic and alcohol related/associated liver disease (MetALD), was selected to describe those with metabolic dysfunction-associated steatotic liver disease, who consume greater amounts of alcohol per week (140-350 g/wk and 210-420 g/wk for females and males, respectively). The new nomenclature and diagnostic criteria are widely supported and nonstigmatising, and can improve awareness and patient identification.

Nutrition assessment and MASH severity in children using the Healthy Eating Index

BACKGROUND

Pediatric metabolic-associated fatty liver disease (MAFLD) is a global health problem, with lifestyle modification as its major therapeutic strategy. Rigorous characterization of dietary content on MAFLD in children is lacking. We hypothesized an objectively measured healthier diet would positively modulate MAFLD.

METHODS

Diet was assessed using the Nutrition Data System for Research in children enrolled from 10 tertiary clinical centers to determine the Healthy Eating Index (HEI, 0-100) and individual food components.

RESULTS

In all, 119 children were included (13.3 ± 2.7 y), 80 (67%) male, 67 (18%) White, and 90 (76%) Hispanic, with an average body mass index Z-score of 2.2 ± 0.5. Diet was classified as low HEI < 47.94 (n = 39), mid HEI ≥ 47.94 and < 58.89 (n = 41), or high HEI ≥ 58.89 (n=39). Children with high HEI (healthier diet) had lower body weight (p = 0.005) and more favorable lipids. Mean serum triglycerides for low, mid, and high HEI were 163, 148, and 120 mg/dL, respectively; p = 0.04 mid versus high, p = 0.01 low versus high. Mean HDL was 38, 41 and 43 mg/dL; p = 0.02 low vs high. Less severe steatosis was noted with added sugar ≤ 10% of calories (p = 0.03). Higher lobular inflammation is associated with a higher percentage of calories from fat (OR (95% CI) = 0.95 (0.91-1.00), p = 0.04).

CONCLUSIONS

In children with MAFLD, high HEI is associated with lower body weight and more favorable lipids, while added sugar and fat intake has individual histologic features. Differential consumption of major dietary components may modify both metabolic risk factors and histologic liver injury, highlighting the importance of objective diet assessments in children with MAFLD.

A multisociety Delphi consensus statement on new fatty liver disease nomenclature

The principal limitations of the terms NAFLD and NASH are the reliance on exclusionary confounder terms and the use of potentially stigmatising language. This study set out to determine if content experts and patient advocates were in favour of a change in nomenclature and/or definition. A modified Delphi process was led by three large pan-national liver associations. The consensus was defined a priori as a supermajority (67%) vote. An independent committee of experts external to the nomenclature process made the final recommendation on the acronym and its diagnostic criteria. A total of 236 panellists from 56 countries participated in 4 online surveys and 2 hybrid meetings. Response rates across the 4 survey rounds were 87%, 83%, 83%, and 78%, respectively. Seventy-four percent of respondents felt that the current nomenclature was sufficiently flawed to consider a name change. The terms "nonalcoholic" and "fatty" were felt to be stigmatising by 61% and 66% of respondents, respectively. Steatotic liver disease was chosen as an overarching term to encompass the various aetiologies of steatosis. The term steatohepatitis was felt to be an important pathophysiological concept that should be retained. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease (MASLD). There was consensus to change the definition to include the presence of at least 1 of 5 cardiometabolic risk factors. Those with no metabolic parameters and no known cause were deemed to have cryptogenic steatotic liver disease. A new category, outside pure metabolic dysfunction-associated steatotic liver disease, termed metabolic and alcohol related/associated liver disease (MetALD), was selected to describe those with metabolic dysfunction-associated steatotic liver disease, who consume greater amounts of alcohol per week (140-350 g/wk and 210-420 g/wk for females and males, respectively). The new nomenclature and diagnostic criteria are widely supported and non-stigmatising, and can improve awareness and patient identification.

A multisociety Delphi consensus statement on new fatty liver disease nomenclature

The principal limitations of the terms NAFLD and NASH are the reliance on exclusionary confounder terms and the use of potentially stigmatising language. This study set out to determine if content experts and patient advocates were in favor of a change in nomenclature and/or definition. A modified Delphi process was led by three large pan-national liver associations. The consensus was defined a priori as a supermajority (67%) vote. An independent committee of experts external to the nomenclature process made the final recommendation on the acronym and its diagnostic criteria. A total of 236 panelists from 56 countries participated in 4 online surveys and 2 hybrid meetings. Response rates across the 4 survey rounds were 87%, 83%, 83%, and 78%, respectively. Seventy-four percent of respondents felt that the current nomenclature was sufficiently flawed to consider a name change. The terms "nonalcoholic" and "fatty" were felt to be stigmatising by 61% and 66% of respondents, respectively. Steatotic liver disease was chosen as an overarching term to encompass the various aetiologies of steatosis. The term steatohepatitis was felt to be an important pathophysiological concept that should be retained. The name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease. There was consensus to change the definition to include the presence of at least 1 of 5 cardiometabolic risk factors. Those with no metabolic parameters and no known cause were deemed to have cryptogenic steatotic liver disease. A new category, outside pure metabolic dysfunction-associated steatotic liver disease, termed metabolic and alcohol related/associated liver disease (MetALD), was selected to describe those with metabolic dysfunction-associated steatotic liver disease, who consume greater amounts of alcohol per week (140-350 g/wk and 210-420 g/wk for females and males, respectively). The new nomenclature and diagnostic criteria are widely supported and nonstigmatising, and can improve awareness and patient identification.

The Impact and Burden of Dietary Sugars on the Liver

NAFLD, or metabolic dysfunction-associated steatotic liver disease, has increased in prevalence hand in hand with the rise in obesity and increased free sugars in the food supply. The causes of NAFLD are genetic in origin combined with environmental drivers of the disease phenotype. Dietary intake of added sugars has been shown to have a major role in the phenotypic onset and progression of the disease. Simple sugars are key drivers of steatosis, likely through fueling de novo lipogenesis, the conversion of excess carbohydrates into fatty acids, but also appear to upregulate lipogenic metabolism and trigger hyperinsulinemia, another driver. NAFLD carries a clinical burden as it is associated with obesity, type 2 diabetes, metabolic syndrome, and cardiovascular disease. Patient quality of life is also impacted, and there is an enormous economic burden due to healthcare use, which is likely to increase in the coming years. This review aims to discuss the role of dietary sugar in NAFLD pathogenesis, the health and economic burden, and the promising potential of sugar reduction to improve health outcomes for patients with this chronic liver disease.

Development of Fibro-PeN, a clinical prediction model for moderate-to-severe fibrosis in children with nonalcoholic fatty liver disease

BACKGROUND AND AIMS

Liver fibrosis is common in children with NAFLD and is an important determinant of outcomes. High-performing noninvasive models to assess fibrosis in children are needed. The objectives of this study were to evaluate the performance of existing pediatric and adult fibrosis prediction models and to develop a clinical prediction rule for identifying moderate-to-severe fibrosis in children with NAFLD.

APPROACH AND RESULTS

We enrolled children with biopsy-proven NAFLD in the Nonalcoholic Steatohepatitis Clinical Research Network within 90 days of liver biopsy. We staged liver fibrosis in consensus using the Nonalcoholic Steatohepatitis Clinical Research Network scoring system. We evaluated existing pediatric and adult models for fibrosis and developed a new pediatric model using the least absolute shrinkage and selection operator with linear and spline terms for discriminating moderate-to-severe fibrosis from none or mild fibrosis. The model was internally validated with 10-fold cross-validation. We evaluated 1055 children with NAFLD, of whom 26% had moderate-to-severe fibrosis. Existing models performed poorly in classifying fibrosis in children, with area under the receiver operator curves (AUC) ranging from 0.57 to 0.64. In contrast, our new model, fibrosis in pediatric NAFLD was derived from fourteen common clinical variables and had an AUC of 0.79 (95% CI: 0.77-0.81) with 72% sensitivity and 76% specificity for identifying moderate-to-severe fibrosis.

CONCLUSION

Existing fibrosis prediction models have limited clinical utility in children with NAFLD. Fibrosis in pediatric NAFLD offers improved performance characteristics for risk stratification by identifying moderate-to-severe fibrosis in children with NAFLD.

Quality of dietary macronutrients is associated with glycemic outcomes in adults with cystic fibrosis

Objective

Poor diet quality contributes to metabolic dysfunction. This study aimed to gain a greater understanding of the relationship between dietary macronutrient quality and glucose homeostasis in adults with cystic fibrosis (CF).

Design

This was a cross-sectional study of N = 27 adults with CF with glucose tolerance ranging from normal (n = 9) to prediabetes (n = 6) to being classified as having cystic fibrosis-related diabetes (CFRD, n = 12). Fasted blood was collected for analysis of glucose, insulin, and C-peptide. Insulin resistance was assessed by Homeostatic Model Assessment for Insulin Resistance (HOMA2-IR). Subjects without known CFRD also underwent a 2-h oral glucose tolerance test. Three-day food records were used to assess macronutrient sources. Dietary variables were adjusted for energy intake. Statistical analyses included ANOVA, Spearman correlations, and multiple linear regression.

Results

Individuals with CFRD consumed less total fat and monounsaturated fatty acids (MUFA) compared to those with normal glucose tolerance (p < 0.05). In Spearman correlation analyses, dietary glycemic load was inversely associated with C-peptide (rho = -0.28, p = 0.05). Total dietary fat, MUFA, and polyunsaturated fatty acids (PUFA) were positively associated with C-peptide (rho = 0.39-0.41, all p < 0.05). Plant protein intake was inversely related to HOMA2-IR (rho = -0.28, p = 0.048). Associations remained significant after adjustment for age and sex.

Discussion

Improvements in diet quality are needed in people with CF. This study suggests that higher unsaturated dietary fat, higher plant protein, and higher carbohydrate quality were associated with better glucose tolerance indicators in adults with CF. Larger, prospective studies in individuals with CF are needed to determine the impact of diet quality on the development of CFRD.

Study protocol for a randomized, controlled trial using a novel, family-centered diet treatment to prevent nonalcoholic fatty liver disease in Hispanic children

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the leading liver disorder among U.S. children and is most prevalent among Hispanic children with obesity. Previous research has shown that reducing the consumption of free sugars (added sugars + naturally occurring sugars in fruit juice) can reverse liver steatosis in adolescents with NAFLD. This study aims to determine if a low-free sugar diet (LFSD) can prevent liver fat accumulation and NAFLD in high-risk children.

METHODS

In this randomized controlled trial, we will enroll 140 Hispanic children aged 6 to 9 years who are ≥50th percentile BMI and without a previous diagnosis of NAFLD. Participants will be randomly assigned to either an experimental (LFSD) or a control (usual diet + educational materials) group. The one-year intervention includes removal of foods high in free sugars from the home at baseline, provision of LFSD household groceries for the entire family (weeks 1-4, 12, 24, and 36), dietitian-guided family grocery shopping sessions (weeks 12, 24, and 36), and ongoing education and motivational interviewing to promote LFSD. Both groups complete assessment measures at baseline, 6, 12, 18, and 24 months. Primary study outcomes are percent hepatic fat at 12 months and incidence of clinically significant hepatic steatosis (>5%) + elevated liver enzymes at 24 months. Secondary outcomes include metabolic markers potentially mediating or moderating NAFLD pathogenesis.

DISCUSSION

This protocol describes the rationale, eligibility criteria, recruitment strategies, analysis plan as well as a novel dietary intervention design. Study results will inform future dietary guidelines for pediatric NAFLD prevention.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05292352.

Special Population: Pediatric Nonalcoholic Fatty Liver Disease

Pediatric nonalcoholic fatty liver disease represents the most common liver disease in children and has been shown to carry significant morbidity. Widespread heterogeneity of disease, as well as the limitation of indirect screening modalities, has made true prevalence of disease difficult to estimate as well as hindered ability to identify optimal prognostic factors in the pediatric population. Current therapeutic options are limited in pediatric patients with current mainstay of therapy, lifestyle modifications, has proven to have a limited efficacy in current clinical application. Current research remains needed in improved screening modalities, prognosticating techniques, and therapeutic options in the pediatric population.

Metabolome × Microbiome Changes Associated with a Diet-Induced Reduction in Hepatic Fat among Adolescent Boys

Dietary sugar reduction is one therapeutic strategy for improving nonalcoholic fatty liver disease (NAFLD), and the underlying mechanisms for this effect warrant further investigation. Here, we employed metabolomics and metagenomics to examine systemic biological adaptations associated with dietary sugar restriction and (subsequent) hepatic fat reductions in youth with NAFLD. Data/samples were from a randomized controlled trial in adolescent boys (11-16 years, mean ± SD: 13.0 ± 1.9 years) with biopsy-proven NAFLD who were either provided a low free-sugar diet (LFSD) (n = 20) or consumed their usual diet (n = 20) for 8 weeks. Plasma metabolomics was performed on samples from all 40 participants by coupling hydrophilic interaction liquid chromatography (HILIC) and C18 chromatography with mass spectrometry. In a sub-sample (n = 8 LFSD group and n = 10 usual diet group), 16S ribosomal RNA (rRNA) sequencing was performed on stool to examine changes in microbial composition/diversity. The diet treatment was associated with differential expression of 419 HILIC and 205 C18 metabolite features (p < 0.05), which were enriched in amino acid pathways, including methionine/cysteine and serine/glycine/alanine metabolism (p < 0.05), and lipid pathways, including omega-3 and linoleate metabolism (p < 0.05). Quantified metabolites that were differentially changed in the LFSD group, compared to usual diet group, and representative of these enriched metabolic pathways included increased serine (p = 0.001), glycine (p = 0.004), 2-aminobutyric acid (p = 0.012), and 3-hydroxybutyric acid (p = 0.005), and decreased linolenic acid (p = 0.006). Microbiome changes included an increase in richness at the phylum level and changes in a few genera within Firmicutes. In conclusion, the LFSD treatment, compared to usual diet, was associated with metabolome and microbiome changes that may reflect biological mechanisms linking dietary sugar restriction to a therapeutic decrease in hepatic fat. Studies are needed to validate our findings and test the utility of these "omics" changes as response biomarkers.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease

BACKGROUND AND AIMS

Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis.

APPROACH AND RESULTS

A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS.

CONCLUSIONS

Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Concordance of SARS-CoV-2 Results in Self-collected Nasal Swabs vs Swabs Collected by Health Care Workers in Children and Adolescents

IMPORTANCE

Despite the expansion of SARS-CoV-2 testing, available tests have not received Emergency Use Authorization for performance with self-collected anterior nares (nasal) swabs from children younger than 14 years because the effect of pediatric self-swabbing on SARS-CoV-2 test sensitivity is unknown.

OBJECTIVE

To characterize the ability of school-aged children to self-collect nasal swabs for SARS-CoV-2 testing compared with collection by health care workers.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of 197 symptomatic children and adolescents aged 4 to 14 years old. Individuals were recruited based on results of testing in the Children's Healthcare of Atlanta system from July to August 2021.

EXPOSURES

Children and adolescents were given instructional material consisting of a short instructional video and a handout with written and visual steps for self-swab collection. Participants first provided a self-collected nasal swab. Health care workers then collected a second specimen.

MAIN OUTCOMES AND MEASURES

The primary outcome was SARS-CoV-2 detection and relative quantitation by cycle threshold (Ct) in self- vs health care worker-collected nasal swabs when tested with a real-time reverse transcriptase-polymerase chain reaction test with Emergency Use Authorization.

RESULTS

Among the study participants, 108 of 194 (55.7%) were male and the median age was 9 years (IQR, 6-11). Of the 196 participants, 87 (44.4%) tested positive for SARS-CoV-2 and 105 (53.6%) tested negative by both self- and health care worker-collected swabs. Two children tested positive by self- or health care worker-collected swab alone; 1 child had an invalid health care worker swab. Compared with health care worker-collected swabs, self-collected swabs had 97.8% (95% CI, 94.7%-100.0%) and 98.1% (95% CI, 95.6%-100.0%) positive and negative percent agreement, respectively, and SARS-CoV-2 Ct values did not differ significantly between groups (mean [SD] Ct, self-swab: 26.7 [5.4] vs health care worker swab: 26.3 [6.0]; P = .65).

CONCLUSIONS AND RELEVANCE

After hearing and seeing simple instructional materials, children and adolescents aged 4 to 14 years self-collected nasal swabs that closely agreed on SARS-CoV-2 detection with swabs collected by health care workers.

Risk of variceal hemorrhage and pretransplant mortality in children with biliary atresia

BACKGROUND AND AIMS

The natural history of gastroesophageal variceal hemorrhage (VH) in biliary atresia (BA) is not well characterized. We analyzed risk factors, incidence, and outcomes of VH in a longitudinal multicenter study.

APPROACH AND RESULTS

Participants enrolled in either an incident (Prospective Database of Infants with Cholestasis [PROBE]) or prevalent (Biliary Atresia Study of Infants and Children [BASIC]) cohort of BA were included. Variceal hemorrhage (VH) was defined based on gastrointestinal bleeding in the presence of varices accompanied by endoscopic or nontransplant surgical intervention. Cumulative incidence of VH and transplant-free survival was compared based on features of portal hypertension (e.g., splenomegaly, thrombocytopenia) and clinical parameters at baseline in each cohort (PROBE: 1.5 to 4.5 months after hepatoportoenterostomy [HPE]; BASIC: at enrollment > 3 years of age). Analyses were conducted on 869 children with BA enrolled between June 2004 and December 2020 (521 in PROBE [262 (51%) with a functioning HPE] and 348 in BASIC). The overall incidence of first observed VH at 5 years was 9.4% (95% CI: 7.0-12.4) in PROBE and 8.0% (5.2-11.5) in BASIC. Features of portal hypertension, platelet count, total bilirubin, aspartate aminotransferase (AST), albumin, and AST-to-platelet ratio index at baseline were associated with an increased risk of subsequent VH in both cohorts. Transplant-free survival at 5 years was 45.1% (40.5-49.6) in PROBE and 79.2% (74.1-83.4) in BASIC. Two (2.5%) of 80 participants who had VH died, whereas 10 (12.5%) underwent transplant within 6 weeks of VH.

CONCLUSIONS

The low risk of VH and associated mortality in children with BA needs to be considered in decisions related to screening for varices and primary prophylaxis of VH.

Randomized placebo-controlled trial of losartan for pediatric NAFLD

BACKGROUND AND AIMS

To date, no pharmacotherapy exists for pediatric NAFLD. Losartan, an angiotensin II receptor blocker, has been proposed as a treatment due to its antifibrotic effects.

APPROACH AND RESULTS

The Nonalcoholic Steatohepatitis Clinical Research Network conducted a multicenter, double-masked, placebo-controlled, randomized clinical trial in children with histologically confirmed NAFLD at 10 sites (September 2018 to April 2020). Inclusion criteria were age 8-17 years, histologic NAFLD activity score ≥ 3, and serum alanine aminotransferase (ALT) ≥ 50 U/l. Children received 100 mg of losartan or placebo orally once daily for 24 weeks. The primary outcome was change in ALT levels from baseline to 24 weeks, and the preset sample size was n = 110. Treatment effects were assessed using linear regression of change in treatment group adjusted for baseline value. Eighty-three participants (81% male, 80% Hispanic) were randomized to losartan (n = 43) or placebo (n = 40). During an enrollment pause, necessitated by the 2019 coronavirus pandemic, an unplanned interim analysis showed low probability (7%) of significant group difference. The Data and Safety Monitoring Board recommended early study termination. Baseline characteristics were similar between groups. The 24-week change in ALT did not differ significantly between losartan versus placebo groups (adjusted mean difference: 1.1 U/l; 95% CI = -30.6, 32.7; p = 0.95), although alkaline phosphatase decreased significantly in the losartan group (adjusted mean difference: -23.4 U/l; 95% CI = -41.5, -5.3; p = 0.01). Systolic blood pressure decreased in the losartan group but increased in placebo (adjusted mean difference: -7.5 mm Hg; 95% CI = -12.2, -2.8; p = 0.002). Compliance by pill counts and numbers and types of adverse events did not differ by group.

CONCLUSIONS

Losartan did not significantly reduce ALT in children with NAFLD when compared with placebo.

Association of Prenatal Exposure to Endocrine-Disrupting Chemicals With Liver Injury in Children

Importance

Prenatal exposures to endocrine-disrupting chemicals (EDCs) may increase the risk for liver injury in children; however, human evidence is scarce, and previous studies have not considered potential EDC-mixture effects. Furthermore, the association between prenatal EDC exposure and hepatocellular apoptosis in children has not been studied previously.

Objective

To investigate associations of prenatal exposure to EDC mixtures with liver injury risk and hepatocellular apoptosis in childhood.

Design, Setting, and Participants

This prospective cohort study used data collected from April 1, 2003, to February 26, 2016, from mother-child pairs from the Human Early-Life Exposome project, a collaborative network of 6 ongoing, population-based prospective birth cohort studies from 6 European countries (France, Greece, Lithuania, Norway, Spain, and the UK). Data were analyzed from April 1, 2021, to January 31, 2022.

Exposures

Three organochlorine pesticides, 5 polychlorinated biphenyls, 2 polybrominated diphenyl ethers (PBDEs), 3 phenols, 4 parabens, 10 phthalates, 4 organophosphate pesticides, 5 perfluoroalkyl substances, and 9 metals.

Main Outcomes and Measures

Child serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (GGT), and CK-18 were measured at 6 to 11 years of age. Risk for liver injury was defined as having ALT, AST, and/or GGT levels above the 90th percentile. Associations of liver injury or cytokeratin 18 (CK-18) levels with each chemical group among the 45 EDCs measured in maternal blood or urine samples collected in pregnancy were estimated using 2 complimentary exposure-mixture methods: bayesian weighted quantile sum (BWQS) and bayesian kernel machine regression.

Results

The study included 1108 mothers (mean [SD] age at birth, 31.0 [4.7] years) and their singleton children (mean [SD] age at liver assessment, 8.2 [1.6] years; 598 [54.0%] boys). Results of the BWQS method indicated increased odds of liver injury per exposure-mixture quartile increase for organochlorine pesticides (odds ratio [OR], 1.44 [95% credible interval (CrI), 1.21-1.71]), PBDEs (OR, 1.57 [95% CrI, 1.34-1.84]), perfluoroalkyl substances (OR, 1.73 [95% CrI, 1.45-2.09]), and metals (OR, 2.21 [95% CrI, 1.65-3.02]). Decreased odds of liver injury were associated with high-molecular-weight phthalates (OR, 0.74 [95% CrI, 0.60-0.91]) and phenols (OR, 0.66 [95% CrI, 0.54-0.78]). Higher CK-18 levels were associated with a 1-quartile increase in polychlorinated biphenyls (β, 5.84 [95% CrI, 1.69-10.08] IU/L) and PBDEs (β, 6.46 [95% CrI, 3.09-9.92] IU/L). Bayesian kernel machine regression showed associations in a similar direction as BWQS for all EDCs and a nonlinear association between phenols and CK-18 levels.

Conclusions and Relevance

With a combination of 2 state-of-the-art exposure-mixture approaches, consistent evidence suggests that prenatal exposures to EDCs are associated with higher risk for liver injury and CK-18 levels and constitute a potential risk factor for pediatric nonalcoholic fatty liver disease.

Comparison of Mid-turbinate Nasal Swabs, Saliva and Nasopharyngeal Swabs for SARSCoV-2 Reverse Transcription Polymerase Chain Reaction Testing in Pediatric Outpatients

CONTEXT.–

Diagnostic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in symptomatic and asymptomatic children remains integral to care, particularly for supporting return to and attendance in schools. The concordance of SARS-CoV-2 detection in children using various specimen types has not been widely studied.

OBJECTIVE.–

To compare three sample types for SARS-CoV-2 PCR testing in children collected and tested at a single facility.

DESIGN.–

We prospectively recruited 142 symptomatic and asymptomatic children into a sample comparison study performed in a single healthcare system. Each child provided self-collected saliva, and a trained healthcare provider collected a mid-turbinate nasal swab and nasopharyngeal (NP) swab. Specimens were assayed within 24 hours of collection using reverse transcriptase-polymerase chain reaction (RT-PCR) to detect SARS-CoV-2 on a single testing platform.

RESULTS.–

Concurrently collected saliva and mid-turbinate swabs had >95% positive agreement with NP swabs when obtained within 10 days of symptom onset. Positive agreement of saliva and mid-turbinate samples collected from children with symptom onset >10 days prior, or without symptoms, was 82% compared to NP swab samples. Cycle threshold (Ct) values for mid-turbinate nasal samples more closely correlated with Ct values from NP samples than saliva sample Ct values.

CONCLUSIONS.–

These findings suggest that all three sample types from children are useful for SARS-CoV-2 diagnostic testing by RT-PCR, and that concordance is greatest when the child has symptoms of coronavirus disease 2019 (COVID-19) within the past 10 days. This study provides scientific justification for utilizing sample types other than the NP swab for SARS-CoV-2 testing in pediatric populations.

Predictive value of isolated symptoms for diagnosis of SARS-CoV-2 infection in children tested during peak circulation of the delta variant

Background

Coronavirus disease 2019 (COVID-19) testing policies for symptomatic children attending US schools or daycare vary, and whether isolated symptoms should prompt testing is unclear. We evaluated children presenting for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing to determine if the likelihood of having a positive SARS-CoV-2 test differed between participants with 1 symptom vs ≥2 symptoms, and to examine the predictive capability of isolated symptoms.

Methods

Participants aged <18 years presenting for clinical SARS-CoV-2 molecular testing in 6 sites in urban/suburban/rural Georgia (July–October, 2021; Delta variant predominant) were queried about individual symptoms. Participants were classified into 3 groups: asymptomatic, 1 symptom only, or ≥2 symptoms. SARS-CoV-2 test results and clinical characteristics of the 3 groups were compared. Sensitivity, specificity, positive predictive values (PPVs), and negative predictive values (NPVs) for isolated symptoms were calculated by fitting a saturated Poisson model.

Results

Of 602 participants, 21.8% tested positive and 48.7% had a known or suspected close contact. Children reporting 1 symptom (n = 82; odds ratio [OR], 6.00 [95% confidence interval {CI}, 2.70–13.33]) and children reporting ≥2 symptoms (n = 365; OR, 5.25 [95% CI, 2.66–10.38]) were significantly more likely to have a positive COVID-19 test than asymptomatic children (n = 155), but they were not significantly different from each other (OR, 0.88 [95% CI, .52–1.49]). Sensitivity and PPV were highest for isolated fever (33% and 57%, respectively), cough (25% and 32%), and sore throat (21% and 45%); headache had low sensitivity (8%) but higher PPV (33%). Sensitivity and PPV of isolated congestion/rhinorrhea were 8% and 9%, respectively.

Conclusions

With high Delta variant prevalence, children with isolated symptoms were as likely as those with multiple symptoms to test positive for COVID-19. Isolated fever, cough, sore throat, or headache, but not congestion/rhinorrhea, offered the highest predictive value.

Variation in Alanine Aminotransferase in Children with Non-Alcoholic Fatty Liver Disease

Background: Pediatric non-alcoholic fatty liver disease (NAFLD) is a major public health concern. Aminotransferase (ALT) is frequently used for screening and monitoring, but few studies have reported typical patterns of ALT elevation in children. Methods: TARGET-NASH is a real-world longitudinal observational cohort of patients with NAFLD receiving care across the United States. Analyses included children enrolled between 1 August 2016, and 12 October 2020, with at least one ALT measurement after enrollment. Peak ALT was based on the first and last available record and categorized into clinical cut points: <70 IU/L, >70−<250 IU/L, and >250 IU/L. A chi-squared test was used to compare differences in proportions, and a Kruskal−Wallis test was used to compare the medians and distributions of continuous responses. Results: Analyses included 660 children with a median age of 13 years. Of the 660, a total of 187 had undergone a biopsy and were more likely to be Hispanic or Latino (67% vs. 57%, p = 0.02) and to have cirrhosis (10% vs. 1%, p < 0.001). The highest ALT scores ranged from 28 U/L to 929 U/L; however, these scores varied across time. The prevalence of cirrhosis or any liver fibrosis stage was most common among children with a peak ALT > 70 U/L. Conclusions: Large variability was seen in ALT among children, including many values > 250 U/L. Higher levels of ALT were associated with increased prevalence of comorbidities and more advanced stages of NAFLD. These findings support an increased need for therapeutics and disease severity assessment in children with peak ALT > 70 U/L.

Dietary sugar restriction reduces hepatic de novo lipogenesis in adolescent boys with fatty liver disease

BACKGROUNDHepatic de novo lipogenesis (DNL) is elevated in nonalcoholic fatty liver disease (NAFLD). Improvements in hepatic fat by dietary sugar reduction may be mediated by reduced DNL, but data are limited, especially in children. We examined the effects of 8 weeks of dietary sugar restriction on hepatic DNL in adolescents with NAFLD and correlations between DNL and other metabolic outcomes.METHODSAdolescent boys with NAFLD (n = 29) participated in an 8-week, randomized controlled trial comparing a diet low in free sugars versus their usual diet. Hepatic DNL was measured as percentage contribution to plasma triglyceride palmitate using a 7-day metabolic labeling protocol with heavy water. Hepatic fat was measured by magnetic resonance imaging-proton density fat fraction.RESULTSHepatic DNL was significantly decreased in the treatment group (from 34.6% to 24.1%) versus the control group (33.9% to 34.6%) (adjusted week 8 mean difference: -10.6% [95% CI: -19.1%, -2.0%]), which was paralleled by greater decreases in hepatic fat (25.5% to 17.9% vs. 19.5% to 18.8%) and fasting insulin (44.3 to 34.7 vs. 35.5 to 37.0 μIU/mL). Percentage change in DNL during the intervention correlated significantly with changes in free-sugar intake (r = 0.48, P = 0.011), insulin (r = 0.40, P = 0.047), and alanine aminotransferase (ALT) (r = 0.39, P = 0.049), but not hepatic fat (r = 0.13, P = 0.532).CONCLUSIONOur results suggest that dietary sugar restriction reduces hepatic DNL and fasting insulin, in addition to reductions in hepatic fat and ALT, among adolescents with NAFLD. These results are consistent with the hypothesis that hepatic DNL is a critical metabolic abnormality linking dietary sugar and NAFLD.TRIAL REGISTRYClinicalTrials.gov NCT02513121.FUNDINGThe Nutrition Science Initiative (made possible by gifts from the Laura and John Arnold Foundation, Ambrose Monell Foundation, and individual donors), the UCSD Altman Clinical and Translational Research Institute, the NIH, Children's Healthcare of Atlanta and Emory University's Children's Clinical and Translational Discovery Core, Children's Healthcare of Atlanta and Emory University Pediatric Biostatistical Core, the Georgia Clinical and Translational Science Alliance, and the NIH National Institute of Diabetes, Digestive, and Kidney Disease.

Microbial metabolite delta-valerobetaine is a diet-dependent obesogen

Obesity and obesity-related metabolic disorders are linked to the intestinal microbiome. However, the causality of changes in the microbiome-host interaction affecting energy metabolism remains controversial. Here, we show the microbiome-derived metabolite δ-valerobetaine (VB) is a diet-dependent obesogen that is increased with phenotypic obesity and is correlated with visceral adipose tissue mass in humans. VB is absent in germ-free mice and their mitochondria but present in ex-germ-free conventionalized mice and their mitochondria. Mechanistic studies in vivo and in vitro show VB is produced by diverse bacterial species and inhibits mitochondrial fatty acid oxidation through decreasing cellular carnitine and mitochondrial long-chain acyl-coenzyme As. VB administration to germ-free and conventional mice increases visceral fat mass and exacerbates hepatic steatosis with a western diet but not control diet. Thus, VB provides a molecular target to understand and potentially manage microbiome-host symbiosis or dysbiosis in diet-dependent obesity.

PRO-C3, a Serological Marker of Fibrosis, During Childhood and Correlations With Fibrosis in Pediatric NAFLD

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease in children and may lead to cirrhosis requiring liver transplant. Thus, prompt diagnosis of advanced fibrosis is essential. Our objectives were to examine PRO-C3 (a neo-epitope pro-peptide of type III collagen formation) levels across childhood/adolescence and associations with advanced fibrosis in pediatric NAFLD. This cross-sectional study included 88 children and adolescents with biopsy-proven NAFLD (mean age: 13.9 ± 2.9 years, 71% male) and 65 healthy participants (11.8 ± 4.5 years, 38% male). PRO-C3, and the bone remodeling biomarkers C-terminal telopeptide of type I collagen (CTX-I; bone resorption) and osteocalcin (N-MID; bone formation), were measured in serum by enzyme-linked immunosorbent assay. Fibrosis was assessed by liver biopsy in participants with NAFLD, who were categorized as having advanced (Ishak score ≥ 3) or none/mild fibrosis (Ishak score ≤ 2). Overall, PRO-C3 was similar in participants with NAFLD (median [interquartile range]: 20.6 [15.8, 25.9] ng/mL) versus healthy participants (19.0 [13.8, 26.0] ng/mL), but was significantly lower in older adolescents ≥ 15 years old (16.4 [13.0, 21.2] ng/mL) compared with children ≤ 10 years old (22.9 [18.1, 28.4] ng/mL; P < 0.001) or 11-14 years old (22.4 [18.3, 31.2] ng/mL; P < 0.001). PRO-C3 was also directly correlated with levels of CTX-I and N-MID (r = 0.64 and r = 0.62, respectively; both P < 0.001). Among participants with NAFLD, PRO-C3 was higher in those with advanced fibrosis (median [IQR]: 28.5 [21.6, 37.6]) compared with none/mild fibrosis (20.3 [18.2, 22.8]; P = 0.020) in models adjusted for age, sex, and body mass index z-score. However, associations were attenuated after additionally adjusting for bone-remodeling CTX-I (P = 0.09) or N-MID (P = 0.08). Conclusion: Collectively, these findings show that PRO-C3 levels are higher in children with advanced fibrosis in NAFLD, but are also influenced by age and pubertal growth spurt, assessed by bone remodeling biomarkers, and therefore may not be a reliable biomarker for liver fibrosis in pediatric NAFLD until late adolescence.

Correlation of SARS-CoV-2 Subgenomic RNA with Antigen Detection in Nasal Midturbinate Swab Specimens

Among symptomatic outpatients, subgenomic RNA of severe acute respiratory syndrome coronavirus 2 in nasal midturbinate swab specimens was concordant with antigen detection but remained detectable in 13 (82.1%) of 16 nasopharyngeal swab specimens from antigen-negative persons. Subgenomic RNA in midturbinate swab specimens might be useful for routine diagnostics to identify active virus replication.

In Utero Exposure to Mercury Is Associated With Increased Susceptibility to Liver Injury and Inflammation in Childhood

BACKGROUND AND AIMS

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent cause of liver disease in children. Mercury (Hg), a ubiquitous toxic metal, has been proposed as an environmental factor contributing to toxicant-associated fatty liver disease.

APPROACH AND RESULTS

We investigated the effect of prenatal exposure to Hg on childhood liver injury by combining epidemiological results from a multicenter mother-child cohort with complementary in vitro experiments on monocyte cells that are known to play a key role in liver immune homeostasis and NAFLD. We used data from 872 mothers and their children (median age, 8.1 years; interquartile range [IQR], 6.5-8.7) from the European Human Early-Life Exposome cohort. We measured Hg concentration in maternal blood during pregnancy (median, 2.0 μg/L; IQR, 1.1-3.6). We also assessed serum levels of alanine aminotransferase (ALT), a common screening tool for pediatric NAFLD, and plasma concentrations of inflammation-related cytokines in children. We found that prenatal Hg exposure was associated with a phenotype in children that was characterized by elevated ALT (≥22.1 U/L for females and ≥25.8 U/L for males) and increased concentrations of circulating IL-1β, IL-6, IL-8, and TNF-α. Consistently, inflammatory monocytes exposed in vitro to a physiologically relevant dose of Hg demonstrated significant up-regulation of genes encoding these four cytokines and increased concentrations of IL-8 and TNF-α in the supernatants.

CONCLUSIONS

These findings suggest that developmental exposure to Hg can contribute to inflammation and increased NAFLD risk in early life.

Longitudinal associations of total and trunk fat in childhood and adolescence and risk of hepatic steatosis at 24 years

BACKGROUND

The importance of body fat distribution in the development of nonalcoholic fatty liver disease (NAFLD) is unclear.

OBJECTIVE

To examine whether total and truncal fat deposition patterns in childhood/adolescence are associated with NAFLD risk at 24 years.

METHODS

Data were from 1657 participants in the Avon Longitudinal Study of Parents and Children. Transient elastography was used to assess hepatic steatosis (low/moderate/severe) at 24 years and dual-energy X-ray absorptiometry was used to assess total body fat percent (TBF%) and trunk fat percent (TrF%) at 9, 13, 15, 17, and/or 24 years. Linear mixed models were constructed with quadratic age to examine trajectories of TBF% and TrF% by steatosis at 24 years, adjusting for confounders.

RESULTS

In both sexes, TBF% trajectories from 9 to 24 years followed a similar pattern based on steatosis group (P = .83 for boys and P = .14 for girls for age² *steatosis fixed effect). However, at all ages TBF% was higher for moderate/severe vs low steatosis at 24 years (P < .05). In contrast, TrF% trajectories diverged based on steatosis group (P = .001 for boys and P = .0002 for girls for age² *steatosis fixed effect), such that, in both sexes, participants with moderate/severe steatosis at 24 yrs exhibited less decline in TrF% from adolescence to adulthood compared to participants with low steatosis at 24 yrs. Similar to TBF%, TrF% was higher at nearly all ages for moderate/severe vs low steatosis. Results were similar after adjusting for BMI category at each age, except in boys some differences for TrF% were attenuated.

CONCLUSIONS

These findings suggest that sex-specific body fat distribution patterns in childhood/adolescence may help to identify those at risk of developing NAFLD in adulthood.

Impact of repeated nasal sampling on detection and quantification of SARS-CoV-2

The impact of repeated sample collection on COVID-19 test performance is unknown. The FDA and CDC currently recommend the primary collection of diagnostic samples to minimize the perceived risk of false-negative findings. We therefore evaluated the association between repeated sample collection and test performance among 325 symptomatic patients undergoing COVID-19 testing in Atlanta, GA. High concordance was found between consecutively collected mid-turbinate samples with both molecular (n = 74, 100% concordance) and antigen-based (n = 147, 97% concordance, kappa = 0.95, CI = 0.88–1.00) diagnostic assays. Repeated sample collection does not decrease COVID-19 test performance, demonstrating that multiple samples can be collected for assay validation and clinical diagnosis.

Multidisciplinary assessment of the Abbott BinaxNOW SARS-CoV-2 point-of-care antigen test in the context of emerging viral variants and self-administration

While there has been significant progress in the development of rapid COVID-19 diagnostics, as the pandemic unfolds, new challenges have emerged, including whether these technologies can reliably detect the more infectious variants of concern and be viably deployed in non-clinical settings as "self-tests". Multidisciplinary evaluation of the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW, a widely used rapid antigen test, included limit of detection, variant detection, test performance across different age-groups, and usability with self/caregiver-administration. While BinaxNOW detected the highly infectious variants, B.1.1.7 (Alpha) first identified in the UK, B.1.351 (Beta) first identified in South Africa, P.1 (Gamma) first identified in Brazil, B.1.617.2 (Delta) first identified in India and B.1.2, a non-VOC, test sensitivity decreased with decreasing viral loads. Moreover, BinaxNOW sensitivity trended lower when devices were performed by patients/caregivers themselves compared to trained clinical staff, despite universally high usability assessments following self/caregiver-administration among different age groups. Overall, these data indicate that while BinaxNOW accurately detects the new viral variants, as rapid COVID-19 tests enter the home, their already lower sensitivities compared to RT-PCR may decrease even more due to user error.

Associations of maternal diet and nutritional status with offspring hepatic steatosis in the Avon longitudinal study of parents and children

BACKGROUND

Priming for cardiometabolic diseases, including non-alcoholic fatty liver disease (NAFLD), is hypothesized to begin in utero. The primary objective of this study is to determine whether there is an association between maternal nutritional status and offspring NAFLD.

METHODS

Data come from the Avon Longitudinal Study of Parents and Children (ALSPAC) in the UK. The analytic sample included 3353 participants who had maternal information on pre-pregnancy BMI, gestational weight gain, diabetes, and free sugar intake as percent of total energy and were assessed for mild-severe hepatic steatosis at 24 years by transient elastography (controlled attenuation parameter score ≥ 248 dB/m). Multiple logistic regression was used to evaluate the association between maternal factors and offspring hepatic steatosis at 24 years.

RESULTS

In confounder-adjusted models the independent associations for each maternal factor with mild to severe vs low hepatic steatosis at 24 years were: pre-pregnancy overweight (OR: 1.84, 95%CL: 1.43-2.38) or obesity (OR: 2.73, 95%CL: 1.84-4.03), more than recommended gestational weight gain (OR: 1.30, 95%CL: 1.04-1.64), diabetes (OR: 1.39, 95%CI: 0.87, 2.21), and high free sugar intake during pregnancy (OR: 1.04, 95% CI: 0.82, 1.33). These associations were largely mediated by BMI at 24 years, but not by birthweight or breastfeeding.

CONCLUSIONS

Our results suggest that maternal nutritional status is associated with the development of NAFLD in their adult offspring, although the relationship is largely mediated by offspring BMI in adulthood.

Prenatal and childhood exposure to air pollution and traffic and the risk of liver injury in European children

Nonalcoholic fatty liver disease is the most prevalent pediatric chronic liver disease. Experimental studies suggest effects of air pollution and traffic exposure on liver injury. We present the first large-scale human study to evaluate associations of prenatal and childhood air pollution and traffic exposure with liver injury.

METHODS

Study population included 1,102 children from the Human Early Life Exposome project. Established liver injury biomarkers, including alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and cytokeratin-18, were measured in serum between ages 6-10 years. Air pollutant exposures included nitrogen dioxide, particulate matter <10 μm (PM10), and <2.5 μm. Traffic measures included traffic density on nearest road, traffic load in 100-m buffer, and inverse distance to nearest road. Exposure assignments were made to residential address during pregnancy (prenatal) and residential and school addresses in year preceding follow-up (childhood). Childhood indoor air pollutant exposures were also examined. Generalized additive models were fitted adjusting for confounders. Interactions by sex and overweight/obese status were examined.

RESULTS

Prenatal and childhood exposures to air pollution and traffic were not associated with child liver injury biomarkers. There was a significant interaction between prenatal ambient PM10 and overweight/obese status for alanine aminotransferase, with stronger associations among children who were overweight/obese. There was no evidence of interaction with sex.

CONCLUSION

This study found no evidence for associations between prenatal or childhood air pollution or traffic exposure with liver injury biomarkers in children. Findings suggest PM10 associations maybe higher in children who are overweight/obese, consistent with the multiple-hits hypothesis for nonalcoholic fatty liver disease pathogenesis.

Patient Determinants for Histologic Diagnosis of NAFLD in the Real World: A TARGET-NASH Study

Much of the current data on nonalcoholic fatty liver disease (NAFLD) are derived from biopsy-based studies that may introduce ascertainment and selection bias. Selection of patients for liver biopsy has implications for clinical practice and the reported epidemiology of NAFLD. The aim of this study was to determine patient factors predictive of histologic versus empiric clinical diagnosis of NAFLD in real-world practice. Adults from TARGET-NASH were included in this study. Descriptive statistics are provided for the cohort and compare the characteristics of histologic NAFLD versus patients with clinically diagnosed NAFLD, followed by logistic regression and machine-learning models to describe predictors of liver biopsy. The records of 3,474 subjects were analyzed; median age was 59 years, 59% were female, 75% were White, and median body mass index was 32 kg/m2. Using histologic and/or clinical criteria, a diagnosis of nonalcoholic steatohepatitis was made in 37%, and cirrhosis in 33%. Comorbid conditions included cardiovascular disease (19%), mental health diagnoses (49%), and osteoarthritis (10%). Predictors of a biopsy diagnosis included White race, female sex, diabetes, and elevated alanine aminotransferase (ALT). ALT increased the odds of liver biopsy by 14% per 10-point rise. Machine-learning analyses showed non-White patients with ALT <69 had only a 0.06 probability of undergoing liver biopsy. ALT was the dominant variable that determined liver biopsy. Conclusions: In this real-world cohort of patients with NAFLD, two-thirds of patients did not have a liver biopsy. These patients were more likely to be non-White, older, with a normal ALT, showing potential gaps in or knowledge about this population.

Associations between Free Sugar and Sugary Beverage Intake in Early Childhood and Adult NAFLD in a Population-Based UK Cohort

(1) Background: High sugar intake is prevalent among children and is associated with non-alcoholic fatty liver disease (NAFLD). The purpose of this study is to determine if a high intake of free sugars and sugary beverages (SB) in childhood is associated with NAFLD in adulthood; (2) Methods: At 24 years, 3095 participants were assessed for severe hepatic steatosis (controlled attenuation parameter >280 dB/m) and had dietary data collected via a food frequency questionnaire at age three years. Multiple logistic regression models adjusted for total energy intake, potential confounders, and a mediator (offspring body mass index (BMI) at 24 years); (3) Results: Per quintile increase of free sugar intake association with severe hepatic steatosis at 24 years after adjusting for total energy was odds ratio (OR):1.07 (95% CL: 0.99-1.17). Comparing the lowest vs. the highest free sugar consumers, the association was OR:1.28 (95% CL: 0.88-1.85) and 1.14 (0.72, 1.82) after full adjustment. The OR for high SB consumption (>2/day) compared to <1/day was 1.23 (95% CL: 0.82-1.84) and OR: 0.98 (95% CL: 0.60-1.60) after full adjustment; (4) Conclusions: High free sugar and SB intake at three years were positively but weakly associated with severe hepatic steatosis at 24 years. These associations were completely attenuated after adjusting for confounders and 24-year BMI.

Prevalence of SARS-CoV-2 antibodies in pediatric healthcare workers

Objectives

To determine SARS-CoV-2-antibody prevalence in pediatric healthcare workers (pHCWs).

Design

Baseline prevalence of anti-SARS-CoV-2-IgG was assessed in a prospective cohort study from a large pediatric healthcare facility. Prior SARS-CoV-2 testing history, potential risk factors and anxiety level about COVID-19 were determined. Prevalence difference between emergency department (ED)-based and non-ED-pHCWs was modeled controlling for those covariates. Chi-square test-for-trend was used to examine prevalence by month of enrollment.

Results

Most of 642 pHCWs enrolled were 31-40years, female and had no comorbidities. Half had children in their home, 49% had traveled, 42% reported an illness since January, 31% had a known COVID-19 exposure, and 8% had SARS-CoV-2 PCR testing. High COVID-19 pandemic anxiety was reported by 71%. Anti-SARS-CoV-2-IgG prevalence was 4.1%; 8.4% among ED versus 2.0% among non-ED pHCWs (p < 0.001). ED-work location and known COVID-19 exposure were independent risk factors. 31% of antibody-positive pHCWs reported no symptoms. Prevalence significantly (p < 0.001) increased from 3.0% in April–June to 12.7% in July–August.

Conclusions

Anti-SARS-CoV-2-IgG prevalence was low in pHCWs but increased rapidly over time. Both working in the ED and exposure to a COVID-19-positive contact were associated with antibody-seropositivity. Ongoing universal PPE utilization is essential. These data may guide vaccination policies to protect front-line workers.

Alanine Aminotransferase and Gamma-Glutamyl Transpeptidase Predict Histologic Improvement in Pediatric Nonalcoholic Steatohepatitis

BACKGROUND AND AIMS

Predictive, noninvasive tools are needed to monitor key features of nonalcoholic fatty liver disease (NAFLD) in children that relate to improvement in liver histology. The purpose of this study was to evaluate the relationship between liver chemistries and liver histology using data from the CyNCh (Cysteamine Bitartrate Delayed-Release for the Treatment of NAFLD in Children) clinical trial.

APPROACH AND RESULTS

This study included 146 children. Improvement in liver histology, defined as decrease in nonalcoholic fatty liver disease (NAFLD) Activity Score ≥2 points without worsening of fibrosis, occurred in 43 participants (30%). There were 46 participants with borderline zone 1 nonalcoholic steatohepatitis (NASH) at baseline, with resolution in 28% (12 of 46). Multivariate models were constructed using baseline and change in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) at 52 weeks, for improvement in (1) liver histology primary outcome, (2) borderline zone 1 NASH, and (3) fibrosis. For improvement in histology, the model (P < 0.0001) retained baseline and change in GGT (area under the receiver operating characteristic [AUROC], 0.79; 95% confidence interval [CI], 0.71-0.87). For borderline zone 1 NASH, the model (P = 0.0004) retained baseline and change in ALT (AUROC, 0.80; 95% CI, 0.67-0.93). For fibrosis, the model (P < 0.001) retained baseline and change in ALT (AUROC, 0.80; 95% CI, 0.67-0.93). Additional clinical parameters were added to the models using Akaike's information criterion selection, and significantly boosted performance: improvement in histology with AUROC of 0.89 (95% CI, 0.82-0.95), borderline zone 1 NASH with AUROC of 0.91 (95% CI, 0.83-0.99), and fibrosis with AUROC of 0.89 (95% CI, 0.82-0.94). Models were validated using data from the TONIC (Treatment of Nonalcoholic Fatty Liver Disease in Children) trial.

CONCLUSIONS

In children with NAFLD, dynamic changes in serum ALT and GGT are associated with change in liver histology and appear to be powerful indicators of histological response.

Prenatal Exposure to Perfluoroalkyl Substances Associated With Increased Susceptibility to Liver Injury in Children

BACKGROUND AND AIMS

Per- and polyfluoroalkyl substances (PFAS) are widespread and persistent pollutants that have been shown to have hepatotoxic effects in animal models. However, human evidence is scarce. We evaluated how prenatal exposure to PFAS associates with established serum biomarkers of liver injury and alterations in serum metabolome in children.

APPROACH AND RESULTS

We used data from 1,105 mothers and their children (median age, 8.2 years; interquartile range, 6.6-9.1) from the European Human Early-Life Exposome cohort (consisting of six existing population-based birth cohorts in France, Greece, Lithuania, Norway, Spain, and the United Kingdom). We measured concentrations of perfluorooctane sulfonate, perfluorooctanoate, perfluorononanoate, perfluorohexane sulfonate, and perfluoroundecanoate in maternal blood. We assessed concentrations of alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyltransferase in child serum. Using Bayesian kernel machine regression, we found that higher exposure to PFAS during pregnancy was associated with higher liver enzyme levels in children. We also measured child serum metabolomics through a targeted assay and found significant perturbations in amino acid and glycerophospholipid metabolism associated with prenatal PFAS. A latent variable analysis identified a profile of children at high risk of liver injury (odds ratio, 1.56; 95% confidence interval, 1.21-1.92) that was characterized by high prenatal exposure to PFAS and increased serum levels of branched-chain amino acids (valine, leucine, and isoleucine), aromatic amino acids (tryptophan and phenylalanine), and glycerophospholipids (phosphatidylcholine [PC] aa C36:1 and Lyso-PC a C18:1).

CONCLUSIONS

Developmental exposure to PFAS can contribute to pediatric liver injury.

Progression of Fatty Liver Disease in Children Receiving Standard of Care Lifestyle Advice

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is the most common pediatric chronic liver disease. Little is known about outcomes in recognized youth.

METHODS

We compared paired liver biopsies from 122 of 139 children with NAFLD (74% male; 64% white; 71% Hispanic; mean age, 13 ± 3 years; age range, 8-17 years) who received placebo and standard of care lifestyle advice in 2 double-blind, randomized clinical trials within the nonalcoholic steatohepatitis (NASH) clinical research network from 2005 through 2015. We analyzed histologic changes with respect to baseline and longitudinal change in clinical variables using regression analysis.

RESULTS

At enrollment, 31% of the children had definite NASH, 34% had borderline zone 1 NASH, 13% had borderline zone 3 NASH, and 21% had fatty liver but not NASH. Over a mean period of 1.6 ± 0.4 years, borderline or definite NASH resolved in 29% of the children, whereas 18% of the children with fatty liver or borderline NASH developed definite NASH. Fibrosis improved in 34% of the children but worsened in 23%. Any progression to definite NASH and/or in fibrosis was associated with adolescent age, and higher waist circumference, levels of alanine or aspartate aminotransferase, total and low-density lipoprotein cholesterol at baseline (<0.05), and over follow-up time, with increasing level of alanine aminotransferase, hemoglobin A1C (P<.05), gamma-glutamyl transferase and development of type 2 diabetes (P<.01). Increasing level of gamma-glutamyl transferase was also associated with reduced odds of any improvement (P = .003).

CONCLUSIONS

One-third of children with NAFLD enrolled in placebo groups of clinical trials had histologic features of progression within 2 years, in association with increasing obesity and serum levels of aminotransferases and loss of glucose homeostasis.

Deep-learning-based accurate hepatic steatosis quantification for histological assessment of liver biopsies

Hepatic steatosis droplet quantification with histology biopsies has high clinical significance for risk stratification and management of patients with fatty liver diseases and in the decision to use donor livers for transplantation. However, pathology reviewing processes, when conducted manually, are subject to a high inter- and intra-reader variability, due to the overwhelmingly large number and significantly varying appearance of steatosis instances. This process is challenging as there is a large number of overlapped steatosis droplets with either missing or weak boundaries. In this study, we propose a deep-learning-based region-boundary integrated network for precise steatosis quantification with whole slide liver histopathology images. The proposed model consists of two sequential steps: a region extraction and a boundary prediction module for foreground regions and steatosis boundary prediction, followed by an integrated prediction map generation. Missing steatosis boundaries are next recovered from the predicted map and assembled from adjacent image patches to generate results for the whole slide histopathology image. The resulting steatosis measures both at the pixel level and steatosis object-level present strong correlation with pathologist annotations, radiology readouts and clinical data. In addition, the segregated steatosis object count is shown as a promising alternative measure to the traditional metrics at the pixel level. These results suggest a high potential of artificial intelligence-assisted technology to enhance liver disease decision support using whole slide images.

Perspectives on youth-onset nonalcoholic fatty liver disease

BACKGROUND

The prevalence and incidence of youth-onset nonalcoholic fatty liver disease (NAFLD) far exceeds other paediatric chronic liver diseases and represents a considerable public health issue globally.

METHODS

Here, we performed a narrative review of current knowledge regarding the epidemiology of paediatric NAFLD, selected concepts in pathogenesis, comorbidities, diagnosis, and management, and issues related to the transition to adulthood.

RESULTS

Paediatric NAFLD has become increasingly more prevalent, especially in certain subgroups, such as children with obesity and certain races/ethnicities. The pathophysiology of paediatric NAFLD is complex and multifactorial, driven by an interaction of environmental and genetic factors. Once developed, NAFLD in childhood is associated with type 2 diabetes, hypertension, increased cardiovascular disease risk, and end-stage liver disease. This predicts an increased burden of morbidity and mortality in adolescents and young adults. Early screening and diagnosis are therefore crucial, and the development of noninvasive biomarkers remains an active area of investigation. Currently, treatment strategies are focused on lifestyle changes, but there is also research interest in pharmacological and surgical options. In the transition from paediatric to adult care, there are several potential challenges/barriers to treatment and research is needed to understand how best to support patients during this time.

CONCLUSIONS

Our understanding of the epidemiology and pathophysiology of paediatric NAFLD has increased considerably over recent decades, but several critical knowledge gaps remain and must be addressed in order to better mitigate the short-term and long-term risks of youth-onset NAFLD.

Increased atherogenic lipoprotein profile in children with non-alcoholic steatohepatitis

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has been shown to be an independent risk factor for cardiovascular disease. In adults, histologic severity of non-alcoholic steatohepatitis (NASH) is associated with a more atherogenic profile.

OBJECTIVE

To assess cardiovascular disease risk by lipoprotein profile in children with NAFLD and compare to histologic assessment of severity.

METHODS

Nuclear magnetic resonance lipoprotein profile including lipoprotein particle sizes, apolipoproteins and the lipoprotein insulin resistance (LP-IR) index was measured in serum samples collected from 76 children at the time of a clinically indicated liver biopsy for NAFLD. Liver histology was scored using the NASH Clinical Research Network criteria and grouped into NASH or non-NASH.

RESULTS

Children with NASH had higher apolipoprotein B to apolipoprotein AI, ApoB/ApoAI (0.56 [IQR, 0.45-0.70] vs 0.66 [IQR, 0.56-0.79], P = .02) and higher LP-IR index (61 ± 21.9 vs 68 ± 17.3, P = .05) compared to children with non-NASH. Severity of hepatocyte ballooning was associated with higher ApoB/ApoAI ratios (P = .01), while high-density lipoprotein size was inversely associated with hepatic fat accumulation (P = .04).

CONCLUSION

While dyslipidaemia is common among children with NAFLD, this data suggests severity of the histologic features is closely associated with severity of cardiometabolic risk. Further studies are needed to understand the role of treatment of NASH in children to prevent future cardiometabolic disease.

Hepatic fat is a stronger correlate of key clinical and molecular abnormalities than visceral and abdominal subcutaneous fat in youth

INTRODUCTION

Body fat distribution is strongly associated with cardiometabolic disease (CMD), but the relative importance of hepatic fat as an underlying driver remains unclear. Here, we applied a systems biology approach to compare the clinical and molecular subnetworks that correlate with hepatic fat, visceral fat, and abdominal subcutaneous fat distribution.

RESEARCH DESIGN AND METHODS

This was a cross-sectional sub-study of 283 children/adolescents (7-19 years) from the Yale Pediatric NAFLD Cohort. Untargeted, high-resolution metabolomics (HRM) was performed on plasma and combined with existing clinical variables including hepatic and abdominal fat measured by MRI. Integrative network analysis was coupled with pathway enrichment analysis and multivariable linear regression (MLR) to examine which metabolites and clinical variables associated with each fat depot.

RESULTS

The data divided into four communities of correlated variables (|r|>0.15, p<0.05) after integrative network analysis. In the largest community, hepatic fat was associated with eight clinical biomarkers, including measures of insulin resistance and dyslipidemia, and 878 metabolite features that were enriched predominantly in amino acid (AA) and lipid pathways in pathway enrichment analysis (p<0.05). Key metabolites associated with hepatic fat included branched-chain AAs (valine and isoleucine/leucine), aromatic AAs (tyrosine and tryptophan), serine, glycine, alanine, and pyruvate, as well as several acylcarnitines and glycerophospholipids (all q<0.05 in MLR adjusted for covariates). The other communities detected in integrative network analysis consisted of abdominal visceral, superficial subcutaneous, and deep subcutaneous fats, but no clinical variables, fewer metabolite features (280, 312, and 74, respectively), and limited findings in pathway analysis.

CONCLUSIONS

These data-driven findings show a stronger association of hepatic fat with key CMD risk factors compared with abdominal fats. The molecular network identified using HRM that associated with hepatic fat provides insight into potential mechanisms underlying the hepatic fat-insulin resistance interface in youth.

Perfluoroalkyl substances and severity of nonalcoholic fatty liver in Children: An untargeted metabolomics approach

BACKGROUND

Toxicant-associated steatohepatitis has been described in adults but less is known regarding the role of toxicants in liver disease of children. Perfluoroalkyl substances (PFAS) cause hepatic steatosis in rodents, but few previous studies have examined PFAS effects on severity of liver injury in children.

OBJECTIVES

We aimed to examine the relationship of PFAS to histologic severity of nonalcoholic fatty liver disease (NAFLD) in children.

METHODS

Seventy-four children with physician-diagnosed NAFLD were recruited from Children's Healthcare of Atlanta between 2007 and 2015. Biopsy-based liver histological features were scored for steatosis, lobular and portal inflammation, ballooning, and fibrosis. Plasma concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonic acid (PFHxS), and untargeted plasma metabolomic profiling, were determined using liquid chromatography with high-resolution mass spectrometry. A metabolome-wide association study coupled with pathway enrichment analysis was performed to evaluate metabolic dysregulation associated with PFAS. A structural integrated analysis was applied to identify latent clusters of children with more severe form of NAFLD based on their PFAS levels and metabolite pattern.

RESULTS

Patients were 7-19 years old, mostly boys (71%), Hispanic (51%), and obese (85%). The odds of having nonalcoholic steatohepatitis (NASH), compared to children with steatosis alone, was significantly increased with each interquartile range (IQR) increase of PFOS (OR: 3.32, 95% CI: 1.40-7.87) and PFHxS (OR: 4.18, 95% CI: 1.64-10.7). Each IQR increase of PFHxS was associated with increased odds for liver fibrosis (OR: 4.44, 95% CI: 1.34-14.8), lobular inflammation (OR: 2.87, 95% CI: 1.12-7.31), and higher NAFLD activity score (β coefficient 0.46; 95% CI: 0.03, 0.89). A novel integrative analysis identified a cluster of children with NASH, characterized by increased PFAS levels and altered metabolite patterns including higher plasma levels of phosphoethanolamine, tyrosine, phenylalanine, aspartate and creatine, and decreased plasma levels of betaine.

CONCLUSIONS

Ηigher PFAS exposure was associated with more severe disease in children with NAFLD. PFAS may be an important toxicant contributing to NAFLD progression; however larger, longitudinal studies are warranted to confirm these findings.

Low Awareness of Nonalcoholic Fatty Liver Disease in a Population-Based Cohort Sample: the CARDIA Study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States, yet little is known about NAFLD awareness in individuals with incidental fatty liver on imaging.

OBJECTIVE

To assess the level of awareness of imaging-defined NAFLD among individuals with and without metabolic risk factors.

DESIGN

Cross-sectional analysis within a prospective longitudinal population-based cohort study conducted in four U.S. cities.

PARTICIPANTS

Adults age 43 to 55 years enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) Study who underwent computed tomography and a personal health questionnaire at the year 25 exam (2010-2011, n = 2788).

MAIN MEASURES

NAFLD was defined as liver attenuation ≤ 51 Hounsfield units after exclusion of other causes of liver fat. Participants were considered "NAFLD aware" if they reported being told previously by a doctor or nurse that they had "fatty liver."

KEY RESULTS

NAFLD prevalence was 23.9%. Only 16 of 667 (2.4%) participants with CT-defined NAFLD were aware of a NAFLD diagnosis. NAFLD aware participants were more likely to be white (81.3% vs. 53.5%, p = 0.03) and have the metabolic syndrome (87.5% vs. 59.3%, p = 0.02) and/or hypertension (75.0% vs. 50.2%, p = 0.05). In multivariable analyses adjusted for demographics, metabolic syndrome and hypertension remained predictive of NAFLD awareness.

CONCLUSION

There is low awareness of NAFLD among individuals with hepatic steatosis on imaging, even among those with metabolic risk factors. These findings highlight an opportunity to raise public and practitioner awareness of NAFLD with the goal of increasing diagnosis and implementing early treatment strategies.

Associations of Added Sugar from All Sources and Sugar-Sweetened Beverages with Regional Fat Deposition in US Adolescents: NHANES 1999-2006

BACKGROUND

The relative distribution of upper- versus lower-body fat may be an important determinant of cardiometabolic disease risk in youths. Dietary components associated with adolescent regional body fat distribution require further investigation.

OBJECTIVE

To evaluate associations of added sugar intake overall and from sugar-sweetened beverages (SSBs) with relative upper-body fat deposition in US adolescents.

METHODS

This was a cross-sectional analysis of data from 6585 adolescents (aged 12-19 y) in the NHANES cycles 1999-2006. Trunk, leg, and total fat mass were assessed by DXA. Participants were grouped into categories of total and SSB added sugar intake as a percentage of total energy intake (TEI) in 5% increments. Stepwise multivariable linear regression was used to examine associations of added sugar intake with truncal-to-leg fat ratio (TLR) and truncal-to-total fat ratio (TTR).

RESULTS

There were no associations of total added sugar intake with TLR or TTR. For SSB added sugar, compared with the lowest category of intake (<2% TEI), the highest category (>22% TEI) was associated with higher log-TLR [β (95% CI): >22% TEI versus <2% TEI: 0.05 (0.01, 0.09)] and TTR [1.30 (0.53, 2.07)] in the partially adjusted model with sex, age, race/ethnicity, income, physical activity, and smoking status as covariates (P-trend = 0.0001 for both). When BMI z-score and TEI were added as covariates, the magnitude of the associations were attenuated, but remained significant [log-TLR β (95% CI): 0.03 (0.005, 0.06), P-trend = 0.0018; TTR β (95% CI): 0.75 (0.27, 1.23), P-trend = 0.0004].

CONCLUSIONS

These findings support that added sugar from beverages is associated with higher upper-body adiposity, though the magnitude and clinical significance of the associations may be small, especially when adjusted for BMI and TEI. Additional studies are needed to elucidate the underlying biological mechanisms to explain these findings.

Plasma High-Resolution Metabolomics Differentiates Adults with Normal Weight Obesity from Lean Individuals

OBJECTIVE

This study explored underlying metabolism-related dysfunction by examining metabolomic profiles in adults categorized as lean, as having normal weight obesity (NWO), or as having overweight/obesity.

METHODS

Participants (N = 179) had fasting plasma analyzed by liquid chromatography and high-resolution mass spectrometry for high-resolution metabolomics. Body composition was assessed by dual-energy x-ray absorptiometry. NWO was defined as BMI < 25 and body fat > 30% for women and > 23% for men. Differentiating metabolomic features were determined by using linear regression models and likelihood ratio tests with false discovery rate correction. Mummichog was used for pathway and network analyses.

RESULTS

A total of 222 metabolites significantly differed between the groups at a false discovery rate of q = 0.2. Linoleic acid, β-alanine, histidine, and aspartate/asparagine metabolism pathways were significantly enriched (all P < 0.01) by metabolites that were similarly upregulated in the NWO and overweight/obesity groups compared with the lean group. A module analysis linked branched-chain amino acids and amino acid metabolites as elevated in the NWO and overweight/obesity groups compared with the lean group (all P < 0.05).

CONCLUSIONS

Metabolomic profiles of individuals with NWO reflected similar metabolic disruption as those of individuals with overweight/obesity. High-resolution metabolomics may help identify people at risk for developing obesity-related disease, despite normal BMI.

Segmentation of Overlapped Steatosis in Whole-Slide Liver Histopathology Microscopy Images

An accurate steatosis quantification with pathology tissue samples is of high clinical importance. However, such pathology measurement is manually made in most clinical practices, subject to severe reader variability due to large sampling bias and poor reproducibility. Although some computerized automated methods are developed to quantity the steatosis regions, they present limited analysis capacity for high resolution whole-slide microscopy images and accurate overlapped steatosis division. In this paper, we propose a method that extracts an individual whole tissue piece at high resolution with minimum background area by estimating tissue bounding box and rotation angle. This is followed by the segmentation and segregation of steatosis regions with high curvature point detection and an ellipse fitting quality assessment method. We validate our method with isolated and overlapped steatosis regions in liver tissue images of 11 patients. The experimental results suggest that our method is promising for enhanced support of steatosis quantization during the pathology review for liver disease treatment.

Sedentary Behaviors in Today's Youth: Approaches to the Prevention and Management of Childhood Obesity: A Scientific Statement From the American Heart Association

This scientific statement is about sedentary behavior and its relationship to obesity and other cardiometabolic outcomes in youth. A deleterious effect of sedentary behavior on cardiometabolic health is most notable for screen-based behaviors and adiposity; however, this relation is less apparent for other cardiometabolic outcomes or when sedentary time is measured with objective movement counters or position monitors. Increasing trends of screen time are concerning; the portability of screen-based devices and abundant access to unlimited programming and online content may be leading to new patterns of consumption that are exposing youth to multiple pathways harmful to cardiometabolic health. This American Heart Association scientific statement provides an updated perspective on sedentary behaviors specific to modern youth and their impact on cardiometabolic health and obesity. As we reflect on implications for practice, research, and policy, what emerges is the importance of understanding the context in which sedentary behaviors occur. There is also a need to capture the nature of sedentary behavior more accurately, both quantitatively and qualitatively, especially with respect to recreational screen-based devices. Further evidence is required to better inform public health interventions and to establish detailed quantitative guidelines on specific sedentary behaviors in youth. In the meantime, we suggest that televisions and other recreational screen-based devices be removed from bedrooms and absent during meal times. Daily device-free social interactions and outdoor play should be encouraged. In addition, parents/guardians should be supported to devise and enforce appropriate screen time regulations and to model healthy screen-based behaviors.

Development of a Plasma Screening Panel for Pediatric Nonalcoholic Fatty Liver Disease Using Metabolomics

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children, but diagnosis is challenging due to limited availability of noninvasive biomarkers. Machine learning applied to high-resolution metabolomics and clinical phenotype data offers a novel framework for developing a NAFLD screening panel in youth. Here, untargeted metabolomics by liquid chromatography-mass spectrometry was performed on plasma samples from a combined cross-sectional sample of children and adolescents ages 2-25 years old with NAFLD (n = 222) and without NAFLD (n = 337), confirmed by liver biopsy or magnetic resonance imaging. Anthropometrics, blood lipids, liver enzymes, and glucose and insulin metabolism were also assessed. A machine learning approach was applied to the metabolomics and clinical phenotype data sets, which were split into training and test sets, and included dimension reduction, feature selection, and classification model development. The selected metabolite features were the amino acids serine, leucine/isoleucine, and tryptophan; three putatively annotated compounds (dihydrothymine and two phospholipids); and two unknowns. The selected clinical phenotype variables were waist circumference, whole-body insulin sensitivity index (WBISI) based on the oral glucose tolerance test, and blood triglycerides. The highest performing classification model was random forest, which had an area under the receiver operating characteristic curve (AUROC) of 0.94, sensitivity of 73%, and specificity of 97% for detecting NAFLD cases. A second classification model was developed using the homeostasis model assessment of insulin resistance substituted for the WBISI. Similarly, the highest performing classification model was random forest, which had an AUROC of 0.92, sensitivity of 73%, and specificity of 94%. Conclusion: The identified screening panel consisting of both metabolomics and clinical features has promising potential for screening for NAFLD in youth. Further development of this panel and independent validation testing in other cohorts are warranted.