Alternative Etiologies of Liver Disease in Children With Suspected NAFLD

Prevalence and significance of autoantibodies in children with metabolic dysfunction-associated steatotic liver disease: A systematic review and meta-analysis

Significance of autoantibodies in pediatric metabolic dysfunction-associated steatotic liver disease (MASLD) is unknown. Our aim was to determine the prevalence and significance of autoantibodies in MASLD. PubMed and Scopus were searched and six articles (689 [487 males] MASLD patients) were identified. Antinuclear antibodies (ANA) was positive in 28% (95% confidence interval [CI]: 17%-39%, n = 6 studies), Antismooth muscle antibodies (ASMA) in 28% (95% CI: 8%-50%, n = 5 studies), Actin-positive in 15% (95% CI: 10%-20%, n = 2 studies) and elevated immunoglobulin G in 17% (95% CI: 1%-39%, n = 4 studies). Anti-liver-kidney-microsomal antibody was not present in any patient. There was no significant association of ANA positivity with degree of liver steatosis, liver fibrosis or nonalcoholic fatty liver disease activity score (NAS) but patients with ASMA positivity had advanced fibrosis (pooled risk ratio [RR] 1.77; 95% CI 1.16-2.71) and higher risk of NAS ≥5 (pooled RR 1.21; 95% CI: 1.01-1.44, n = 2 studies, 243 patients). To conclude, non-organ specific autoantibodies are present in over one-fourth of children with MASLD and the presence of ASMA maybe associated with increased disease severity.

The effects of weight loss interventions on children and adolescents with non-alcoholic fatty liver disease: A systematic review and meta-analysis

Background

Overall, there is conflicting evidence regarding the beneficial effects of optimal lifestyle modification, particularly weight loss interventions, with nonalcoholic fatty liver disease (non-alcoholic fatty liver disease (NAFLD)). Therefore, this study investigated the effects of weight loss interventions on laboratory and clinical parameters in children and adolescents with NAFLD.

Methods

Original databases (PubMed/MEDLINE, Web of Science, SCOPUS, and Embase) were searched using standard keywords to identify all controlled trials investigating the effects of weight loss interventions among NAFLD children and adolescents. Pooled weighted mean difference and 95% confidence intervals were achieved by random-effects model analysis.

Results

Eighteen eligible clinical trials were included in this systematic review and meta-analysis. The pooled findings showed that especially more intense weight loss interventions significantly reduced the glucose (p = 0.007), insulin (p = 0.002), homeostatic model assessment-insulin resistance (HOMA-IR) (p = 0.003), weight (p = 0.025), body mass index (BMI) (p = 0.003), BMI z-score (p < 0.001), waist circumference (WC) (p = 0.013), triglyceride (TG) (p = 0.001), and aspartate transaminase (AST) (p = 0.027). However, no significant changes were found in total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), alanine transaminase (ALT), and hepatic steatosis grades (all p > 0.05) following weight loss interventions.

Conclusions

Weight loss interventions had significant effects on NAFLD-related parameters including glucose, insulin, HOMA-IR, weight, BMI, BMI z-score, WC, TG, and AST.

Distinguishing Autoimmune Hepatitis From Steatohepatitis in Adolescents With Obesity and Positive Screening Alanine Aminotransferase

Screening children with obesity for nonalcoholic fatty liver disease leads to identification of elevated alanine aminotransferase (ALT) and is a common cause for referral to pediatric gastroenterology. Guidelines recommend that children with positive screening ALT be evaluated for causes of ALT elevation beyond nonalcoholic fatty liver disease. One clinical challenge is that autoantibodies can be present in patients with obesity and thus may or may not represent autoimmune hepatitis. This case series highlights the importance of a comprehensive evaluation to reach an accurate diagnosis.

Nonalcoholic Fatty Liver Disease in Young Children with Obesity

Background: To evaluate the prevalence of suspected nonalcoholic fatty liver disease (NAFLD) in young children with obesity and determine associated risk factors. Methods: Retrospective single-center study of children with obesity, ages 2-6 years. Suspected NAFLD was defined as an alanine aminotransferase (ALT) >30 U/L. Multivariable analyses were performed to determine predictors of elevated ALT. Results: Among 237 children 2-6 years old, 35% had elevated ALT. Multivariable analysis showed that higher BMI z score [odds ratio (OR): 1.5 confidence interval (95% CI: 1.04-1.92)] and higher gamma-glutamyl transferase (GGT) [OR: 21.3 (95% CI: 3.7-121.1)] predicted elevated ALT. Of those with ≥2 ALT levels, 38% (n = 33/86) had a persistently elevated ALT (median ALT >30 U/L). Only 7% of patients with ALT >30 U/L underwent further testing to evaluate for alternative causes of liver disease. Conclusion: Suspected NAFLD is common in young children with obesity and predicted by obesity severity and GGT. Other cardiometabolic markers were equivalent between those with normal vs. elevated ALT, suggesting NAFLD onset may precede development of comorbidities. Earlier screening will enable prompt diagnosis and intervention, which may prevent or delay the onset of cardiometabolic diseases commonly associated with NAFLD in adolescence and adulthood.

Comparison of MAFLD and NAFLD Characteristics in Children

Background & aims: An international panel proposed a diagnostic framework for metabolic-associated fatty liver disease (MAFLD) in children. The aim was to compare the clinical features of MAFLD and nonalcoholic fatty liver disease (NAFLD) in children. Methods: The characteristic differences between NAFLD and MAFLD in children were compared with the National Health and Nutrition Examination Survey (NHANES) 2017–2018 in the U.S. and the Comprehensive Prevention Project for Overweight and Obese Adolescents (CPOOA) study in China. Results: In NHANES 2017–2018, regardless of which criteria were implemented, participants with hepatic steatosis were more likely to have higher BMI z-scores, a higher prevalence of hypertension or higher metabolic indices and higher non-invasive liver fibrosis scores (all p < 0.05). The cases diagnosed by those two definitions had a similarity of over 75%. More obese children were diagnosed with MAFLD than NAFLD (p < 0.001). However, approximately 19% of children with NAFLD present with normal weight and fasting glucose levels and cannot be diagnosed with MAFLD. The CPOOA study excluded viral infected liver disease and certain kinds of congenital causes of liver steatosis patients, resulting in children with NAFLD being identical with MAFLD children. Conclusions: Most clinical features were similar between children with MAFLD and children with NAFLD, and more than 75% of children with NAFLD can also be diagnosed with MAFLD. However, approximately 19% of children with NAFLD cannot be categorized as MAFLD. Therefore, to gain greater benefits from renaming NAFLD to MAFLD in pediatrics, the prevalence of different causes of hepatic steatosis in children needs to be understood.

MAFLD and Celiac Disease in Children

Celiac disease (CD) is an immune-mediated systemic disorder elicited by the ingestion of gluten whose clinical presentation ranges from the asymptomatic form to clinical patterns characterized by multiple systemic involvement. Although CD is a disease more frequently diagnosed in patients with symptoms of malabsorption such as diarrhea, steatorrhea, weight loss, or failure to thrive, the raised rate of overweight and obesity among general pediatric and adult populations has increased the possibility to diagnose celiac disease in obese patients as well. Consequently, it is not difficult to also find obesity-related disorders in patients with CD, including "metabolic associated fatty liver disease" (MAFLD). The exact mechanisms linking these two conditions are not yet known. The going assumption is that a gluten-free diet (GFD) plays a pivotal role in determining an altered metabolic profile because of the elevated content of sugars, proteins, saturated fats, and complex carbohydrates, and the higher glycemic index of gluten-free products than gluten-contained foods, predisposing individuals to the development of insulin resistance. However, recent evidence supports the hypothesis that alterations in one of the components of the so-called "gut-liver axis" might contribute to the increased afflux of toxic substances to the liver triggering the liver fat accumulation and to the subsequent hepatocellular damage. The aim of this paper was to describe the actual knowledge about the factors implicated in the pathogenesis of hepatic steatosis in pediatric patients with CD. The presented review allows us to conclude that the serological evaluations for CD with anti-transglutaminase antibodies, should be a part of the general workup in the asymptomatic patients with "non-alcoholic fatty liver disease" (NAFLD) when metabolic risk factors are not evident, and in the patients with steatohepatitis when other causes of liver disease are excluded.

Evaluation of the feasibility of screening for paediatric non-alcoholic fatty liver disease

AIM

To evaluate the feasibility of screening for non-alcoholic fatty liver disease (NAFLD) in clinical practice and the acceptance of a screening strategy, and to identify factors that determine compliance.

METHODS

A screening protocol, based on alanine aminotransferase measurement and introduced to healthcare workers of Dutch outpatient obesity clinics in 2017, was evaluated. Medical files of children who visited the largest outpatient obesity clinic between 2017 and 2020 were evaluated. Focus group discussions (FGDs) were conducted with 14 healthcare workers who had been using the screening protocol.

RESULTS

Screening for NAFLD was performed in 477/571 (84%) of the children. Loss of follow-up was the major reason for inadequate screening. Follow-up was performed in 81/134 children with an abnormal screening result (61%). The FGDs indicated 13 barriers for screening, regarding guideline- and knowledge-related issues.

CONCLUSION

Screening for NAFLD was performed in the vast majority of the children. However, adherence to the guideline after an abnormal initial screening result needs to be improved. This can be achieved by improving the loss of follow-up of patients' and physicians' awareness of the relevance of mildly elevated ALT levels.

Intensive Lifestyle Management Improves Steatosis and Fibrosis in Pediatric Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Childhood obesity, with associated comorbidities such as nonalcoholic fatty liver disease (NAFLD), is an increasing global health problem. Although lifestyle management is the mainstay of treatment, its efficacy on liver fibrosis has not yet been established.

METHODS

Children and adolescents admitted for severe obesity at a tertiary center (Zeepreventorium, De Haan, Belgium) were enrolled in this prospective study. Intensive lifestyle therapy encompassed caloric restriction, physical activity, education on a healthy lifestyle, and psychosocial support. At baseline, 6 months, and 12 months, liver ultrasound and transient elastography with controlled attenuation parameter were performed to assess liver steatosis and fibrosis.

RESULTS

A total of 204 patients (median age, 14.0 y; body mass index Z-score, +2.8) were evaluated at admission. NAFLD on ultrasound was present in 71.1%, whereas 68.6% had controlled attenuation parameter values of 248 dB/m or greater. A total of 32.8% of patients had at least F2 fibrosis, including 10.3% with transient elastography of 9 kPa or greater. After 6 months, the median body weight loss was 16.0% in the 167 patients evaluated. Fibrosis improved in 75.0% (P < .001). Baseline severity of liver fibrosis and steatosis were predictors of fibrosis resolution. Seventy-nine patients had reached the 1-year time point. The improvements were sustained because fibrosis regressed at least 1 stage in all patients with baseline fibrosis. Fasting serum alanine aminotransferase and homeostasis model assessment of insulin resistance decreased significantly over the 1-year period (P < .001).

CONCLUSIONS

NAFLD and associated fibrosis are highly prevalent in children and adolescents with severe obesity. An intensive multidisciplinary lifestyle management program that causes significant weight loss not only improves liver steatosis, but also fibrosis.

Autoimmune Antibodies in Children and Adolescents With Nonalcoholic Fatty Liver Disease

OBJECTIVES

The clinical significance of autoantibody positivity in nonalcoholic fatty liver disease (NAFLD) in the absence of autoimmune hepatitis (AIH) remains uncertain. We aimed to determine the prevalence of autoantibodies in a pediatric cohort with biopsy-proven NAFLD and investigate the association between autoantibodies and NAFLD histologic grade.

METHODS

Single-center, retrospective study of patients ≤21 years with biopsy-proven NAFLD from 2014 to 2019. Clinical and laboratory data were obtained within 90 days of liver biopsy. Autoantibody positivity was defined as serum titer ≥1:80 or units ≥20. Liver biopsies were evaluated for features of AIH, then scored for steatosis, hepatocyte ballooning, lobular inflammation, and NAFLD activity score (NAS) was calculated. Portal inflammation and fibrosis were scored separately. Multivariable logistic regression was used for continuous and binary outcomes.

RESULTS

Sixty-seven subjects met inclusion criteria. Positive antinuclear antibody (ANA), antismooth muscle antibody (ASMA), antineutrophil cytoplasmic antibody (ANCA), anti-F-actin antibody (F-actin), anti-liver kidney microsomal (LKM) antibody, or any combination was observed in 43%, 39%, 19%, 13%, 0%, and 66% of subjects, respectively. After controlling for confounders, positive ANA and alanine aminotransferase (ALT) >80 had 4.6 greater odds of having an NAS ≥5 ( P = 0.035; 95% confidence interval [CI], 1.12-19.01). Autoantibody positivity resolution occurred in 10%-50% who underwent serial monitoring.

CONCLUSIONS

Autoantibodies, except LKM, were frequently encountered in our pediatric NAFLD cohort in the absence of AIH. ANA positivity with ALT may help clinically stratify pediatric patients with suspected NAFLD targeting those at greater risk for nonalcoholic steatohepatitis (NASH).

Nonalcoholic Steatohepatitis in Children

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in children. Although environmental factors are major contributors to early onset, children have both shared and unique genetic risk alleles as compared with adults with NAFLD. Treatment relies on reducing environmental risk factors, but many children have persistent diseases. No medications are approved specifically for the treatment of NAFLD, but some anti-obesity or diabetes treatments may be beneficial. Pediatric NAFLD increases the risk of diabetes and other cardiovascular risk factors. Long-term prospective studies are needed to determine the long-term risk of hepatic and non-hepatic morbidity and mortality in adulthood.

Meta-analysis: global prevalence, trend and forecasting of non-alcoholic fatty liver disease in children and adolescents, 2000-2021

BACKGROUND

NAFLD is increasing in children.

AIMS

To determine the recent trend and forecast the future global prevalence of paediatric NAFLD METHODS: We searched PubMed, Embase, Web of Science and Cochrane library databases from inception to 1 May 2021 for studies of children and adolescents (≤21 years) with NAFLD. Obesity was defined with weight at ≥95th percentile and overweight as 85th to <95th percentile as per the Center for Disease Control BMI-for-age percentile cut-offs.

RESULTS

From 3350 titles and abstracts, we included 74 studies (276,091 participants) from 20 countries/regions. We included 14 studies in the general NAFLD prevalence analysis, yielding an overall prevalence of 7.40% (95% CI: 4.17-12.81) regardless of the diagnostic method, and 8.77% (95% CI: 3.86-18.72) by ultrasound. Among continents with more than one study, the prevalence of NAFLD was 8.53% (95% CI: 5.71-12.55) for North America, 7.01% (95% CI: 3.51-13.53) for Asia, and 1.65% (95% CI: 0.97-2.80) for Europe. NAFLD prevalence regardless of the diagnostic method was 52.49% (95% CI: 46.23-58.68, 9159 participants) and 39.17% (95% CI: 30.65-48.42, 5371 participants) among obese and overweight/obese participants, respectively. For the general population, trend analysis from 2000 to 2017 indicates an increasing global prevalence of paediatric NAFLD from 4.62% to 9.02% at a yearly increase of 0.26%, whereas forecast analysis predicts a prevalence of 30.7% by 2040.

CONCLUSION

The prevalence of paediatric NAFLD varies by region and is 52.49% overall among the obese population and 7.40% in the general population. It is predicted to reach 30.7% by 2040.

Metabolic-associated fatty liver disease from childhood to adulthood: State of art and future directions

In 2020, an international group of experts proposed to replace the term of nonalcoholic fatty liver disease with metabolic-associated fatty liver disease (MAFLD). This recent proposal reflects the close association of fatty liver with metabolic derangements, as demonstrated by previous robust data. Several factors [including genetics, inflammation, metabolic abnormalities, insulin resistance (IR), obesity, prenatal determinants, and gut–liver axis] have been found to be involved in MAFLD pathophysiology, but this tangled puzzle remains to be clearly understood. In particular, IR has been recognized as a key player in metabolic impairments development in children with fatty liver. On this ground, MAFLD definition focuses on the pathophysiological basis of the disease, by emphasizing the crucial role of metabolic impairments in this condition. Although primarily developed for adults, MAFLD diagnostic criteria have been recently updated with an age-appropriate definition for sex and age percentiles, because of the increasing attention to cardiometabolic risk in childhood. To date, accumulating evidence is available on the feasibility of MAFLD definition in clinical practice, but some data are still conflicting in highly selected populations. Considering the growing prevalence worldwide of fatty liver and its close relationship with metabolic dysfunction both in children and adults with subsequent increased cardiovascular risk, early strategies for MAFLD identification, treatment and prevention are needed. Novel therapeutic insights for MAFLD based on promising innovative biological techniques are also emerging. We aimed to summarize the most recent evidence in this intriguing research area both in children and adults.

Evaluation of Hepatitis in Pediatric Patients With Presumed Nonalcoholic Fatty Liver Disease

In 2017, the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition published clinical practice guidelines for the assessment and diagnosis of nonalcoholic fatty liver disease (NAFLD). We determined how frequently these investigations suggest an alternate etiology for chronic hepatitis in 8- to 17-year-old patients with body mass index >85%, elevated alanine aminotransferase and radiographic steatosis, and rates of adherence to 2017 guidelines.

Methods

We conducted a retrospective chart review of patients presenting to McMaster Children's Hospital from 2017-2020 for evaluation of suspected NAFLD. Bloodwork was reviewed.

Results

Ninety-five patients met inclusion criteria. Abnormal bloodwork that required further testing was found in 28.4%; a different chronic liver disease was ultimately diagnosed in 11.6%. Only 9.5% received comprehensive, additional bloodwork for other causes of liver disease.

Conclusion

A high proportion of patients evaluated for suspected NAFLD had bloodwork possibly suggesting an alternate diagnosis. Comprehensive testing was infrequently performed. These results reinforce the importance of maintaining a differential diagnosis among children presumed to have NAFLD.

American Association of Clinical Endocrinology Clinical Practice Guideline for the Diagnosis and Management of Nonalcoholic Fatty Liver Disease in Primary Care and Endocrinology Clinical Settings: Co-Sponsored by the American Association for the Study of Liver Diseases (AASLD)

OBJECTIVE

To provide evidence-based recommendations regarding the diagnosis and management of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) to endocrinologists, primary care clinicians, health care professionals, and other stakeholders.

METHODS

The American Association of Clinical Endocrinology conducted literature searches for relevant articles published from January 1, 2010, to November 15, 2021. A task force of medical experts developed evidence-based guideline recommendations based on a review of clinical evidence, expertise, and informal consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.

RECOMMENDATION SUMMARY

This guideline includes 34 evidence-based clinical practice recommendations for the diagnosis and management of persons with NAFLD and/or NASH and contains 385 citations that inform the evidence base.

CONCLUSION

NAFLD is a major public health problem that will only worsen in the future, as it is closely linked to the epidemics of obesity and type 2 diabetes mellitus. Given this link, endocrinologists and primary care physicians are in an ideal position to identify persons at risk on to prevent the development of cirrhosis and comorbidities. While no U.S. Food and Drug Administration-approved medications to treat NAFLD are currently available, management can include lifestyle changes that promote an energy deficit leading to weight loss; consideration of weight loss medications, particularly glucagon-like peptide-1 receptor agonists; and bariatric surgery, for persons who have obesity, as well as some diabetes medications, such as pioglitazone and glucagon-like peptide-1 receptor agonists, for those with type 2 diabetes mellitus and NASH. Management should also promote cardiometabolic health and reduce the increased cardiovascular risk associated with this complex disease.

Non-Invasive Approaches to Estimate Liver Steatosis and Stiffness in Children With Non-Alcoholic Fatty Liver Disease

OBJECTIVES

To develop pediatric-specific models that predict liver stiffness and hepatic steatosis in non-alcoholic fatty liver disease (NAFLD), based on clinical and laboratory data.

METHODS

Children with NAFLD, who had undergone magnetic resonance imaging with proton density fat fraction (MRI-PDFF) for steatosis quantification and/or magnetic resonance elastography (MRE) for liver stiffness assessment were included. We used data from patients imaged between April 2009 to July 2018 to develop a predictive model for fat fraction and stiffness. We validated the performance of the models using data from a second cohort, imaged between 2018 and 2019.

RESULTS

The first cohort (n = 344) consisted of predominantly non-Hispanic (80%), male (67%) adolescents. MRE data were available for 343 children, while PDFF data were available for 130. In multivariable regression, ethnicity, insulin levels, platelet count, and aspartate aminotransferase independently predicted liver stiffness and these variables were used to develop the predictive model. Similarly, sex, ethnicity, alanine aminotransferase, and triglycerides levels independently predicted liver PDFF and were used in the PDFF model. The AUC of the optimal cutoff for the model that predicted a stiffness of >2.71 kPa was 0.70 and for the model that predicted PDFF >5% was 0.78. The validation group (n = 110) had similar characteristics. The correlation coefficient of the model with the measured liver stiffness was 0.30 and with the measured liver PDFF was 0.26.

CONCLUSIONS

Pediatric-specific models perform poorly at predicting exact liver stiffness and steatosis; however, in the absence of magnetic resonance imaging can be used to predict the presence of significant steatosis (>5%) and/or significant stiffness (>2.71). Thus, imaging remains an invaluable adjunct to laboratory investigations in determining disease severity.

Case report: A case of severe acute hepatitis of unknown origin

According to analyses of etiology, clinical features, diagnostic methods, and treatment strategies by summarizing a case of unexplained acute hepatitis recently experienced, we are aiming to provide some information to enrich the clinical experience in diagnosis and treatment of severe acute hepatitis of unknown etiology in young children. A boy, aged 10 years and 6 months old, was admitted to the hospital due to acute abdominal pain, jaundice, and exceptionally high levels of ALT and AST. A range of measures, including patient history, physical examination, and routine laboratory testing, were performed. Furthermore, strategies such as trio-based next-generation sequencing (Trio-NGS) and liver biopsy, as well as metagenomic NGS (mNGS) of blood and liver samples were also performed. In summary, this case was an acute severe non-A-E hepatitis that is a probable case with hepatitis of unknown origin. Immunohistochemical analysis showed an immune injury in liver tissues. Torque teno virus (TTV) sequences were detected by mNGS assay. As for treatment strategies, in addition to general treatment, this patient also underwent plasmapheresis and methylprednisolone treatment due to disease deterioration. The patient's liver function was improved afterward and discharged after one month of treatment. Taken together, this work reported the clinical feature and treatment of severe acute hepatitis with non-A-E hepatitis in detail. The potential mechanism of liver damage might be due to an immune attack in which TTV might play a role as a co-factor.

Nonalcoholic Fatty Liver Disease in Children

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. It represents a spectrum of disease from simple hepatic steatosis to steatohepatitis that may develop into progressive hepatic fibrosis and even cirrhosis. NAFLD is the most rapidly increasing indication for liver transplantation in adults. In children, the incidence of NAFLD has also increased over the past decade. Although the majority of children with NAFLD are overweight or obese, there is an increasing subset of children with normal body mass index with so-called lean NAFLD. NAFLD in children is associated with several extrahepatic manifestations, including hyperlipidemia, insulin resistance, and obstructive sleep apnea. The pathogenesis of NAFLD in children involves a multifactorial interaction among genetics, in utero exposures, early childhood exposures, and ongoing nutritional exposures. Although there are some similarities between pediatric NAFLD and adult NAFLD, liver biopsies in children show histologic differences between the two. The current standard-of-care treatment of NAFLD in children is lifestyle change to decrease caloric intake and increase physical activity. There are no medications currently approved for the treatment of NAFLD in children. This article aims to summarize the current understanding of pediatric NAFLD and future directions for intervention and therapeutic aims.