Original Article: Nonalcoholic Fatty Liver Disease: Common Questions and Answers on Diagnosis and Management

Issue Date: November 15, 2020

See additional reader comments at: https://www.aafp.org/afp/2020/1115/p603.html

To the Editor: We thank Dr. Westfall and colleagues for their comprehensive article about nonalcoholic fatty liver disease (NAFLD). The article focused on adults and did not discuss the prevalence of NAFLD in children and adolescents. A retrospective review of liver histology in 742 child autopsies performed from 1993 to 2003 identified an adjusted NAFLD prevalence of 9.6% in two- to 19-year-olds that was standardized for age, gender, race, and ethnicity, and the study found a prevalence ranging from 0.7% in toddlers and preschoolers to 38% in children who were obese.¹ In a more recent study of unexpected childhood deaths in New York City, NAFLD was found histologically in 4.5% of children.²

Obesity, race, and metabolic and genetic factors with comorbidities are associated with NAFLD in children younger than 18 years. Although the literature considers risk factors, biomarkers, and imaging tools to be helpful for diagnosis, opinions differ about the use of invasive diagnostic procedures. A liver biopsy provides a definite diagnosis and allows for the assessment of disease severity; however, concerns about the risks of liver biopsies in adults also apply to children.³

The North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) issued a clinical practice guideline for the diagnostic evaluation of suspected NAFLD.⁴ The American Academy of Pediatrics (AAP) endorsed the guideline and key recommendations⁵:

• Screen children nine to 11 years of age who have risk factors such as obesity using an alanine transaminase test.

• Rule out other medical conditions (e.g., Wilson's disease, hepatitis C) using additional tests.

• Consider liver biopsy to detect the presence of fat deposits.

• Recommend diet modifications (e.g., reduction of sugar-sweetened beverages) and increased physical activity.

The NASPGHAN and AAP guidelines, pediatric gastroenterologists, and referral centers for patients with NAFLD are valuable resources that can assist family physicians in the diagnosis and management of this complex disease in children.

In Reply: Thank you for raising awareness of NAFLD in children and adolescents. NAFLD in this population was considered outside the scope of our article; however, this topic warrants family physicians' attention. Your letter describes the prevalence of and risk factors for NAFLD in children and provides current expert consensus recommendations. Adults with the onset of NAFLD in childhood may be most at risk of complications; therefore, primary care clinicians should identify these patients to allow for early intervention.¹

The American Association for the Study of Liver Diseases does not recommend screening for NAFLD in children who are overweight or obese; however, they acknowledge the risk of NAFLD in children with metabolic syndrome, diabetes mellitus, and excess weight.¹ Several national organizations provide guidance for the evaluation of suspected NAFLD in children, including the NASPGHAN and AAP. The National Institute for Health and Care Excellence guidelines are based on expert opinion and recommend that clinicians offer liver ultrasonography to children and adolescents with type 2 diabetes who do not use alcohol.² If the results are normal, ultrasonography should be repeated every three years.^1,2

Interventions for NAFLD affecting both children and adults include intensive lifestyle modifications. Family physicians can apply their expertise in treating the whole patient (and family) in a compassionate, contextual, and comprehensive way to engage patients in behavior changes.