North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition have issued updated guidelines for the screening, diagnosis, and treatment of nonalcoholic fatty liver disease in children in response to an increase in the prevalence of this condition.
Eleven pediatricians and gastroenterologists analyzed 161 papers on NAFLD and nonalcoholic steatohepatitis in children and made 27 recommendations for healthcare providers. The recommendations were printed in the Journal of Pediatric Gastroenterology and Nutrition (2017;64:319-334).
The panel's head, Dr. Miriam Vos, an assistant professor of pediatrics and the research director of the Strong4Life Clinic at Children's Healthcare of Atlanta, remarked on the high caliber of recent studies. Dr. Vos commented, "It's a busy and exciting time for NAFLD." I was particularly struck by the abundance of high-quality studies addressing NAFLD. There's a common misconception that because NAFLD is a relatively new disease, there's little known about it.
Although about 10% of American children are thought to be affected, no treatments have yet been approved by the Food and Drug Administration (FDA).
Obese children (those with a body mass index in the 95th percentile or greater) and overweight children (those with a body mass index between the 85th and 94th percentiles) with risk factors such as central adiposity, insulin resistance, prediabetes or diabetes, or a family history of NAFLD or NASH should be screened for NAFLD between the ages of 9 and 11.
Due to their lack of symptoms, children can be challenged to screen for NAFLD, so screening is typically performed through blood-liver biochemistry or abdominal imaging. Clinical practitioners should not automatically diagnose NAFLD in a child who is either overweight or underweight and whose liver enzymes are persistently elevated.
The committee decided that the best available screening test is the measurement of alanine aminotransferase because it is widely known and requires very little patient cooperation. The normal range for ALT should be interpreted differently for the sexes, with an upper limit of 22 U/L for girls and 26 U/L for boys. They argue against using routine ultrasonography as the only screening method for fatty liver disease because of its low specificity and sensitivity.
Children at higher risk include overweight boys and children of color (white, Asian, and Hispanic). Although they acknowledged the lack of solid evidence, the panel argued against the previous recommendation against screening the siblings and parents of children with NAFLD who have known risk factors like obesity, Hispanic ethnicity, insulin resistance, prediabetes, diabetes, and dyslipidemia. Fasting serum glucose or hemoglobin A1c levels should be measured annually to check for diabetes in children with NAFLD, and screening should also occur at the time of diagnosis.
A definitive test for NAFLD has yet to be developed, so the panelists stressed the importance of ruling out other hepatic conditions that can cause elevated liver enzyme levels. However, the panelists acknowledged that missing another liver disease requiring alternate treatment could have significant and severe consequences, so the approach was still considered worthwhile. In children at high risk for developing NASH or advanced fibrosis, NAFLD should be evaluated with a liver biopsy rather than CT or ultrasonography.
Patients with new or ongoing risk factors, such as type 2 diabetes or NASH, may require repeat liver biopsies every two to three years after the initial biopsy to assess disease progression, particularly fibrosis. Due to a lack of outcome data in adolescents, the panel voted against bariatric surgery as a specific therapy for NAFLD.
Transforming one's way of life is the cornerstone of care for nonalcoholic fatty liver disease. The panelists suggest cutting down on sugary drinks, upping the amount of moderate- to vigorous-intensity exercise, and reducing the amount of time spent in front of screens to less than two hours per day.
The guidelines state that "all children with NAFLD should be offered lifestyle intervention counseling" if they are overweight or obese. The benefits of lifestyle counseling for overweight children may extend to those with nonalcoholic fatty liver disease or nonalcoholic steatohepatitis (NAFLD or NASH) because of the correlation between these factors and improved weight management outcomes in these children.
The panelists also created a chart outlining an algorithm that can be used to provide a plan of action in clinical scenarios. Dr. Vos remarked that the need for precise instructions for the clinical workup was a significant factor in the development of the algorithm. We arrived at this number partly because we know it's challenging to keep track of the number of kids diagnosed with NAFLD and decide when it's necessary to repeat tests, make referrals, or ramp up treatment. That's the kind of thing people ask me.
According to Joel Lavine, MD, professor of pediatrics and chief of gastroenterology, hepatology, and nutrition at Columbia University Medical Center in New York City, there has yet to be a consensus on how to diagnose or treat NAFLD.
Dr. Lavine argued that the guidelines needed more evidence, specifically longitudinal follow-up, for children. This topic was highlighted as a top research priority by the panel, alongside the identification of risk factors that indicate disease progression over regression, the development of noninvasive methods for detecting NAFLD and NASH, the creation of cost-effective strategies for screening, and the conduct of well-designed clinical trials to determine optimal treatment and medications.
Dr. Lavine, who contributed to the 2012 NAFLD clinical guidelines for the American Association for the Study of Liver Diseases, the American College of Gastroenterology, and the American Gastroenterological Association (Hepatology 2012;55:2005-2023), suggests that researchers interested in testing new interventions with patients who have just begun making recommended lifestyle changes wait about six months before testing.
—Helina Selemon