Concise Review: Fatty Liver in Pediatrics

A recent review (J Schwimmer. Hepatology 2016; 1718-25) provides a succinct up-to-date approach to the common problem of Nonalcoholic Fatty Liver Disease.

As this was a review, much of the material has been covered by this blog and previous publications.  The review discusses the upper limit of normal for alanine aminotransferase and its utility.  Liver imaging is discussed: “MRI is well suited for use in clinical research” whereas “ultrasound does not meet the standard clinical threshold required to be used to diagnose fatty liver…or used as an outcome measure.”

Dr. Schwimmer reviews a prospective study of 347 overweight or obese children with suspected NAFLD (blog review of this study: Screening for NAFLD).  He notes that 24% (n=61) of those who underwent liver biopsy ultimately had other diagnoses, especially autoimmune liver disease (n=11) and celiac disease (n=4). “The clinical challenge is to determine who needs how much of a workup. The greater potential for hepatotoxicity and the more advanced the disease is believed to be, the greater the need to be certain of the diagnosis and to properly grade and stage the disease.”  Currently, “no other diagnostic modality has shown sufficient accuracy to be appropriate for clinical use in the place of biopsy.”

He reviews associated health conditions with NAFLD including obesity, dyslipidemia, hypertension, cardiac dysfunction, and obstructive sleep apnea (~60% of NAFLD patients).

What about treatment? “There is not an available, proven, safe, and effective [pharmacologic] treatment for NAFLD in children…Current treatment is …focused on optimizing lifestyle, including nutrition, physical activity, and mental well-being.”

My take: Despite 20 years of clinical practice, the workup for NAFLD remains a vexing problem.  It is not practical to offer a liver biopsy to 10% of the pediatric population.  So determining who (besides those with more severe presentations) will benefit from an exhaustive workup remains unclear.  In the meanwhile, at a minimum, we need to keep looking for treatable liver conditions (eg. autoimmune hepatitis, celiac disease, Wilson’s disease, and viral hepatitis).

An article with a similar focus (Dr. Schwimmer is the corresponding author): J Pediatric 2016; 172: 9-13.  This report and Dr. Schwimmer’s review both tout the safety of liver biopsy.  Neither report presents much data on costs of either liver biopsies or MRI.

Related blog posts:

Zoo Atlanta 2016

Zoo Atlanta 2016