ORLANDO — Consider a diagnosis other than nonalcoholic fatty liver disease when an obese child or adolescent presents with elevated levels of the liver enzyme alanine aminotransferase.
Dr. Daniel Preud'Homme and colleagues reviewed the medical records of 372 children and adolescents who were referred for evaluation and management of obesity to the pediatric healthy life center at the University of South Alabama, Mobile. A complete metabolic profile for each patient included liver testing with serum ALT measurements. Mean age was 14 years; mean body mass index was 39 kg/m
Of the 113 patients with abnormally high ALT (greater than 48 U/L), 8 (7%) were diagnosed with a condition other than nonalcoholic fatty liver disease, said Dr. Preud'Homme, a pediatric gastroenterologist at the university.
The index case was a 13-year-old girl who had four abnormally high ALT assays over 2 years. The results were attributed to her obesity only, when in fact she had autoimmune hepatitis type 1, Dr. Preud'Homme said during a poster presentation at the annual meeting of the American College of Gastroenterology.
Two other patients with abnormally high ALT levels had smooth muscle antibody-positive and antinuclear antibody-positive assays consistent with autoimmune hepatitis type 1. This finding supports a need for a more comprehensive evaluation in any patient with elevated ALT levels, obese or not, Dr. Preud' Homme said. He recommended testing for all liver diseases, performing an ultrasound, and, in some cases, taking biopsies.
Two other patients had indeterminate biopsies, and Dr. Preud'Homme said he plans to closely follow these patients and repeat the biopsies. Another two originally assumed to have fatty liver disease were diagnosed with alpha-1 antitrypsin deficiency. One child was diagnosed with Wilson's disease, a rare, inherited condition in which a patient cannot fully metabolize copper.
“If we assume ALT is elevated because [of obesity], we are likely to miss other diseases. The percentage is high enough to warrant not ignoring it,” he said.