title: Diagnostic challenges of nonalcoholic fatty liver disease (NAFLD) in children of normal weight.
abstract: BACKGROUND
  Nonalcoholic fatty liver disease (NAFLD) is generally regarded as affecting the overweight or obese. Though previously reported, the notion that NAFLD occurs in the presence of normal body weight (adult BMI<25) is unfamiliar in adults and problematic in children. Normal-body-weight NAFLD accounts for approximately 15% of all NAFLD and may be more prevalent with certain ethnicities.
  
  
  METHODS
  We describe a case of a child who appeared to have normal-body-weight NAFLD, on the basis of typical age of presentation, ultrasonographically evident hepatic steatosis and compatible liver histology, including a NAFLD activity score of 7, but was shown conclusively to have cystic fibrosis. Further we present a clinical strategy for diagnosis of childhood NAFLD, which would discriminate between this patient and actual normal-body-weight NAFLD children in our clinical practice.
  
  
  CONCLUSIONS
  NAFLD requires affirmative diagnostic criteria and should not be merely a diagnosis of exclusion.
authors: Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8.
authors: Jason Y K
authors: JY
authors: Yap
authors: Constance
authors: C
authors: O'Connor
authors: Diana R
authors: DR
authors: Mager
authors: Glenn
authors: G
authors: Taylor
authors: Eve A
authors: EA
authors: Roberts