Under-reporting of Hepatic Steatosis in Children: A Missed Opportunity for Early Detection

Abstract

To determine the prevalence of underreporting of hepatic steatosis found incidentally on computed tomography (CT). Retrospective cross-sectional study including patients <18years of age who had undergone unenhanced abdominal CT for evaluation of nephrolithiasis. Hepatic and splenic attenuation were measured independently by 2 reviewers. Hepatic steatosis was defined using various previously established criteria (4 original criteria designed to detect moderate/severe steatosis and 3 secondary criteria designed to identify mild steatosis). Radiology reports and clinical notes were reviewed for documentation of steatosis. Serum alanine aminotransferase levels were collected. Kappa statistics were used to assess agreement between reviewers. A total of 584 patients were included. Agreement between reviewers' measurements for categorical classification of presence of steatosis was excellent (kappa statistic agreement >87%). The prevalence of hepatic steatosis ranged from 3% to 35%, depending on the criterion. Using absolute liver attenuation <48 Hounsfield units (most likely reflective of the truth, given alanine aminotransferase distribution and body mass index data), the prevalence was 7% (n=42). Steatosis was reported for only 12 of 42 (28%) of these patients and was documented in clinical notes in only 3 of those cases. Hepatic steatosis is underreported as an incidental finding of CT for nephrolithiasis. Given the prevalence and silent nature of nonalcoholic fatty liver disease, a high level of suspicion is needed, so as not to miss the opportunity to identify steatosis in childhood.