title: Development and validation of a new histological score for pediatric non-alcoholic fatty liver disease.
abstract: OBJECTIVE
  Pediatric non-alcoholic fatty liver disease (NAFLD) may present with a distinct histopathological pattern characterized by the presence of predominant portal-based injury and portal inflammation (PI). We aimed at developing a new grading score for pediatric NAFLD to be used in clinical trials that takes into account the presence of PI and the weight of histological features.
  
  
  METHODS
  Our training set consisted of 203 children with biopsy-proven NAFLD. The diagnosis of non-alcoholic steatohepatitis (NASH) was based on Brunt's criteria. Histological features were scored: steatosis (0-3), lobular inflammation (0-3), ballooning (0-2), and PI (0-2). Logistic regression analysis was performed to apply weight to each feature. The new score was called the Pediatric NAFLD Histological Score or PNHS. The validation set consisted of 100 children with NAFLD.
  
  
  RESULTS
  The mean age of the initial cohort was 12.4 ± 3.4 years and significant fibrosis (fibrosis stage ≥ 2) was present in 26 patients (12.8%). NASH was diagnosed in 135 patients with a mean NAS of 4.5 ± 1.4. The mean PNHS in the NASH group was 89 ± 20.5 compared to 21.9 ± 24.5 in the "not NASH" group, p<0.001. PNHS correlated with the presence of NASH according to the pathologist's diagnosis, better than the NAFLD activity score (NAS), p=0.011. The area under the ROC curve (AUC) for the diagnosis of NASH was 0.96 for PNHS. Similar findings were observed in the validation set with an AUC of 0.94.
  
  
  CONCLUSIONS
  PNHS may be used for histological grading of pediatric NAFLD with excellent correlation with the presence of NASH.
authors.affiliation: Department of Pediatric Gastroenterology, Cleveland Clinic, Cleveland, OH 44195, United States. alkhoun@ccf.org
authors.forename: Naim
authors.initials: N
authors.lastname: Alkhouri
authors.forename: Rita
authors.initials: R
authors.lastname: De Vito
authors.forename: Anna
authors.initials: A
authors.lastname: Alisi
authors.forename: Lisa
authors.initials: L
authors.lastname: Yerian
authors.forename: Rocio
authors.initials: R
authors.lastname: Lopez
authors.forename: Ariel E
authors.initials: AE
authors.lastname: Feldstein
authors.forename: Valerio
authors.initials: V
authors.lastname: Nobili
mesh_terms: D000293:Adolescent; D002648:Child; D005234:Fatty Liver / Q000473:pathology*; D005260:Female; D006801:Humans; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000473:pathology; D008297:Male; D065626:Non-alcoholic Fatty Liver Disease