title: The combination of liver stiffness measurement and NAFLD fibrosis score improves the noninvasive diagnostic accuracy for severe liver fibrosis in patients with nonalcoholic fatty liver disease.
abstract: OBJECTIVE
  The accuracy of noninvasive tools for the diagnosis of severe fibrosis in patients with nonalcoholic fatty liver disease(NAFLD) in clinical practice is still limited. We aimed at assessing the diagnostic performance of combined noninvasive tools in two independent cohorts of Italian NAFLD patients.
  
  
  METHODS
  We analysed data from 321 Italian patients(179 Sicilian-training cohort, and 142 northern Italy-validation cohort) with an histological diagnosis of NAFLD. Severe fibrosis was defined as fibrosis ≥ F3 according to Kleiner classification. The APRI, AST/ALT, BARD, FIB-4, and NFS scores were calculated according to published algorithms. Liver stiffness measurement(LSM) was performed by FibroScan. Cut-off points of LSM, NFS and FIB-4 for rule-in or rule-out F3-F4 fibrosis were calculated by the reported formulas.
  
  
  RESULTS
  In the Sicilian cohort AUCs of LSM, NFS, FIB-4, LSM plus NFS, LSM plus FIB-4, and NFS plus FIB-4 were 0.857, 0.803, 0.790, 0.878, 0.888 and 0.807, respectively, while in the northern Italy cohort the corresponding AUCs were 0.848, 0.730, 0.703, 0.844, 0.850, and 0.733 respectively. In the training cohort, the combination of LSM plus NFS was the best performing strategy, providing false positive, false negative and uncertainty area rates of 0%,1.1% and 48% respectively. Similar results were obtained in the validation cohort with false positive, false negative and uncertainty area rates of 0%,7.3% and 40.8%.
  
  
  CONCLUSIONS
  The combination of LSM with NFS, two complementary, easy-to-perform, and widely available tools, is able to accurately diagnose or exclude the presence of severe liver fibrosis, also reducing of about 50-60% the number of needed diagnostic liver biopsies.
authors.affiliation: Sezione di Gastroenterologia, DiBiMIS, University of Palermo, Palermo, Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Petta
authors.forename: Ester
authors.initials: E
authors.lastname: Vanni
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Bugianesi
authors.forename: Vito
authors.initials: V
authors.lastname: Di Marco
authors.forename: Calogero
authors.initials: C
authors.lastname: Cammà
authors.forename: Daniela
authors.initials: D
authors.lastname: Cabibi
authors.forename: Lavinia
authors.initials: L
authors.lastname: Mezzabotta
authors.forename: Antonio
authors.initials: A
authors.lastname: Craxì
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D019540:Area Under Curve; D001219:Aspartate Aminotransferases / Q000097:blood; D001706:Biopsy; D005260:Female; D006801:Humans; D007558:Italy; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000473:pathology*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase
keywords: LSM; NAFLD; NFS