title: The 13C-caffeine breath test detects significant fibrosis in patients with nonalcoholic steatohepatitis.
abstract: BACKGROUND
  The C-caffeine breath test (CBT) is a noninvasive tool for the evaluation of the cytochrome P450 system, implicated in the development of nonalcoholic steatohepatitis.
  
  
  OBJECTIVE
  To apply the CBT to assess the extent of hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD).
  
  
  METHODS
  Twenty-six consecutive patients (mean age 56.1+/-6.85 y, 69.2% women) with NAFLD underwent the CBT, in addition to the clinical and laboratory evaluations and liver biopsy. Ten healthy individuals matched for age served as controls.
  
  
  RESULTS
  Mean delta over baseline values differed significantly between patients and controls (1.51+/-0.9 vs. 2.37+/-0.8 Delta per thousand/mg, respectively) (P=0.01) and were significantly higher in patients with fibrosis stage <2 (Brunt's system) (2.0+/-0.77 vs. 1.3+/-0.9 for stage > or =2, P=0.05). Mean delta over baseline values correlated highly with fibrosis stage (P=0.01), albumin (P=0.007), international normalized ratio (P=0.04), bilirubin (P=0.0008), and platelet count (P=0.0001). On multivariate stepwise logistic regression analysis, CBT was the best predictor of severe fibrosis (stage > or =2) (odds ratio 0.274, 95% confidence interval 0.086-0.872, P=0.028), with an area under the curve of 0.788.
  
  
  CONCLUSIONS
  The CBT is safe and easy to perform. It can reliably predict severe hepatic fibrosis in patients with NAFLD. Further large-scale studies are still needed.
authors.affiliation: Liver Institute and Department of Medicine D, Beilinson Campus Rabin Medical Center, Petah Tiqwa, Israel.
authors.forename: Hemda
authors.initials: H
authors.lastname: Schmilovitz-Weiss
authors.forename: Yaron
authors.initials: Y
authors.lastname: Niv
authors.forename: Orit
authors.initials: O
authors.lastname: Pappo
authors.forename: Marisa
authors.initials: M
authors.lastname: Halpern
authors.forename: Jacklin
authors.initials: J
authors.lastname: Sulkes
authors.forename: Marius
authors.initials: M
authors.lastname: Braun
authors.forename: Nir
authors.initials: N
authors.lastname: Barak
authors.forename: Yaron
authors.initials: Y
authors.lastname: Rotman
authors.forename: Maya
authors.initials: M
authors.lastname: Cohen
authors.forename: Amal
authors.initials: A
authors.lastname: Waked
authors.forename: Ran
authors.initials: R
authors.lastname: Tur-Kaspa
authors.forename: Ziv
authors.initials: Z
authors.lastname: Ben-Ari
mesh_terms: D001944:Breath Tests / Q000379:methods*; D002110:Caffeine / Q000032:analysis*; D002247:Carbon Isotopes; D003937:Diagnosis, Differential; D005234:Fatty Liver / Q000150:complications* / Q000175:diagnosis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008103:Liver Cirrhosis / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D002247:Carbon Isotopes; D002110:Caffeine