title: 13C-methacetin and 13C-galactose breath tests can assess restricted liver function even in early stages of primary biliary cirrhosis.
abstract: OBJECTIVE
  The 13C-methacetin breath test quantitatively evaluates cytochrome P450-dependent liver function. The 13C-galactose breath test non-invasively measures the galactose oxidation capacity of the liver. The aim of this study was to find out whether these breath tests are sensitive parameters also in non-cirrhotic patients with primary biliary cirrhosis.
  
  
  METHODS
  Nineteen patients with early-stage primary biliary cirrhosis (no cirrhotic alterations in the liver biopsy, Ludwig stage I-III) and 20 healthy controls underwent the 13C-methacetin and 13C-galactose breath tests.
  
  
  RESULTS
  Patients with primary biliary cirrhosis metabolized less 13C-methacetin than controls (cumulative recovery within 30 min 7.5+/-2.4% versus 14.0+/-2.6%; p < 0.001). When a cut-off > 9.8% was used for the cumulative recovery after 30 min, the methacetin breath test reached 84.2% sensitivity and 95.0 specificity. In the 13C-galactose breath test, the percentage recovery at 60 min in patients was 3.1+/-1.3%/h, and 6.3+/-1.1%/h in controls (p < 0.001). Using a cut-off > 4.7%/h, the galactose breath test reached 89.5% sensitivity and 95.0 specificity.
  
  
  CONCLUSIONS
  In non-cirrhotic, early-stage, primary biliary cirrhosis the 13C-methacetin breath test and the 13C-galactose breath test reliably indicate decreased liver function. The 13C-galactose breath test can also predict the histological score.
authors.affiliation: Medical Department I, Johann Wolfgang Goethe University of Frankfurt/Main, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Holtmeier
authors.forename: Maria
authors.initials: M
authors.lastname: Leuschner
authors.forename: Arne
authors.initials: A
authors.lastname: Schneider
authors.forename: Ulrich
authors.initials: U
authors.lastname: Leuschner
authors.forename: Wolfgang F
authors.initials: WF
authors.lastname: Caspary
authors.forename: Barbara
authors.initials: B
authors.lastname: Braden
mesh_terms: D000081:Acetamides; D000328:Adult; D000368:Aged; D000465:Algorithms; D001944:Breath Tests / Q000379:methods*; D016022:Case-Control Studies; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005260:Female; D005690:Galactose; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008105:Liver Cirrhosis, Biliary / Q000175:diagnosis* / Q000378:metabolism; D008111:Liver Function Tests / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
chemical_list: D000081:Acetamides; C035495:methacetin; D003577:Cytochrome P-450 Enzyme System; D005690:Galactose