title: Validation of the lactose-[13C]ureide breath test for determination of orocecal transit time by scintigraphy.
abstract: The breath test using oral administration of a 13C-labeled substrate, lactose-ureide (LU), to measure orocecal transit time (OCTT) was validated against 99mTc-scintigraphy. Although LU is not absorbed in the human small intestine, colonic bacteria readily metabolize LU, producing 13C-labeled CO2. The time at which 13CO2 appears in breath corresponds to the OCTT.
  
  
  METHODS
  Twenty-two healthy volunteers ingested a meal labeled with 99mTc and 13C-LU. Scintigraphy was performed over 8 h at time intervals of 10 or 15 min. OCTT with scintigraphy was defined as the time at which at least 10% of the label had entered the colon. Breath samples were obtained every 10-15 min for 10 h and measured by isotope ratio mass spectrometry. OCTT was defined as the time of first significant increase above baseline. The results were compared using correlation and Altman-Bland statistics.
  
  
  RESULTS
  OCTT results from scintigraphy (mean OCTT = 283+/-53 min) and breath test (mean OCTT = 292+/-58 min) correlated well (r = 0.94). Altman-Bland statistics showed close agreement between scintigraphy and breath test. No significant difference between male and female subjects was observed.
  
  
  CONCLUSIONS
  The breath test using 13C-LU is a valid alternative to scintigraphy techniques for measuring OCTT.
authors.affiliation: Center for Gastrointestinal Research, KU Leuven, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Geypens
authors.forename: R
authors.initials: R
authors.lastname: Bennink
authors.forename: M
authors.initials: M
authors.lastname: Peeters
authors.forename: P
authors.initials: P
authors.lastname: Evenepoel
authors.forename: L
authors.initials: L
authors.lastname: Mortelmans
authors.forename: B
authors.initials: B
authors.lastname: Maes
authors.forename: Y
authors.initials: Y
authors.lastname: Ghoos
authors.forename: P
authors.initials: P
authors.lastname: Rutgeerts
mesh_terms: D000328:Adult; D001944:Breath Tests; D002432:Cecum / Q000502:physiology; D004064:Digestive System / Q000000981:diagnostic imaging; D005260:Female; D005772:Gastrointestinal Transit; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D009055:Mouth; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid