title: Gastroscopic real-time 13C-urea breath test.
abstract: OBJECTIVE
  Biopsy-based Helicobacter urease testing (HUT) may constitute a hazard in patients with bleeding disorders, those receiving anticoagulant therapy, and those with communicable diseases. In addition, definitive test results may not immediately be available. The aim of this study was to investigate the feasibility of breath testing for H. pylori during gastroscopy (gastroscopic breath testing, GBT) in comparison with the standard HUT in a prospective, randomized, and controlled study.
  
  
  METHODS
  A total of 119 patients were randomly allocated to undergo H. pylori testing with either HUT (n = 61) or GBT (n = 58) with 75 mg of 13C-labeled urea by endoscopic instillation. Breath samples were continuously analyzed using molecular correlation spectroscopy, displaying real-time results. The procedure time and time until definitive test results were obtained (mean plus or minus standard deviation) were recorded.
  
  
  RESULTS
  H. pylori was detected in 10 of 49 patients (20.4 %) with HUT and in 16 of 53 (30.2 %) with GBT. Contraindications to biopsy prevented HUT in 12 of 61 patients. GBT results could not be obtained in one of the 58 patients due to respiratory disease and in four for technical reasons. Slightly less time was required to carry out HUT than GBT (121 +/- 30 s vs. 164 +/- 36 s; P < 0.001). Definitive test results were available within 14.0 +/- 2.2 min using GBT in comparison with 19.6 +/- 9.1 h for HUT ( P < 0.001). GBT prolonged the time spent by the patient in the endoscopy room by only 5.6 min in comparison with HUT (45.1 +/- 8.5 min vs. 39.5 +/- 10.3 min; P < 0.01).
  
  
  CONCLUSIONS
  GBT provides immediate, definitive results and allows H. pylori testing in patients in whom biopsies are contraindicated, with only minimal prolongation of the procedure time.
authors.affiliation: Division of Gastroenterology, Zurich University Hospital, Zurich, Switzerland. Heiko.Fruehauf@usz.ch
authors.forename: H
authors.initials: H
authors.lastname: Fruehauf
authors.forename: N C
authors.initials: NC
authors.lastname: Lindenmann
authors.forename: K
authors.initials: K
authors.lastname: Volkart
authors.forename: P
authors.initials: P
authors.lastname: Bauerfeind
authors.forename: M
authors.initials: M
authors.lastname: Fried
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001944:Breath Tests / Q000379:methods; D002245:Carbon Dioxide / Q000032:analysis*; D002247:Carbon Isotopes; D005240:Feasibility Studies; D005260:Female; D005773:Gastroscopy; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000201:enzymology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013270:Stomach / Q000382:microbiology; D013272:Stomach Diseases / Q000175:diagnosis* / Q000382:microbiology; D013997:Time Factors; D014508:Urea; D014510:Urease / Q000032:analysis
chemical_list: D002247:Carbon Isotopes; D002245:Carbon Dioxide; D014508:Urea; D014510:Urease