title: Role of 13C-urea breath test in experimental model of Helicobacter pylori infection in mice.
abstract: BACKGROUND
  Animal models have been widely used to study Helicobacter pylori infection. Evaluation of H. pylori infection status following experimental inoculation of mice usually requires euthanasia. The (13) C-urea breath test ((13) C-UBT) is both sensitive and specific for detection of H. pylori in humans. Thus, it would be very useful to have such a test with the same accuracy for the follow-up of this infection in animal models of gastric infection. Accordingly, the purpose of this study was to develop and evaluate a (13) C-UBT method for following the course of H. pylori infection in a mouse model.
  
  
  METHODS
  A total of 50 female C57BL/6 mice were gavaged three times with either 10(8) colony-forming units of H. pylori (n=29) or saline solution only (n=21). After 2 months of infection, mice were fasted for 14 hours and (13) C-UBT was performed using 300 μg of (13) C-urea. The mice were killed, and the stomach was removed and processed for immunohistochemistry and PCR.
  
  
  RESULTS
  The optimal time for breath sample collection in mice was found to be 15 minutes. The (13) C-UBT cutoff was set at 3.0‰ δPDB. Using PCR as the gold standard, the sensitivity of (13) C-UBT and immunohistochemistry was 96.6 and 72.4%, respectively, while the specificity was 85.7 and 95.2%, respectively.
  
  
  CONCLUSIONS
  (13) C-UBT was shown to be a reliable method for the detection of H. pylori infection in C57BL/6 mice and was even more accurate than immunohistochemistry. The use of (13) C-UBT in the mouse model of H. pylori infection can be very useful to detect the bacterium without the need to kill the animals in long-term time course studies.
authors.affiliation: CEDOC, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal. antonio.santos@hsmarta.min-saude.pt
authors.forename: António Mário
authors.initials: AM
authors.lastname: Santos
authors.forename: Teresa
authors.initials: T
authors.lastname: Lopes
authors.forename: Mónica
authors.initials: M
authors.lastname: Oleastro
authors.forename: Paula
authors.initials: P
authors.lastname: Chaves
authors.forename: Rita
authors.initials: R
authors.lastname: Cordeiro
authors.forename: Maria
authors.initials: M
authors.lastname: Ferreira
authors.forename: Teresa
authors.initials: T
authors.lastname: Pereira
authors.forename: Jorge
authors.initials: J
authors.lastname: Machado
authors.forename: António Sousa
authors.initials: AS
authors.lastname: Guerreiro
mesh_terms: D000818:Animals; D001944:Breath Tests / Q000379:methods*; D004195:Disease Models, Animal; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000378:metabolism*; D007150:Immunohistochemistry; D007553:Isotope Labeling / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D016133:Polymerase Chain Reaction; D012376:Rodent Diseases / Q000175:diagnosis / Q000382:microbiology; D012680:Sensitivity and Specificity; D013270:Stomach / Q000382:microbiology; D014508:Urea / Q000378:metabolism*
chemical_list: D014508:Urea