title: Accuracy of urea breath test performed immediately after emergency endoscopy in peptic ulcer bleeding.
abstract: OBJECTIVE
  The aim of this work is to investigate the accuracy of the urea breath test (UBT) performed immediately after emergency endoscopy in peptic ulcer bleeding (PUB).
  
  
  METHODS
  Urea breath test was carried out right after emergency endoscopy in patients with PUB. The accuracy of this early UBT was compared to a delayed one after hospital discharge that was considered the gold standard. Clinical and epidemiological factors were analyzed in order to study their influence on the accuracy of the early UBT.
  
  
  RESULTS
  Early UBT was collected without any complication and good acceptance from all the 74 patients included. In 53 of the patients (71.6%), a delayed UBT was obtained. Comparing concordance between the two tests we have calculated an accuracy of 83% for the early UBT. Sensibility and specificity were 86.36 and 66%, respectively, with a positive predictive value of 92.68% and negative predictive value of 50% (Kappa index = 0.468; p = 0.0005; CI: 95%). We found no influence of epidemiological factors, clinical presentation, drugs, times to gastroscopy, Forrest classification, endoscopic therapy, hemoglobin, and urea levels over the accuracy of early UBT.
  
  
  CONCLUSIONS
  Urea breath test carried out right after emergency endoscopy in PUB is an effective, safe, and easy-to-perform procedure. The accuracy of the test is not modified by clinical or epidemiological factors, ulcer stage, or by the type of therapy applied. However, we have found a low negative predictive value for early UBT, so a delayed test is mandatory for all negative cases.
authors.affiliation: Department of Gastroenterology, Hospital Clínico de Valladolid, Valladolid, Spain. benitovelayos@hotmail.com
authors.forename: Benito
authors.initials: B
authors.lastname: Velayos
authors.forename: Luis
authors.initials: L
authors.lastname: Fernández-Salazar
authors.forename: Fernando
authors.initials: F
authors.lastname: Pons-Renedo
authors.forename: María F
authors.initials: MF
authors.lastname: Muñoz
authors.forename: Ana
authors.initials: A
authors.lastname: Almaraz
authors.forename: Rocío
authors.initials: R
authors.lastname: Aller
authors.forename: Lourdes
authors.initials: L
authors.lastname: Ruíz
authors.forename: Lourdes
authors.initials: L
authors.lastname: Del Olmo
authors.forename: Javier P
authors.initials: JP
authors.lastname: Gisbert
authors.forename: José M
authors.initials: JM
authors.lastname: González-Hernández
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001944:Breath Tests / Q000379:methods*; D004636:Emergency Service, Hospital; D016099:Endoscopy, Gastrointestinal; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000209:etiology / Q000601:surgery*; D041981:Gastrointestinal Tract / Q000382:microbiology; D016481:Helicobacter Infections / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000209:etiology / Q000601:surgery*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D014508:Urea / Q000378:metabolism*
chemical_list: D014508:Urea