title: Endoscopic diagnosis of Helicobacter pylori infection by rapid urease test in bleeding peptic ulcers: a prospective case-control study.
abstract: OBJECTIVE
  To assess the efficacy of rapid urease test (RUT) in patients with bleeding ulcers, as well as the effects of visible blood in the stomach and short-term (<24 h) use of standard-dose proton pump inhibitor (PPI) on RUT sensitivity.
  
  
  BACKGROUND
  The sensitivity of RUT in the diagnosis of Helicobacter pylori in upper gastrointestinal bleeding has been reported with conflicting results.
  
  
  METHODS
  This was a prospective case-control study evaluating 324 consecutive patients with bleeding peptic ulcers (study group) and 164 with uncomplicated ulcers (control group). The presence of H. pylori infection was determined by both RUT and histology. Prevalence of H. pylori infection and the RUT sensitivity in diagnosing the bacteria between study and control groups were conducted.
  
  
  RESULTS
  The prevalence of H. pylori infection in those with bleeding ulcers was significantly lower than that of controls (53.7% vs. 65.2%, P=0.015). The false-negative rate of RUT in the study group was significantly greater than that of the control group (16.7% vs. 5.6%, P=0.006), whereas the sensitivity rates in the study group with or without gastric blood were significantly lower than those of the controls (79.6% vs. 94.4%, P=0.005; 84.8% vs. 94.4%, P=0.019). There was no significant difference in RUT sensitivity between study group with or without visible gastric blood (P=0.41). The RUT sensitivity rate was also not significantly different between those treated with PPI and those without in patients with bleeding ulcers (82.7% vs. 85.7%, P=0.67).
  
  
  CONCLUSIONS
  This study shows that the sensitivity of RUT in patients with bleeding ulcers is reduced. The presence of blood in the stomach and the short-term use of standard-dose PPI do not affect the RUT sensitivity in bleeding ulcers.
authors.affiliation: Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital, Taipei, Taiwan.
authors.forename: Jui-Hsiang
authors.initials: JH
authors.lastname: Tang
authors.forename: Nai-Jen
authors.initials: NJ
authors.lastname: Liu
authors.forename: Hao-Tsai
authors.initials: HT
authors.lastname: Cheng
authors.forename: Ching-Song
authors.initials: CS
authors.lastname: Lee
authors.forename: Yin-Yi
authors.initials: YY
authors.lastname: Chu
authors.forename: Kai-Feng
authors.initials: KF
authors.lastname: Sung
authors.forename: Cheng-Hui
authors.initials: CH
authors.lastname: Lin
authors.forename: Yung-Kuan
authors.initials: YK
authors.lastname: Tsou
authors.forename: Jau-Min
authors.initials: JM
authors.lastname: Lien
authors.forename: Chi-Liang
authors.initials: CL
authors.lastname: Cheng
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D010438:Peptic Ulcer Hemorrhage / Q000150:complications* / Q000175:diagnosis / Q000382:microbiology / Q000473:pathology; D054328:Proton Pump Inhibitors / Q000008:administration & dosage; D012680:Sensitivity and Specificity; D013997:Time Factors; D014510:Urease / Q000032:analysis*
chemical_list: D054328:Proton Pump Inhibitors; D014510:Urease