title: Rapid urease tests lack sensitivity in Helicobacter pylori diagnosis when peptic ulcer disease presents with bleeding.
abstract: OBJECTIVE
  The eradication of Helicobacter pylori (H. pylori) in patients with bleeding peptic ulcer disease (PUD) decreases the rate of ulcer rebleeding. Although all methods for H. pylori diagnosis have been extensively evaluated in uncomplicated PUD the efficacy of the commonly used rapid urease test (RUT) has not been established in patients with bleeding peptic ulcer disease. The aim of this study was to evaluate the efficacy of the RUT (CLOtest) in patients with bleeding duodenal ulcers (DUs).
  
  
  METHODS
  Consecutive patients with symptoms of upper GI tract hemorrhage and a DU at the time of endoscopy were evaluated. The presence of H. pylori infection was determined by RUT, microbiology, and histology. Consecutive patients with uncomplicated DUs were similarly evaluated. The prevalence of H. pylori as determined by the RUT alone was compared to that determined by a combination of all tests in both patient groups.
  
  
  RESULTS
  Fifty-five patients with bleeding DUs and 69 with nonbleeding DUs were evaluated. The prevalence of H. pylori in patients presenting with bleeding was 72.7% (95% confidence interval [CI] 61.0-84.5%) and lower than the prevalence rate of 92.8% (95% CI 86.6-98.8%) in patients with uncomplicated PUD (p < 0.05). The prevalence of H. pylori in the bleeding DU group as determined by RUT alone (54.5%) was less than that determined by a combination of all tests (73%) with a false-negative rate of 10 of 40 (25%; 95% CI 11.6-38.4%) (p < 0.05). This false-negative rate was significantly greater than that observed in the group presenting with dyspepsia (1 of 64 [1.6%; 95% CI 0-4.6%]) (p < 0.01).
  
  
  CONCLUSIONS
  The prevalence of H. pylori is lower in patients with bleeding DUs when compared to patients with uncomplicated DUs. In addition, the sensitivity and negative predictive value of the RUT is lower in patients presenting with bleeding, and other methods of H. pylori diagnosis should be used in this patient group.
authors.affiliation: Department of Gastroenterology, Meath Hospital, Trinity College, Dublin, Ireland.
authors.forename: J M
authors.initials: JM
authors.lastname: Lee
authors.forename: N P
authors.initials: NP
authors.lastname: Breslin
authors.forename: C
authors.initials: C
authors.lastname: Fallon
authors.forename: C A
authors.initials: CA
authors.lastname: O'Morain
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D005260:Female; D005753:Gastric Mucosa / Q000737:chemistry / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000201:enzymology / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D010438:Peptic Ulcer Hemorrhage / Q000150:complications*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014510:Urease / Q000032:analysis*
chemical_list: D014510:Urease