Comparison of invasive and noninvasive tests for detecting Helicobacter pylori infection in bleeding peptic ulcers

Background: Eradication of Helicobacter pylori infection has been shown to prevent recurrent bleeding from peptic ulcers. However, the detection rate for H pylori infection seems to be underestimated in this group of patients and has been scarcely investigated. Methods: Eighty patients with bleeding peptic ulcer were studied for eviden ce of H pylori infection. Seventy-seven of these patients were enrolled as having H pylori infection after any one of the following 3 tests were posit ive: culture, histologic study, or any 2 of rapid urease test (CLO test), c arbon 13-labeled urea breath test (UBT), and serologic examination. Fresh b lood or blood-containing material in the gastric antrum was noted by panend oscopy in 22 patients (group A). In the remaining 55 cases there was no blo od in the antrum (group B). Results: The sensitivities of the CLO test, bacterial culture, histologic s tudy,C-13-labeled UBT, and immunoglobulin G serologic test were 45.5%, 36.4 %, 77.2%, 95.4%, and 100% in group A, respectively, and 70.9%, 40.0%, 70.9% , 92.7%, and 96.4%, respectively, in group B. There was a statistically sig nificant difference between the sensitivities found for CLO test and C-13-l abeled UBT (p < 0.05). Of these 5 tests, only the sensitivity of the CLO te st showed a statistically significant difference between groups A and B (p < 0.05). A delayed positive CLO test result was recorded in 13 patients (3 in group A, 10 in group B). Conclusion: Noninvasive tests seemed to be more sensitive than invasive tes ts in detecting H pylori infection in patients with bleeding peptic ulcers. Blood in the antrum might reduce the sensitivity of the CLO test but have no effect on the other tests. The CLO test should be observed for more than 24 hours because of the possibility of a delayed positive result in some p atients with bleeding peptic ulcers.