Helicobacter pylori infection rates in duodenal ulcer patients in the United States may be lower than previously estimated.

OBJECTIVE: Published studies have estimated the rate of Helicobacter pylori (H. pylori) infection in patients with duodenal ulcer disease to be as high as 95%; the majority of remaining duodenal ulcers have been attributed to the use of ulcerogenic drugs such as nonsteroidal antiinflammatory drugs (NSAIDs). We aimed to assess the H. pylori prevalence rates of U.S. duodenal ulcer patients in large, well-controlled studies.

METHODS: More than 2900 patients with endoscopically diagnosed non-NSAID duodenal ulcers were enrolled in a series of six placebo-controlled, double-blind studies conducted in the United States that assessed H. pylori using a combination of tests. Patients were considered infected with H. pylori only if culture growth was observed, or both histological and CLOtest results were positive. Patients were considered uninfected if the results of at least two tests were negative. Patients with missing test results, results of only a single test, or conflicting test results were not evaluable for H. pylori assessment.

RESULTS: Of the 2394 endoscopically diagnosed evaluable duodenal ulcer patients, 73% (1737) were confirmed infected with H. pylori at study entry.

CONCLUSIONS: The results of six carefully designed and controlled studies suggest that an assumed H. pylori infection rate of approximately 95% may overestimate the actual rate of H. pylori infection in duodenal ulcer patients in the United States. Although H. pylori infection is an important factor in the etiology of noniatrogenic duodenal ulcer disease, other factors may predominate in some patients and should not be overlooked in determining an appropriate course of treatment. The empiric use of antibiotic therapy for ulcer patients without confirmation of the presence of H. pylori cannot be recommended.