Accuracy of four commercially available serologic tests, including two office-based tests and a commercially available 13C urea breath test, for diagnosis of Helicobacter pylori.

BACKGROUND: Diagnosis of H. pylori infection may be made by endoscopic (invasive) tests, or by nonendoscopic (noninvasive) tests. Our aim was to evaluate recently available nonendoscopic tests, including two office-based serologic tests and a commercially available 13C urea breath test.
METHODS: Gastric biopsy specimens (for culture and stain) from 178 patients (mean age 46 +/- 13.3 years, 79 men and 99 women), none of whom had received anti-H. pylori therapy, were tested for H. pylori infection. These tests were compared against two commercial serum IgG antibody immunoassays (Biowhittaker's Pyloristat, and Quidel), 2 office-based serum qualitative IgG antibody tests (FlexSure HP, and QuickVue One-Step), the Meretek 13C urea breath test, and the CLOtest (a biopsy urease test).
RESULTS: The breath test (n = 147) had the best accuracy (96%) of the noninvasive tests studied. The serologic tests had similar accuracy to one another (84%-90%). The major drawback of the serologic tests was suboptimal specificity (75%-87%). Diagnosis of H. pylori based on the two office-based tests were not significantly different compared to the quantitative IgG antibody tests. The CLOtest had an accuracy of 97%.
CONCLUSIONS: The Meretek 13C urea breath test is an excellent test, but is considerably more expensive than serologic tests. The FlexSure HP and the QuickVue One-Step office-based qualitative IgG serologic antibody tests gave similar results to laboratory based quantitative antibody tests, and are acceptable for initial diagnosis of H. pylori infection. The advantages of the office-based tests are low cost, simplicity, and immediacy of results.