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

Background. Diagnosis of H. pylori infection may be made by endoscopic (inv asive) tests, or by nonendoscopic (noninvasive) tests. Our aim was to evalu ate recently available nonendoscopic tests, including two office-based sero logic tests and a commercially available C-13 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 receiv ed anti-H. pylori therapy, were tested for H. pylori infection. These tests were compared against two commercial sei rum IgG antibody immunoassays (Bi owhittaker's Pyloristat, and Quidel), 2 office-based serum qualitative Ige antibody tests (FlexSure HP, and QuickVue One-Step), the Meretek C-13 urea breath test, and the CLOtest (a biopsy urease test). Results. The breath test (n = 147) had the best accuracy (96%) of the nonin vasive tests studied. The serologic tests had similar accuracy to one anoth er (84%-90%). The major drawback of the serologic tests was suboptimal spec ificity (75%-87%). Diagnosis of H. pylori based on the two office-based tes ts were not significantly different compared to the quantitative IgG antibo dy tests. The CLOtest had an accuracy of 97%. Conclusions. The Meretek C-13 urea breath test is an excellent test, but is considerably more expensive than serologic tests;The FlexSure HP and the Q uickVue One-Step office-based qualitative IgG serologic antibody tests gave similar results to laboratory based quantitative antibody tests, and are a cceptable for initial diagnosis of H. pylori infection. The advantages of t he office-based tests are low cost, simplicity, and immediacy of results.