Best Cut-Off Values for [14C]-Urea Breath Tests for Helicobacter pylori Detection

Background: The 'test and treat' strategy for Helicobacter pylori is recommended in dyspeptic patients under 55 years of age with no alarm symptoms. Reliable non-invasive tests are therefore needed. The aim of this study was to assess the pre- and post-treatment accuracy of a low dose (1 μCi [37kBq]), short collecting time [14C]-UBT (urea breath test) in diagnosing H pylori infection, examining different methods to analyse the best cut-off points. Methods: The study included 119 patients. Endoscopy and [ 14C]-UBT were performed in the pre- and post-treatment setting. [14C]-UBT results were expressed in three different ways: 1) the measured disintegrations per minute (dpm) at sample time, 2) the difference (D) in dpm between sample time and the dpm at T0, 3) the ratio of dpm at sample time to dpm at T0. Results: Seventy-six out of the 119 patients (63.9%; 95% CI: 54.9 to 71.9) were infected. Seventy-three (96%) patients completed the follow-up. The most accurate results in both pre- (sensitivity 95.9%; specificity 97.7%) and post-treatment (sensitivity 90.9%; specificity 100%) were obtained using the difference (D) in dpm between sample time at T0 and at T12.5. Conclusion: A low dose [ 14C]-UBT, with a short collecting time, is a reliable method to evaluate H. pylori infection in both the pre- and post-treatment setting.