Qualitative and quantitative clinical evaluation of the laser-assisted ratio analyser for detection of Helicobacter pylori infection by (13)C-urea breath tests

Abstract

Objectives: Currently, the (13)C-urea breath test is the reference method for non-invasive diagnosis of Helicobacter pylori infection and therapy control. Therefore, new technologies have been developed to measure the ratio of (13)CO(2)/(12)CO(2) in breath. The laser-assisted ratio analyser (LARA) device is based on optogalvanic effects of the stimulated CO(2) molecules.

Design: In this study, the LARA system is prospectively compared to conventional isotope ratio mass spectrometry (IRMS) analysis of (13)C-urea breath tests.

Methods: The (13)C-urea breath test was used to screen 103 patients for H. pylori infection. Breath samples were analysed by LARA and IRMS techniques.

Results: Seven breath tests could not be analysed by the LARA system, one by IRMS. Out of the remaining 95 breath tests, 13 were positive for H. pylori infection (13.7%). In reference to IRMS analysis (with a cut-off of > 5 delta per thousand at 30 min), LARA produced one false positive and one false negative breath test result giving a sensitivity of 92.3% and a specificity of 98.8%. The mean difference in delta over baseline values between IRMS and LARA measurements was 2.02 delta per thousand +/- 5.48 delta per thousand.

Conclusion: LARA allows the reliable qualitative evaluation of 13C-urea breath tests, but the quantitative results differ from IRMS findings.