The 13C-urea breath test to detect Helicobacter pylori injection:: a validated simple methodology with 50 mg 13C-urea

Background: Several modifications of the C-13-urea breath test have been published. For reasons of cost efficiency and practicability, the urea dose and measurement duration should be reduced while still maintaining excellent diagnostic accuracy, Aims: To establish a validated simple protocol for the urea breath test with 50 mg C-13-urea and to compare this protocol with the conventional urea breath test with 100 mg C-13-urea. Methods: Conventional urea breath test with 100 mg C-13-urea was performed on 152 dyspeptic patients. Full-cream cow's milk was used as the test meal. Breath tests were repeated using 50 mg C-13-urea and the breath samples were collected at baseline and at 10 (protocol t(10)). 15 (protocol t(15)) and 30 min (protocol t(30)), Helicobacter pylori status was assessed by rapid urease test, histology and conventional urea breath test with 100 Mg C-13-urea. Results: With protocol t(15), the best combination of sensitivity (99.1%), specificity (97.3%) and accuracy (98.7%) was obtained with a cut-off of 2.5parts per thousand. There was an extremely high correlation coefficient between the three protocols and conventional C-13-urea breath test (all P<0.001). Conclusions: A urea breath test with 50 Mg C-13-urea using a simple test meal and a 15-min sampling interval with a low cut-off seems to be cost-effective and convenient. In a well-standardized laboratory, this modification is not associated with any loss of diagnostic accuracy.