The expense of the 13C-urea breath test (UBT) to detect Helicobacter pylori infection is mainly due to the cost of 13C-urea and the analysis using isotope ratio mass spectrometry (IRMS).
To test whether a UBT, using a lower dose of urea and lower-priced isotope-selective nondispersive infrared spectrometry (INIS), can preserve diagnostic efficacy in clinical practice.
A total of 177 dyspeptic patients received endoscopy for H. pylori culture and histology. All of them received a UBT in which the duplicate baseline, 10 min, and 15 min breath samples after ingestion of 50 mg 13C-urea were collected to analyse the excess 13CO2/12CO2 ratio (ECR) by IRMS (ABCA, Europa Scientific, UK) and INIS (UBiT-IR200, Photal Otsuka Electronics, Japan), respectively.
Of the 177 patients, 84 were infected and 93 were uninfected with H. pylori. A close correlation of ECR was found between IRMS and INIS (r=0.9829 at 10 min; r=0.9918 at 15 min, P < 0.0001). Analysing the 15-min samples, UBT by both IRMS and INIS achieved the same sensitivity (96.4%) and specificity (98.9%).
INIS is as effective as IRMS for UBT, and can use a lower dose of 13C-urea. This can provide an economic UBT, using the lower-priced INIS and a low dose of 13C-urea.