Braden B, Caspary W F, Lembcke B
Medical Department II, Johann Wolfgang Goethe University Frankfurt/Main.
Z Gastroenterol. 1999 Jun;37(6):477-81.
13C-urea breath tests have become clinical routine for the diagnosis of Helicobacter pylori infection and other isotope breath tests have been invented e.g. for gastric emptying or quantitative liver function testing. Recently, isotope-selective nondispersive infrared spectrometers (NDIRS) have been developed for the analysis of the 13CO2/12CO2-enrichment in breath. In this study, we prospectively tested the validity of a newly developed NDIRS in comparison to isotope ratio mass spectrometry (IRMS).
142 patients with dyspeptic symptoms were tested for Helicobacter pylori infection using the 13C-urea breath test. The isotope ratio analysis of the breath samples was performed in duplicate both using IRMS and NDIRS.
The results of the baseline-corrected 13CO2-exhalation values between IRMS and NDIRS were in excellent agreement. The mean difference between both methods was 0.28 +/- 1.93 delta/1000. Evaluating the qualitative urea breath test results in reference to IRMS as the reference the NDIRS had a sensitivity of 97.8% and a specificity of 98.9%.
The isotope-selective nondispersive infrared spectroscopy is going to become a reliable, but low-cost and easy-to-operate alternative to expensive isotope ratio mass spectrometry in the analysis of 13C-breath tests.
13C尿素呼气试验已成为诊断幽门螺杆菌感染的临床常规检查，并且还发明了其他同位素呼气试验，例如用于胃排空或定量肝功能检测。最近，已开发出同位素选择性非分散红外光谱仪（NDIRS）用于分析呼出气体中13CO2/12CO2的富集情况。在本研究中，我们前瞻性地测试了一种新开发的NDIRS与同位素比率质谱法（IRMS）相比的有效性。
使用13C尿素呼气试验对142例有消化不良症状的患者进行幽门螺杆菌感染检测。呼气样本的同位素比率分析分别使用IRMS和NDIRS重复进行。
IRMS和NDIRS之间经基线校正的13CO2呼出值结果高度一致。两种方法之间的平均差异为0.28±1.93δ/1000。以IRMS作为参考评估定性尿素呼气试验结果时，NDIRS的灵敏度为97.8%，特异性为98.9%。
在13C呼气试验分析中，同位素选择性非分散红外光谱法将成为一种可靠、低成本且易于操作的方法，可替代昂贵的同位素比率质谱法。
