Di Silvio M, Larisch J, Dibildox M, Almaguer I, Gitler R, Dehesa M, Ramírez-Barba E J
Centro Médico Nacional 20 de Noviembre, Universidad Anáhuac, Escuela de Medicina.
Rev Gastroenterol Mex. 1998 Jul-Sep;63(3):135-42.
There are several diagnostic methods for Helicobacter pylori infection, some of them need an endoscopic procedure and biopsy to be performed (invasive) like the rapid urease test, culture and histology. Recently non invasive, specific, sensible, easy to perform and patient's well accepted methods had been developed known as breath test, based on the hydrolysis of labelled urea by Helicobacter pylori urease enzyme, to release ammonia and bicarbonate. Labelled CO2 reaches the bloodstream and the lungs, from where can be collected into the breath for quantification. Labelled urea has to options: 13C stable, non-radioactive and 14C unstable, radioactive. Breath test with 13C is based on the atomic mass difference between 12C and 13C and it is necessary a mass spectrometer and 40 minutes to perform it. Breath test with 14C has 1 uCi (one micro-curie) of radioactivity (1/300 of total radiation received in one year from the environment); the test takes 10 minutes and the samples are read in a beta counter. Both non-invasive tests had demonstrated sensitivity and specificity comparable to established "gold standards" for Helicobacter pylori infection diagnosis.
幽门螺杆菌感染有多种诊断方法，其中一些需要进行内镜检查和活检（侵入性方法），如快速尿素酶试验、培养和组织学检查。最近，基于幽门螺杆菌脲酶对标记尿素的水解作用以释放氨和碳酸氢盐而开发出了非侵入性、特异性强、灵敏度高、易于操作且患者易于接受的方法，即呼气试验。标记的二氧化碳进入血液循环和肺部，可从呼出气体中收集用于定量分析。标记尿素有两种选择：13C稳定、无放射性的和14C不稳定、有放射性的。13C呼气试验基于12C和13C之间的原子质量差异，需要一台质谱仪，检测过程需40分钟。14C呼气试验有1微居里（1/300的年环境辐射总量）的放射性；检测需10分钟，样本在β计数器中读取。这两种非侵入性检测方法的灵敏度和特异性均已证明与公认的幽门螺杆菌感染诊断“金标准”相当。
