The urea breath test (UBT) is one of the most important non-invasive methods for detecting Helicobacter pylori infection. The test exploits the hydrolysis of orally administered urea by the enzyme urease, which H pylori produces in large quantities. Urea is hydrolysed to ammonia and carbon dioxide, which diffuses into the blood and is excreted by the lungs. Isotopically labelled CO2can be detected in breath using various methods.
Labelling urea with 13C is becoming increasingly popular because this non-radioactive isotope is innocuous and can be safely used in children and women of childbearing age
13C is a non-radioactive isotope that can be used safely for repeated testing, which is frequently required in clinical practice, and for detecting H pylori infection in children and women of childbearing age. Furthermore, 13C-urea has been the most widely used substrate in methodological studies performed to validate this kind of diagnostic test. Another relevant advantage of using the stable isotope is that breath samples can be sent by post or courier to remote analysis centres, thus promoting the distribution of the test, which can even be performed at home if the patients are adequately selected and instructed.