H. pylori antibody test, urea breath test
This test is used to diagnose bacterial infections that cause stomach ulcers.
Helicobacter pylori are bacteria that are very common in the general population and the most frequent cause of stomach ulcers. The test for detecting these bacteria in the breath is based on their ability to convert urea, which is produced naturally by the body, into carbon dioxide (CO2), which the human body cannot make itself. The test therefore consists of administering urea containing carbon-13 (13C), an isotope (type) of non-radioactive carbon present in very small quantities in the air, and then measuring the increase in the levels of this rare carbon in the form of CO2 in the exhaled breath. If there is no H. pylori infection, urea will not be converted, and the carbon-13 level in the breath will be the same as that in the air. If the bacteria are present, the exhaled air will contain a higher level of carbon-13 than the air. A positive breath test confirms the presence of active bacteria in the stomach and justifies a treatment (or repeat treatment) with antibiotics. It is essential that patients adhere to the pre-testing requirements concerning antibiotic or other medication restrictions.