What is urease breath test?

The urease breath test is a diagnostic test used to detect the presence of Helicobacter pylori (H. pylori), a type of bacteria that commonly infects the stomach and causes gastritis and gastric ulcers. The test involves the ingestion of a urea solution containing a non-radioactive isotope of carbon (usually carbon-13 or carbon-14) and the subsequent measurement of the carbon isotope in the patient's breath.

Here's an overview of how the urease breath test works:

1. Urea Solution Ingestion: The patient drinks a solution containing urea, which is a compound that can be broken down by the enzyme urease, produced by H. pylori bacteria. The urea used in the test contains a specific isotope of carbon, such as carbon-13 or carbon-14.

2. Urease Activity and Carbon Isotope Exchange: If H. pylori is present in the stomach, the urease enzyme produced by the bacteria will break down the urea in the solution, releasing the carbon isotope into the stomach's atmosphere.

3. Absorption and Exhalation: The released carbon isotope is absorbed into the bloodstream and carried to the lungs. When the patient exhales, the carbon isotope is expelled in the breath.

4. Breath Sample Collection: The patient's breath is collected in a special bag or tube for analysis.

5. Measurement of Carbon Isotope: The carbon isotope concentration in the breath sample is measured using a mass spectrometer or another analytical technique.

6. Interpretation of Results: The level of carbon isotope in the breath sample is compared to a reference range. A higher-than-normal level of carbon isotope indicates the presence of H. pylori infection in the stomach.

The urease breath test is a non-invasive and relatively simple procedure. It can be performed in a clinic or doctor's office and does not require the use of radiation or endoscopy. It is commonly used as a first-line test for diagnosing H. pylori infection and can help guide treatment decisions, including the use of antibiotics to eradicate the bacteria.