14C-urease respiratory test for the determination of Helicobacter pylori

14C-urea breath test is a test for the determination of Helicobacter pylori (Helicobacter pylori), a non-invasive diagnosis of H. pylori, which is based on the ability of H. pylori to produce the enzyme urease. Under the action of urease in the stomach, urea is broken down to ammonia and labeled carbon dioxide. Carbon dioxide enters the bloodstream and is excreted from the body through the lungs, while the carbon content in the exhaled air increases.

The principle of the test: During the test, the patient takes the drug Ureacapsule (harmless to health, containing 14C carbon in its composition). 14C is a stable natural isotope of carbon that is present in the human body and makes up about 1% of total cells. If H.pylori bacteria are present in the stomach, urea is hydrolyzed under the effect of urease bacteria, and carbon dioxide is formed. Carbon dioxide containing the 14C label is absorbed into the blood and released as part of exhaled air. After capsule administration in patients infected with H.pylori bacteria, the maximum manifestation of 14CO2 on exhalation is observed between 10 and 30 minutes and decreases according to a half-life of 15 minutes. About 10% of 14CO2 is absorbed and then gradually excreted in the urine with a half-life of about 40 hours.

If the patient is not infected with H.pylori, the ingested labeled urea is absorbed in the gastrointestinal tract and distributed in the extracellular and intracellular fluid. Within 3 days, about 88% of urea is excreted from the body in urine.

Advantages:

Accuracy: Sensitivity is 95-98%, specificity is 95%-100%.
Convenience: A non-invasive procedure that does not require the insertion of an endoscope and is well tolerated by patients. This analysis can be repeated the required number of times without restrictions.
Informative: The results of the test reflect the activity of the microbe on the entire surface of the stomach rather than on specific areas of the stomach (reduces the risk of false negatives). Allows a quantitative assessment of the microbe in dynamics.
Safety: The method involves exposure to negligible doses of isotopes and has therefore been exempted from regulatory restrictions on use in the US and China. The method can be applied in both adults and children. It has no contraindications or side effects.
Simplicity: Simple manipulation that does not require special handling.
Speed: It takes 30-60 minutes to complete the test.