A package of Breath collection card and urea capsule

The Urea Breath Test is based on the ability of the H. pylori enzyme urease to cleave urea into ammonia and carbon dioxide. As the urease enzyme is not present in mammalian cells, the presence of urease (and the products of urea cleavage) in the stomach is evidence that H. pylori bacteria are present. To detect H. pylori, urea labeled with 14C is swallowed by the patient. If gastric urease from H. pylori is present, urea is split to form CO2 and NH3 at the interface between the gastric epithelium and lumen and 14CO2 is absorbed into the blood and exhaled in the breath. Exhaled breath samples can then be collected and measured by the detector.