Urea Breath Test

The urea breath test (UBT) is based on Helicobacter pylori urease activity, and the ingestion of labeled urea results in the production of labeled carbon dioxide which then can be detected in the breath. Urea can be labeled with two different isotopes, 14C (the radioactive isotope) or 13C (the nonradioactive stable isotope). Although 14C-labeled urea is inexpensive, 13C-labeled urea is more stable and nonradioactive, so it is widely used in clinical practice. The test protocol is not completely standardized. Factors such as urea dose, whether or not fasting before test, whether a test meal is used, and type of the test meal can affect test accuracy. In general, fasting for > 4 h before the test is recommended, and breath sampling is performed 20–30 min after ingestion of the urea substrate. In general, the use of citric acid test meal is recommended. Nevertheless, UBT is a noninvasive, simple, and safe test which provides excellent accuracy both for the diagnosis of H. pylori infection and for the confirmation of successful H. pylori eradication