The urea breath test is a rapid diagnostic procedure used to identify infections by Helicobacter pylori, a spiral bacterium implicated in gastritis, gastric ulcer, and peptic ulcer disease. Diagnosis (from the Greek words dia = by and gnosis = knowledge) is the process of identifying a disease by its signs, symptoms and results of various diagnostic procedures. ... An infection is the detrimental colonization of a host organism by a foreign species. ... Binomial name Helicobacter pylori (Warren & Marshall, 1983) Helicobacter pylori is a bacterium that infects the mucus lining of the human stomach. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Gastritis is a medical term for inflammation of the lining of the stomach. ... I LOVE BIBI ...

Principles and mechanism

Patients swallow urea labelled with an uncommon isotope, either radioactive carbon-14 or non-radioactive carbon-13. In the subsequent 10-30 minutes, the detection of isotope-labelled carbon dioxide in exhaled breath indicates that the urea was split; this indicates that urease (the enzyme that H. pylori uses to metabolize urea) is present in the stomach, and hence that H. pylori bacteria are present. Urea is an organic compound of carbon, nitrogen, oxygen and hydrogen, with the formula CON2H4 or (NH2)2CO and the structure shown right: Urea is also known as carbamide, especially in the recommended International Non-proprietary Names (rINN) in use in Europe. ... Isotopes are forms of an element whose nuclei have the same atomic number–-the number of protons in the nucleus--but different atomic masses because they contain different numbers of neutrons. ... Radioactivity may mean: Look up radioactivity in Wiktionary, the free dictionary. ... Carbon-14 is the radioactive isotope of carbon discovered February 27, 1940, by Martin Kamen and Sam Ruben. ... Carbon-13 is a stable isotope of carbon. ... Carbon dioxide is an atmospheric gas composed of one carbon and two oxygen atoms. ... Helicobacter Pylori Urease drawn from PDB 1E9Z. Urease (EC 3. ... Ribbon diagram of the catalytically perfect enzyme TIM. Factor D enzyme crystal prevents the immune system from inappropriately running out of control. ... Santorio Santorio (1561-1636) in his steelyard balance, from Ars de statica medecina, first published 1614 Metabolism (from μεταβολισμος (metabolismos), the Greek word for change, or overthrow (Etymonline)), is the biochemical modification of chemical compounds in living organisms and cells. ... The stomach (Gaster) In anatomy, the stomach (in ancient Greek στόμαχος) is an organ in the alimentary canal used to digest food. ...

For the two different forms of urea, different instrumentation is required; carbon-14 is normally measured by scintilation, carbon-13 by isotope ratio mass spectrometry (IRMS). For carbon 13 a baseline sample before taking urea is required for comparison with the post urea sample. Mass spectrometry is a technique for separating ions by their mass-to-charge (m/z) ratios. ...

The difference between the pre and post urea measurements is used to determine infection. This value is compared to a cut-off value. Results below the value are assumed to be negative, those above positive. The cut-off value itself is determined by comparing the results of patients with two or more different detection methods. The value is chosen that gives the best combination of sensitivity and specificity. See: Sensitivity (electronics) Sensitivity (human) Sensitivity (tests) For sensitivity in finance, see beta coefficient This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... In binary testing, e. ...

The test measures active H. pylori infection. If antibiotics are depressing the amount of H. pylori present or the stomach conditions are less acidic than normal the amount of urease present will be lessened.

Accordingly the test should only be performed 14 days after stopping acid reducing medication (proton pump inhibitors ('PPI')) or 28 days after stopping antibiotic treatment. Some clinicians believe that a reservoir of H pylori in dental plaque can affect the result. Proton pump inhibitors are a group of drugs whose main action is pronounced and long-lasting reduction of gastric acid production. ...

References

• Surveyor I, Goodwin CS, Mullan BP, Geelhoed E, Warren JR, Murray RN, Waters TE, Sanderson CR. The ¹⁴C-urea breath-test for the detection of gastric Campylobacter pylori infection. Med J Aust. 1989; 151(8):435-439. PMID 2593958.

See also

• Rapid urease test (done on biopsy specimens after upper endoscopy)