LOINC Code 29891-9: CO2 post dose urea Ql (Exhl gas)

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Carbon dioxide^post dose urea. It is commonly used with the system or sample type Exhl gas.

When is it used?

• Used in lab systems, EHRs, and clinical data exchange.
• May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
• Status: ACTIVE
• Order vs observation: Both

What it does not mean

• The code identifies the observation or test, not the actual result.

Key facts

• Helicobacter pylori [Presence] in Stomach by urea breath test
• Carbon dioxide^post dose urea
• The patient ingests C-14 or C-13 labeled urea , the clinic collects the patients exhaled breath and the lab measures the amount of the chosen isotope in the exhaled CO2. H pylori produces urease that digests urea to produce CO2. The most common isotope is C13 which is detected by infrared spectroscopy. Tagged CO2 in the breath is evidence of gastric Helicobacter pylori infection.
• After; Breath; Carbamide; Carbonic anhydride; cO2; ExG; Exhaled gas; Exhaled gas (=breath); Gases; Gastro; Gastroenterology; GI; Helicobacter pylori breath test; Microbiology; Ordinal; p dose; p urea; Point in time; PR; PST; QL; Qual; Qualitative; Random; Screen; UBT; UniversalLabOrders; Urea breath test

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Related SNOMED CT concepts

Related observations and tests

Common synonyms

Frequently asked questions