Urea Breath Testing in General Practice - NAT
Diagnosing H. pylori
By Dr Wessel Jenner
Published July 2019
Helicobacter Pylori (H. pylori) is a spiral shaped gram-negative bacteria that colonises the mucous layer of the stomach.
H. pylori causes a chronic inflammatory reaction in the mucous layer and can lead to an increased risk of developing peptic ulcers, duodenal ulcers or some cancers of the stomach.
Infection appears to be acquired during childhood and persists lifelong unless treated. It is postulated that one can become infected by contact with saliva, vomit or stools of an infected person. It’s unusual to catch the infection as an adult.
The urea breath test is an accurate, safe and quick way to diagnose H. pylori.
14C-Urea Breath Testing - Clinical Recommendations
- People with duodenal or stomach ulcers.
- People with non-ulcer dyspepsia.
- Monitoring the success of eradication of H. pylori infection.
- In some cases, family members of infected people.
How does the test work?
The H. pylori bacteria is very effective in breaking down urea into CO2 and ammonia to create an environment in the stomach for it to survive. During the urea breath test, the patient is given a capsule that contains urea labelled with 14C. The H. pylori, if present, will break down the urea quickly and release the 14C in the form of 14CO2 that is exhaled. The 14CO2 is collected in a balloon and sent to a laboratory where the 14CO2 content is measured.
If the bacteria is not present, the labelled urea will not be broken down and the breath will not contain 14CO2.
How safe is this test?
14C is a rare, naturally occurring radioactive form of carbon, as opposed to the more common occurring 12C. The radiation exposure during the test is far less than that of a standard X-ray. Studies have not been done to determine safety in pregnancy, or for breast feeding mothers and children so use in these groups is not recommended unless there are special circumstances.
As an alternative in these cases a stool antigen test can be ordered.
![This image depicts urea breath test is as a way to diagnose h. pylori.. Professional medical imaging for clinical reference and educational purposes. [umbracoNodeId=12084]](/assets/image/jpeg/urea-breath-test-is-as-a-way-to-diagnose-h-pylori-3dpb1anyybz2ubusgjyy9j.jpg)
Helicobacter pylori bacteria colonising the stomach.
Patient preparation
To avoid inaccurate results, the following precautions should be taken:
- Patient should fast for at least 4 hours before the test (including water).
- The following medication should be discontinued to prevent false negative results:
| Precaution | When |
|---|---|
| Antibiotics and bismuth containing products | 4 weeks before test |
| Cytoprotectives, e.g. Sucralfate | 2 weeks before test |
| Proton pump inhibitors | 1 week before test |
| H2-antagonists and antacids | During fasting and during test |
Cost
Bulk billed subject to Medicare criteria.
About the Author
Dr Wessel Jenner
BSc MBChB FRCPA- Chemical Pathology
- Vitamin D Testing
- Diabetes Management
- Thyroid Function
- Hormone Testing
Dr Jenner began training in Chemical Pathology in 2001 and obtained Fellowship from the Colleges of Medicine of South Africa in 2004, as well as a Master’s degree in Chemical Pathology from the University of Pretoria in 2005. He has worked as a senior registrar in Clinical Biochemistry at the Royal Infirmary of Edinburgh, as a consultant clinical biochemist at the NHS Borders Hospital (Scotland), and as a consultant chemical pathologist in private practice in South Africa. In 2012, Dr Jenner relocated to Australia and worked as a senior registrar at the Royal Brisbane and Women’s Hospital. He obtained his Fellowship from the Royal College of Pathologists of Australasia in 2013 and joined Australian Clinical Labs in early 2014.