London Gastroenterology Partnership are proud to offer a range of hydrogen/methane breath tests for the investigation of intolerance to common dietary components, such as lactose and fructose, but also for detection of Helicobacter pylorii and small bowel bacterial overgrowth.
What is a hydrogen/methane breath test?
The test is based on breath hydrogen and methane analysis and provides information about the digestion of certain sugars or carbohydrates, e.g. milk sugar (lactose) or fruit sugar (fructose). The pattern and quantity of hydrogen produced in your exhaled breath at intervals during the test will help determine if you are intolerant to, or have difficulty in processing or absorbing certain sugars. As about 30% of the population do not secrete hydrogen in measureable quantity, the hydrogen/methane test is considered to be the gold standard at present.
How does it work?
Hydrogen and methane gas in the body is produced from intestinal bacteria. Bacteria, normally in the large intestine, produce hydrogen and methane through fermentation of carbohydrates - such as lactose, fructose and other sugars. Some of the hydrogen and methane produced by bacteria is absorbed by intestinal mucosa into the bloodstream and is transported to the lungs, where it can be detected in the breath.
Normally, such sugars are broken down and absorbed in the small intestine and very little reaches the large intestine to be fermented by bacteria. However, a number of adults develop a reduced ability to process and absorb certain sugars in the small intestine. They are therefore carried forward to the colon where they are metabolised by colonic bacteria producing a large amount of hydrogen and methane that is measured in the breath.
What symptoms might I have to suggest a possible benefit from hydrogen breath testing?
There are a number of digestive symptoms which may arise from the malabsorption of sugars, and consequent production of excessive gas in the large bowel. These include:
- Abdominal cramping
- Loose stools
Some people also report other symptoms, when they eat foods containing sugars which they are unable to digest. Some examples include:
- Restlessness or irritability
- Cold or heat sensations/tingling
On arrival at the Day Unit, one of the staff will complete a brief questionnaire with you to check on your symptoms and that there is no problem in doing the test. You will then be asked to breathe out into a bag to collect the first breath hydrogen/methane sample. After drinking the test sugar solution (e.g. lactose) further breath samples will be collected every 15 to 30 minutes for the next 2- 3 hours, depending on the results or information required. You will be asked to rate your symptoms at the time of each breath sample and these answers will be documented.
Alternatively a test kit can be sent to your home together with a DVD on how to perform the test. You can then undertake the test at your convenience and return the specmen bags to us. A pre-paid label will be enclosed.
How long does a hydrogen/methane breath test take?
The test takes between 2 and 3 hours.
Are there any risks or side effects?
The test is very safe, and, apart from the possible reproduction of some or all of your symptoms for a short time, has no significant side effects or risks.
When do I get the results?
A full report, including symptom and breath hydrogen analysis and interpretation, will be sent to you and your doctor within one week of the test.
What does it mean if the test is positive?
This suggests that some or all of your digestive symptoms may be due to your being unable to process certain sugars adequately in the bowel.
What can be done if the test is positive?
If the test shows that you are unable to absorb certain sugars, you may benefit from a formal dietetic assessment and advice. This can be organised by the London Gastroenterology Partnership.
I would like a hydrogen breath test.
The test costs £300 carried out at Parkside Hospital or £335 if it were to be carried out at home. You can refer yourself to this service; you do not need a letter of insurance or referral from a professional. For further information, or to make an appointment, please call the Daycare Unit at Parkside Hospital on 020 8605 2888 or London Gastroenterology Partnership on 020 8337 9609.