The rapid urease test

What is a rapid urease test?

A rapid urease test is used to detect the Helicobacter pylori bacterium. The bacterium contains the enzyme urease, which can break down urea into carbon dioxide and ammonia. The test can detect this reaction by changing the pH value. The change in pH value is shown by a color indicator.

The test is used in everyday clinical practice as part of a gastroscopy. The removed tissue can be reliably tested for the bacterium.

The indications for a rapid urease test

The urease rapid test is carried out if chronic gastritis is suspected. Gastritis describes an inflammation of the stomach lining, which is accompanied by abdominal pain, nausea and heartburn.

Especially if the cause of gastritis is unclear or an infection with Helicobacter pylori is suspected, a gastroscopy, i.e. a gastroscopy, should be performed. The removed tissue can then be examined using the rapid test.

Find out all about the topic here: Helicobacter pylori.

When does a rapid urease test make no sense?

If the exact cause of the gastric mucosa is known, no gastroscopy (gastroscopy) with tissue removal is required. This intervention would then be superfluous.

Even if the suspicion of a colonization of the stomach with Helicobacter pylori seems unlikely, this test should not be carried out. There are other alternatives to diagnose this bacterium that are less invasive.

Also read the article: The symptoms of Helicobacter pylori infection.

Can I buy a rapid urease test from the pharmacy without a prescription?

The urease rapid test cannot be purchased in a pharmacy or tissue from the gastric mucosa is required to perform it. This tissue can actually only be removed through a gastroscopy. For this reason, a private person cannot perform the rapid urease test.

However, there are other alternatives on the market that can be purchased without a prescription. For example, there are tests that can detect the Helicobacter pylori antibodies in the blood or the antigen of the bacterium in the stool.

Can you do this at home or is it only possible at the doctor's?

As already explained above, the urease rapid test can only be carried out by a doctor. This is because tissue from the gastric mucosa is required for the test, which is taken in a gastroscopy. However, there are other test options available that can be carried out at home. The bacterium can be detected in whole blood or in stool.

If the test result is positive, however, you should definitely consult a doctor who will confirm this result again and, if necessary, initiate therapy. Helicobacter pylori infection should not be underestimated as it can lead to chronic gastric inflammation. In the worst case, stomach ulcers and malignant changes can even develop, which is why a medical examination is essential.

Also read the article: The eradication of Helicobacter pylori.

The implementation

The patient is first prepared for the gastroscopy. The throat is first anesthetized for the examination. If desired, you can also get drugs that have a calming effect and take away the fear of the examination. Then the doctor examines the throat and stomach lining with a special device (so-called endoscope). Then he takes a small piece of tissue from a place that seems suspicious to him.

The removed tissue is then placed on a special nutrient medium. This nutrient medium mainly contains urea, which can be broken down by the bacterial urease enzyme. This nutrient medium also contains a color indicator solution that changes when the pH value changes. This means that when urea is broken down, ammonia is produced, which leads to a change in the pH value and this can be detected in terms of color.

Find out more about the topic here: The gastroscopy.

The evaluation

The evaluation of this test is quite simple - the test is based on a change in the pH value. This change can be recognized by a color change.
A red color change indicates a positive result, whereas a yellow color change indicates a negative result.

The urease rapid test is a relatively reliable test with high sensitivity and specificity. However, the result can be falsified if the enzyme activity is inhibited. This can be done by taking proton pump inhibitors or antibiotics. For this reason, the intake of proton pump inhibitors should be discontinued one week and the intake of antibiotics six weeks before the examination.

Can the rapid test also be false positive?

The test can also be positive even though you do not have a Helicobacter pylori infection. This can occur when another bacterium overgrows the stomach.

Usually two positive test results or one positive histological examination are required for the diagnosis. In a histological examination, the removed tissue is examined more closely under a microscope. If you can see the bacteria here, you are suffering from a Helicobacter pylori infection that needs treatment.

The duration

The duration of the examination actually depends on the duration of the gastroscopy. If the examining doctor has looked at all areas, the tissue can be removed. The removal takes one to two minutes.

Then a piece of the tissue is placed on the special nutrient medium or the test and the color change is awaited. This also only takes a few minutes. The examination is then ended.

When should I repeat the rapid urease test?

As a rule, the rapid test does not have to be repeated. If a diagnosis of Helicobacter pylori infection has been made, therapy can be started. In order to be able to assess the success of the therapy, other test methods that are less invasive are used. This includes the breath test and the stool test (see section alternatives).

Also read the article: The eradication of Helicobacter pylori.

The costs

The costs of the gastroscopy and the urease rapid test are usually covered by the health insurance company, as this is a necessary examination. However, if you are unsure, you can get information from your health insurance company in advance or ask your doctor.

What are the alternatives?

The diagnosis of Helicobacter pylori can be divided into two procedures. The first procedure is invasive - i.e. by removing tissue. The urease rapid test or microscopic examination of the tissue can be carried out here.

The second procedure is non-invasive. On the one hand, the antigens (special surface structure) of the bacterium in the stool can be detected here. The 13C breath test can also be performed. For this test, the patient drinks a juice that also contains urea. This urea is marked with the 13C isotope. After half an hour the patient has to exhale into a bag in which the concentration of the labeled carbon monoxide is measured.
Antibody determination is another alternative. For this purpose, blood is drawn from the patient, which is examined for specific antibodies against Helicobacter pylori.

Find out more about the Breath test for the detection of a Helicobacter pylori infection.