Stool
Gluten intolerance: anti-gliadin and anti-transglutaminase
Investigation of anti-gliadin and anti-transglutaminase in stool, relevant for suspected gluten intolerance.
€ 185,00
All tests
Gut · Stool
Anti-transglutaminase IgA (feces)
Celiac disease antibodies measured in the stool instead of in blood; not suitable for diagnosing celiac disease.
At a glance
- Measured in stool
- In 1 test panel
- No special preparation
Explanation
Anti-transglutaminase IgA (feces): what is measured?
In celiac disease, the immune system makes antibodies of the IgA type against tissue transglutaminase (tTG), a protein of the body's own in the gut wall. In the blood, that is the first test when celiac disease is suspected. This test measures the same kind of antibodies in a stool sample. This measurement has not been validated and is something different from the blood test.
What can it detect?
- A reaction of the immune system in the gut against tissue transglutaminase; not suitable for detecting celiac disease
Result
What does the result mean?
Anti-transglutaminase IgA (feces) too high
A raised value means that antibodies against tissue transglutaminase have been found in the stool. How often this occurs in celiac disease, and how often in people without celiac disease, has not been well studied. The result does not show celiac disease. With symptoms that may fit celiac disease, a blood test (tTG IgA with total IgA) is the appropriate next step.
Anti-transglutaminase IgA (feces) too low
A low value does not rule out celiac disease. People who already eat gluten-free or low-gluten, or who have an IgA deficiency, can also have a low value. With symptoms that may fit celiac disease, a blood test is still needed.
After an abnormal result
With a raised value, the GP arranges a blood test for celiac disease if you have symptoms or a higher risk (tTG IgA with total IgA). If that is raised, a referral to a gastroenterologist follows. Do not stop eating gluten on your own initiative before that test, because the diagnosis can then no longer be made properly.
Reliability
How reliable is the test?
According to the Dutch medical specialists' guideline (FMS) on celiac disease and the Dutch GP guideline (NHG), celiac disease is diagnosed with blood tests (tTG IgA in the blood, together with total IgA) and usually a biopsy from the small intestine, not with antibodies in the stool. Anti-transglutaminase IgA in the stool has not been validated: it has not been shown that the measurement reliably detects or rules out celiac disease.
What can affect the result?
- The result is only meaningful if you eat gluten; on a gluten-free or low-gluten diet, the antibodies fall.
- With an inborn deficiency of IgA (IgA deficiency), the value can be low, even with celiac disease.
- Measurement methods and cutoff values are not standardized and differ per laboratory.
- Bowel inflammation or loose stool can change the amount of antibodies in a stool sample.
Who it is for
Who is the test useful for?
Useful for
This test is not useful for detecting or ruling out celiac disease. If you have symptoms that may fit celiac disease, such as long-lasting abdominal symptoms, diarrhea, unexplained weight loss or an unexplained iron deficiency, or a parent, brother, sister or child with celiac disease, it is better to have a blood test (tTG IgA with total IgA) while you keep eating gluten as usual.
How common is it?
About 1 in 100 people in the Netherlands has celiac disease; many of them do not know it. In people with a parent, brother or sister with celiac disease, it is about 10 in 100. How often these antibodies in the stool are raised in people without celiac disease is not known.
Thuisarts.nl (NHG)
Drawbacks and risks
- If you start eating gluten-free yourself after a raised value, the blood test and the gut biopsy become unreliable and you may follow a strict diet unnecessarily.
- A low value can give false reassurance: this test does not rule out celiac disease.
Get tested
Anti-transglutaminase IgA (feces): test panels
Anti-transglutaminase IgA (feces) is part of these test panels. You order online and have your blood drawn at a collection point or collect the sample at home.
Evidence
Sources
This explanation is based on Dutch guidelines and independent information. It is general information, not a diagnosis. Discuss an abnormal result with your GP.
More about risks and results- FMS Richtlijnendatabase: Prikkelbaredarmsyndroom, module Gebruik calprotectine-test
- NHG-Standaard Prikkelbaredarmsyndroom (PDS)
- NVKC, allesovertesten.nl: Calprotectine
- Thuisarts.nl: Ik krijg onderzoek om uit te zoeken of ik de ziekte van Crohn heb
- FMS Richtlijnendatabase: Coeliakie en glutengerelateerde aandoeningen, module Serologische diagnostiek bij volwassenen
- NHG-Standaard Voedselovergevoeligheid en coeliakie
- NVKC, allesovertesten.nl: Anti-TTG
- Thuisarts.nl: Ik heb coeliakie
More explanations
Other tests: Gut
- Acetate and propionate production
- Acetate- and propionate-forming bacteria
- Acetic acid (feces)
- Acetic acid, relative (feces)
- Akkermansia, activity
- Alpha-1 antitrypsin (feces)
- Anti-gliadin IgA (feces)
- Aspergillus fumigatus (feces)
- Aspergillus niger (feces)
- Bacteroides group, activity
- Beta-defensin 2 (feces)
- Bifidobacteria group, activity