Allergy

Deamidated Gliadin Test (IgG) — Support Coeliac Disease Diagnosis

Deamidated gliadin is a modified form of the gluten protein gliadin that is produced during digestion. In individuals with coeliac disease, the immune system reacts to deamidated gliadin by producing IgG antibodies. This test is particularly useful as a complementary marker alongside tissue transglutaminase (tTG) testing, and can be especially helpful in children under two years old where tTG antibodies may not yet be reliably present.

Why Test Deamidated Gliadin Test?

This test is recommended as part of coeliac disease screening, particularly when tissue transglutaminase results are borderline, in young children being evaluated for coeliac disease, or when there is clinical suspicion of coeliac disease despite other test results. It is also useful for monitoring dietary compliance in diagnosed coeliac patients.

What Do High Deamidated Gliadin Test Levels Mean?

Elevated IgG antibodies to deamidated gliadin suggest an immune response to gluten that is highly suggestive of coeliac disease. A positive result should be followed up with additional testing, potentially including intestinal biopsy, for a definitive diagnosis.

What Do Low Deamidated Gliadin Test Levels Mean?

Low or negative antibody levels make coeliac disease less likely, though they cannot entirely rule it out, especially if you have IgA deficiency. Results should be interpreted together with tTG and total IgA levels.

Symptoms to Watch For

  • Chronic diarrhoea or constipation
  • Abdominal bloating and pain
  • Unexplained weight loss
  • Fatigue and weakness
  • Iron deficiency anaemia
  • Mouth ulcers or dental enamel defects
  • Skin rash (dermatitis herpetiformis)

Who Should Get Tested?

  • People with suspected coeliac disease symptoms
  • Children under 2 years being screened for coeliac disease
  • Those with borderline tissue transglutaminase (tTG) results
  • Individuals with IgA deficiency who need alternative coeliac markers
  • Diagnosed coeliac patients monitoring dietary compliance

How to Prepare for Your Test

You must be eating gluten regularly (daily for at least 2-3 weeks) before taking this test for accurate results. Do not start a gluten-free diet before testing. Bring valid ID to your appointment.

Frequently Asked Questions

What is deamidated gliadin?
Deamidated gliadin is a modified form of gliadin, a gluten protein found in wheat. During digestion, the enzyme tissue transglutaminase modifies gliadin, making it more recognisable to the immune system in coeliac disease.
Is this test enough to diagnose coeliac disease?
No single test can definitively diagnose coeliac disease. This test is most useful when combined with tissue transglutaminase, total IgA, and potentially an intestinal biopsy.
Do I need to eat gluten before the test?
Yes. You should eat gluten daily for at least 2-3 weeks before the test. Going gluten-free before testing can produce false negative results.
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Medical Disclaimer

The information on this page is provided for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment. Wellth provides health information and testing services but is not a substitute for clinical care. Always consult a qualified healthcare provider if you have questions about a medical condition. If you are experiencing severe or urgent symptoms, contact your doctor or call 1177 Vårdguiden. Blood test results should be interpreted by a qualified healthcare professional in the context of your complete medical history.