Tissue transglutaminase (TG) IgA antibody (serum/plasma)
This test measures antibodies against tissue transglutaminase, a protein involved in gluten metabolism. It helps diagnose celiac disease, an autoimmune condition triggered by gluten.
["Helps detect celiac disease by checking for gluten-related immune responses."]
Key facts at a glance
- LOINC
- 27999-2
- Short code
- T gondii DNA Amn Ql NAA+probe
- Synonyms
- T gondii DNA Amn Ql NAA+probe
- Category
- chemistry
- Sample
- fluid
- Container
- Sterile tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- Specimen volume
- 2-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- Hemolysis max
- 300
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Celiac disease occurs when your immune system mistakenly attacks the small intestine after eating gluten, a protein found in wheat, barley, and rye. Tissue transglutaminase is a protein in the intestine that gets altered by gluten, triggering an immune response. High levels of anti-tTG antibodies suggest gluten sensitivity or celiac disease.
How the Test Works
A small blood sample is taken from your arm. The lab uses an immunoassay (a test that detects specific antibodies) to measure your levels of anti-tTG IgA antibodies in your serum or plasma.
What to Expect Before the Test
No special preparation is needed, but you may want to avoid gluten-containing foods for a few days before testing if your doctor recommends it. Let your doctor know about any medications or supplements you’re taking, as they could affect results.
Possible Results and Next Steps
If your results are positive, your doctor may recommend further testing, such as a gluten-free trial or an intestinal biopsy, to confirm celiac disease. A negative result doesn’t rule out celiac disease entirely, so follow-up testing may still be needed.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Anti-tTG IgA antibodies are a key marker for diagnosing celiac disease. While IgA deficiency can sometimes cause false negatives, this test is highly sensitive for detecting gluten-related damage. Early diagnosis is crucial because untreated celiac disease can lead to malnutrition, damage to the small intestine, and other long-term health issues. If you have symptoms like persistent diarrhea, weight loss, fatigue, or unexplained anemia, this test may be part of your evaluation.
Short name
IgA Anti-Tissue Transglutaminase (tTG) Antibody
Frequently asked questions
What symptoms might trigger this test?
Can I eat gluten before this test?
Does this test differ from a gluten sensitivity test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy