Quick Reference
- Full form
- Anti Tissue Transglutaminase, IgA (tTG-IgA)
- Sample type
- Blood
- Fasting
- Not required
- Marker measured
- 1
- Report turnaround
- After 3 days
- Available at
- All locations
About Anti Tissue Transglutaminase (IgA)
Anti tTG IgA is the primary blood test used to screen for celiac disease today, more reliable than the older gliadin antibody tests. It checks for antibodies against an enzyme your gut reacts to when gluten triggers an immune response.
No fasting is required, but you must keep eating gluten normally before this test, since stopping beforehand can lower antibody levels and lead to a false negative result.
How to Prepare
- No fasting required.
- Keep eating gluten as usual before testing, stopping early can hide a true result.
Frequently Asked Questions
Is Anti tTG IgA the main test for celiac disease?
Yes, it is currently considered the most reliable first-line blood test for celiac disease.
Should I avoid gluten before this test?
No, continue eating gluten normally, since stopping beforehand can cause a falsely negative result.
Do I need to fast before this test?
No fasting is required.
What if my IgA levels are naturally low?
Your doctor may also order an IgG version of this test, since IgA deficiency can affect the accuracy of this specific test.
How soon will my report be ready?
After 3 days, given the specialised antibody processing involved.
Is home sample collection available?
Yes, in all City Care Lab service areas.
This page provides general health information and is not a substitute for medical advice. Speak with your doctor about your specific results and treatment.