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IgG Antibody to Wheat Gluten (Tissue Transglutaminase) - Serology

Published: August 9, 2026Updated: August 17, 2026

This test measures the level of antibodies your body produces in response to gluten, a protein found in wheat. It helps identify potential celiac disease or gluten sensitivity.

Quick summary

["This test helps determine if gluten may be triggering an immune reaction in your digestive system."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
103126-9
Short code
Wheat (nTri a) 19+20+21 IgE RAST
Synonyms
Wheat (nTri a) 19+20+21 IgE RAST
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
10
Ref high
40
Critical range
— – 500 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
rast
CPT
84484
SNOMED
302774002
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms like persistent diarrhea, stomach pain, weight loss, or fatigue, especially if you’ve been diagnosed with or suspect celiac disease. It may also be used as part of a broader evaluation for gluten-related disorders.

What to Expect Before the Test

No special preparation is needed, but you may be asked to avoid gluten-containing foods for a few days before testing. Bring a list of medications to your appointment, as some may affect results.

What the Test Involves

A blood sample will be taken from a vein in your arm. The sample is sent to a lab for analysis to detect specific antibodies against gluten proteins.

What the Results Mean

High levels of these antibodies suggest an immune response to gluten, which may indicate celiac disease or gluten sensitivity. Your doctor will discuss results with you and may recommend further testing or dietary changes.

Reference range

Adult: 10-40 U/LN/A

Specimen: serum

No special preparation required. Avoid fatty meals before the test if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

IgG Anti-TTG Antibody (Wheat Gluten Screening)

Frequently asked questions

Celiac disease is an autoimmune condition where gluten triggers an immune reaction that damages the small intestine. This test helps confirm whether gluten is causing digestive issues or other symptoms by detecting specific antibodies in your blood.
If your test results are positive, your doctor may recommend a gluten-free diet to see if symptoms improve. If you have gluten sensitivity but no celiac disease, you may still experience symptoms even on a gluten-free diet.
What Does a Positive Result Mean?
A positive result means your body is producing antibodies against gluten, which may indicate celiac disease or gluten sensitivity. Follow-up testing, such as an endoscopy or genetic testing, may be needed to confirm the diagnosis.
Will This Test Detect All Types of Gluten-Related Disorders?
This test primarily screens for antibodies against tissue transglutaminase, a marker for celiac disease. Other gluten-related disorders, like non-celiac gluten sensitivity or wheat allergy, may require different tests or evaluations.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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 17, 2026. · Read our editorial policy