Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test
About Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test
| Field | Value |
|---|---|
| Also Known As | Anti-tTG IgG, tTG IgG antibody test, Tissue transglutaminase IgG test, TTG IgG |
| Sample Type | Venous blood (serum) |
| Fasting Required | No fasting required |
| Report Time | 1 to 3 working days |
| Recommended For | All ages; particularly individuals with IgA deficiency suspected of coeliac disease |
| Price | Starting at ₹1,100 |
What Is a Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test?
The tissue transglutaminase IgG antibody (anti-tTG IgG) test measures IgG-type antibodies directed against tissue transglutaminase, an enzyme that the immune system mistakenly attacks in people with coeliac disease.
A doctor may order this test when coeliac disease is suspected, especially in patients who have a known IgA deficiency. The sample collected is a small amount of venous blood from the arm. This test is also referred to as the anti-tTG IgG test or the tTG IgG antibody test.
What Does a Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test Measure?
The tissue transglutaminase IgG test looks for one specific type of antibody in your blood. The table below describes what is measured and why it matters.
| Parameter | What It Tells Us |
|---|---|
| tTG IgG antibody level | Indicates whether the immune system is producing IgG antibodies against tissue transglutaminase, which points to possible coeliac disease, particularly in individuals with IgA deficiency. |
A positive result is consistent with coeliac disease. It is especially meaningful for people whose bodies do not produce enough IgA antibodies, as they would not show up accurately on standard IgA-based tests.
Why Is a Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test Done?
This test helps doctors investigate digestive symptoms and suspected gluten-related conditions. The sections below explain when it is typically ordered.
Common Symptoms That May Require This Test
A doctor may recommend the anti-tTG IgG test if you experience any of the following:
- Persistent or recurring diarrhoea
- Bloating and abdominal discomfort
- Unexplained weight loss
- Fatigue and general weakness
- Greasy or foul-smelling stools (a sign of poor nutrient absorption)
- Iron-deficiency anaemia that does not respond to treatment
- Tingling or numbness in the hands or feet
- An itchy, blistering skin rash known as dermatitis herpetiformis
Conditions This Test Can Help Detect
The tissue transglutaminase antibody IgG test can help identify the following conditions:
- Coeliac disease (also called gluten-sensitive enteropathy), including cases with atypical or mild symptoms
- Dermatitis herpetiformis, a skin condition closely linked to gluten sensitivity
- Coeliac disease in individuals with IgA deficiency, where standard IgA-based tests may not give accurate results
Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test for Chronic Disease Monitoring
Once a patient has been diagnosed with coeliac disease and starts a gluten-free diet, this test can be repeated at intervals to check whether antibody levels are falling. Persistently high levels after dietary changes may indicate that gluten is still being consumed, knowingly or unknowingly.
Note that IgG antibodies may take longer to normalise compared to IgA antibodies, sometimes more than a year after starting the diet.
How to Prepare and What to Expect
Preparing correctly for this test is straightforward, but one step is particularly important: staying on a gluten-containing diet before the test.
Do You Need to Fast?
No fasting is required before the anti-tTG IgG test. You can eat and drink normally on the day of sample collection.
Practical Tips Before Your Test
Keep the following points in mind before going for the tissue transglutaminase IgG test:
- Continue eating foods that contain gluten (such as bread, roti, and pasta) for at least two weeks before the test, or as advised by your doctor. Starting a gluten-free diet before testing can give inaccurate results.
- For a more thorough pre-test period, some doctors recommend consuming the equivalent of four to six slices of bread daily for six to eight weeks.
- Inform your doctor about any medications, supplements, or steroids you are currently taking.
- Stay well hydrated before the blood draw, as this makes the vein easier to access.
- Wear a short-sleeved or loose-sleeved top for easy access to the arm.
Step-by-Step Procedure
Here is what happens during a typical blood collection for this test:
- A trained phlebotomist cleans the skin over a vein, usually on the inside of the elbow, with an antiseptic solution
- An elastic band (tourniquet) is placed around the upper arm to make the vein more visible
- A sterile needle is gently inserted into the vein, and a small amount of blood is drawn into a collection tube
- The needle is carefully removed, and light pressure is applied with cotton wool or a bandage to stop any minor bleeding
- The collection tube is labelled with your details and sent to the laboratory for analysis
Factors That Can Affect Accuracy
Certain factors may influence the reliability of your result:
- Starting a gluten-free diet before testing can reduce antibody levels and produce a falsely negative result
- IgA deficiency can affect the accuracy of IgA-based tests (this is precisely why the IgG version is used for such individuals)
- Immunosuppressant or steroid medications can lower antibody production
- Recent infections or serious illness may temporarily alter immune activity
Understanding Your Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test Results
Your results should always be reviewed alongside your symptoms, medical history, and other tests. The table below provides general reference ranges used in many laboratories.
| Parameter | Result Category | Range (U/mL) |
|---|---|---|
| tTG IgG | Negative | Less than 6.0 |
| tTG IgG | Weak Positive | 6.0 to 9.0 |
| tTG IgG | Positive | Greater than 9.0 |
Note: Some laboratories use a different threshold, where a result below 15 U/mL is negative and 15 U/mL or above is positive. Reference ranges vary between laboratories. Always refer to the values printed on your specific report.
Disclaimer: These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
Results During Special Conditions
Certain health conditions may affect how results are interpreted:
People with autoimmune conditions such as type 1 diabetes, Hashimoto's thyroiditis, autoimmune liver disease, psoriatic arthritis, rheumatoid arthritis, or heart failure may occasionally receive a positive tTG IgG result even without having coeliac disease. Similarly, individuals with liver cirrhosis may experience false positive results with some testing methods. Your doctor will review your full clinical picture before drawing any conclusions.
How to Maintain Healthy Levels
If your doctor has confirmed coeliac disease, the following general steps support better health:
- Follow a strict gluten-free diet as guided by your doctor and a registered dietitian.
- Attend regular follow-up appointments so that your antibody levels can be monitored over time.
- Read food labels carefully, as gluten can be present in many processed foods, sauces, and even some medicines.
Lupin Diagnostics Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test Price and Home Collection
The anti-tTG IgG test price starts at approximately ₹1,100, and home collection is available at your convenience through Lupin Diagnostics. The table below shows approximate prices across major Indian cities.
| City | Approximate Price (₹) |
|---|---|
| Mumbai | ₹1,300 |
| Bangalore | ₹1,300 |
| Chennai | ₹1,300 |
| Indore | ₹1,100 |
| Hyderabad | ₹1,300 |
| Kolkata | ₹1,300 |
| Pune | ₹1,300 |
| Bhopal | ₹1,100 |
Disclaimer: Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
You can book the tissue transglutaminase IgG test in your city using these simple steps:
- Select the test on the Lupin Diagnostics website
- Choose your city and preferred time slot
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre
- Receive your report via email or WhatsApp within the stipulated turnaround time
Home Collection
Looking for an 'anti-tTG IgG test near me'? Lupin Diagnostics offers convenient home sample collection across cities in India, allowing you to book the test without visiting a diagnostic centre. All samples are processed in NABL-accredited laboratories by trained professionals, and your digital report is usually shared via email or WhatsApp within one to three working days.
Frequently Asked Questions
The tTG IgA test is the standard first-line test for coeliac disease and works well for most people. However, individuals with IgA deficiency do not produce enough IgA antibodies, which can make the IgA test unreliable. In such cases, the tTG IgG antibody test is ordered, as these individuals may still produce IgG antibodies that indicate coeliac disease.
The anti-tTG IgG test is ordered primarily when a patient is suspected of having coeliac disease but also has an IgA deficiency. Since standard coeliac tests rely on IgA antibodies, they may miss the diagnosis in IgA-deficient individuals. The IgG version provides a more accurate result in this group.
No fasting is required. You can eat and drink as normal before sample collection. The key preparation step is to continue eating gluten-containing foods in the weeks before your test, as your doctor advises.
All blood-based tests for coeliac disease require a gluten-containing diet to produce accurate results. If you are already avoiding gluten, speak with your doctor about a supervised gluten challenge before proceeding with the tissue transglutaminase IgG test.
A positive result suggests that IgG antibodies against tissue transglutaminase are present in your blood, which is consistent with coeliac disease, particularly in individuals with IgA deficiency. However, a positive antibody test alone is not enough to confirm the diagnosis. Your doctor will typically recommend a small bowel biopsy to confirm.
IgG antibodies can take longer to normalise than IgA antibodies. Research suggests that after one year on a gluten-free diet, fewer than one in five IgA-deficient coeliac patients show normalised IgG anti-tTG levels. After two years, this rises to roughly one in three. Regular monitoring through repeat testing helps track progress.
Yes, a positive result does not always mean coeliac disease. Conditions such as type 1 diabetes, Crohn's disease, autoimmune liver disease, and liver cirrhosis have been associated with positive tissue transglutaminase antibody IgG test results. Your doctor will assess the full clinical picture before making a diagnosis.
Tissue Transglutaminase IgG Antibody (Anti-tTG IgG) Test
