Search for
Tissue Transglutaminase IgA (TTG)
Immunity
Report in 4Hrs
At Home
No Fasting Required
Details
Detects IgA antibodies against tissue transglutaminase, an enzyme involved in the autoimmune response in celiac disease
₹399₹1,210
67% OFF
Tissue Transglutaminase IgA (TTG) - Comprehensive Medical Test Guide
- Section 1: Why is it done?
- Test Purpose: The TTG IgA test measures immunoglobulin A (IgA) antibodies against tissue transglutaminase, an enzyme found in the small intestine. These antibodies are produced by the immune system when it reacts to gluten in patients with celiac disease.
- Primary Indications: Screening for celiac disease in symptomatic patients • Investigating chronic gastrointestinal symptoms (diarrhea, abdominal pain, bloating) • Evaluation of malabsorption syndromes • Assessment of dermatitis herpetiformis (DH) • Screening family members of diagnosed celiac disease patients • Evaluation of unexplained iron deficiency or anemia • Investigation of failure to thrive in children • Assessment of osteoporosis risk factors
- Typical Timing and Circumstances: Performed when patients present with symptoms suggestive of celiac disease • Initial screening test in primary care settings • Before intestinal biopsy if TTG results are positive • As part of comprehensive autoimmune disease workup • In patients with unexplained nutritional deficiencies • When other autoimmune conditions are present (type 1 diabetes, thyroid disease) • During evaluation of chronic fatigue or neurological symptoms
- Section 2: Normal Range
- Reference Range Values: Negative/Normal: < 2.0 U/mL or < 1.0 U/mL (varies by laboratory) • Weak Positive: 2.0-10 U/mL • Positive: 10-100 U/mL • Strong Positive: > 100 U/mL
- Units of Measurement: U/mL (Units per milliliter) or Arbitrary Units (AU/mL) - reference ranges vary by laboratory assay used
- Result Interpretation: Negative Result: No detectable TTG IgA antibodies; celiac disease is unlikely but not completely ruled out • Weak/Borderline Positive: May indicate early celiac disease, gluten sensitivity, or false positive; further testing recommended • Positive Result: Suggests active celiac disease with high sensitivity (95-98%); intestinal biopsy typically recommended for confirmation • Strong Positive: Highly indicative of celiac disease; biopsy confirmation usually recommended before dietary changes
- What Normal vs. Abnormal Means: Normal: Immune system is not mounting an attack against tissue transglutaminase; celiac disease is unlikely • Abnormal: Indicates presence of anti-TTG IgA antibodies produced in response to gluten exposure; highly specific for celiac disease diagnosis
- Section 3: Interpretation
- Detailed Result Interpretation: Negative TTG IgA: Celiac disease very unlikely; patient does not have typical celiac disease • Weak Positive (2-10 U/mL): Consider repeat testing, evaluate IgG antibodies in IgA-deficient patients, may need intestinal biopsy • Moderate Positive (10-100 U/mL): Strong evidence of celiac disease; biopsy recommended • Strong Positive (>100 U/mL): Very high likelihood of celiac disease; intestinal changes almost certainly present
- What Different Results Indicate: Positive Results: Active celiac disease with intestinal immune response to gluten; patient should avoid gluten-containing foods • Negative Results with Symptoms: May indicate non-celiac gluten sensitivity, other gastrointestinal disorders, or very early disease; consider repeat testing or additional diagnostic workup • Results in Context: Must be interpreted with clinical symptoms, serum IgA levels, and intestinal biopsy findings
- Factors Affecting Results: Gluten Consumption: Test must be performed while patient is consuming gluten; false negatives occur on gluten-free diet • IgA Deficiency: 2-3% of celiac patients have total IgA deficiency; requires IgG antibody testing instead • Disease Activity: Antibody levels correlate with intestinal damage; may decrease with gluten avoidance • Assay Variation: Different laboratory methods may yield different cutoff values • Time from Symptom Onset: Very early disease may show negative results • Age: Antibody production may be lower in young children or elderly patients
- Clinical Significance of Result Patterns: TTG Positive + Endomysial Antibody (EMA) Positive: Confirms celiac disease with near 100% specificity • TTG Positive + EMA Negative: Unusual; may represent early disease or technical error; repeat testing recommended • TTG Negative + Clinical Symptoms: Consider non-celiac gluten sensitivity, repeat testing, or evaluate other conditions • Rising Antibody Titers: Indicates ongoing gluten exposure or inadequate dietary adherence • Falling Antibody Titers: Suggests good adherence to gluten-free diet and intestinal healing
- Section 4: Associated Organs
- Primary Organ System Involved: Small Intestine (Primary): Duodenum and jejunum are primary sites of gluten-induced immune damage • Immune System: Adaptive and innate immune response in gut mucosa • Associated Secondary Systems: Gastrointestinal tract, bone metabolism, nervous system, reproductive system
- Medical Conditions Associated with Abnormal Results: Celiac Disease: Autoimmune disorder causing intestinal mucosal damage • Dermatitis Herpetiformis: Skin manifestation of celiac disease with GI involvement • Refractory Celiac Disease: Persistent symptoms despite strict gluten-free diet • Non-Celiac Gluten Sensitivity: May show positive TTG in some cases • Gastrointestinal Dysfunction: Malabsorption, nutrient deficiencies
- Diseases This Test Helps Diagnose or Monitor: Celiac Disease: Primary diagnosis; test has 95-98% sensitivity in patients on gluten-containing diet • Associated Autoimmune Conditions: Type 1 diabetes, thyroid disease, Sjögren's syndrome • Malabsorption Syndromes: Iron deficiency anemia, vitamin B12 deficiency, folate deficiency • Dermatitis Herpetiformis: Gluten-dependent skin disease with intestinal pathology • Monitoring Response to Gluten-Free Diet: Serial testing tracks intestinal healing and immune response
- Potential Complications Associated with Abnormal Results: Intestinal Complications: Villous atrophy, malabsorption, increased intestinal permeability • Nutritional Deficiencies: Iron, vitamin B12, folate, calcium, vitamin D deficiency • Bone Health: Osteoporosis and increased fracture risk from malabsorption • Neurological: Ataxia, peripheral neuropathy, seizures in some patients • Reproductive: Infertility, miscarriage, adverse pregnancy outcomes if untreated • Increased Malignancy Risk: Intestinal lymphoma if celiac disease untreated for extended periods • Associated Autoimmune Conditions: Higher risk of developing other autoimmune diseases
- Section 5: Follow-up Tests
- Additional Tests Recommended Based on Results: If TTG IgA Positive: Endomysial Antibody (EMA) test for confirmatory specificity • If TTG IgA Negative with High Clinical Suspicion: Total serum IgA level to rule out IgA deficiency; if deficient, test TTG IgG and EMA IgG • If TTG IgA Positive: Tissue transglutaminase IgG if patient has selective IgA deficiency • For All Cases: Human leukocyte antigen (HLA-DQ2/DQ8) testing if serological results uncertain
- Further Investigations if Positive: Upper Endoscopy with Duodenal Biopsy: Gold standard for confirming celiac disease diagnosis • Intestinal Biopsy: Demonstrates villous atrophy, crypt hyperplasia, and intraepithelial lymphocytes • Complete Blood Count: Assess for anemia from malabsorption • Iron Studies: Serum iron, ferritin, total iron-binding capacity • Vitamin B12 and Folate Levels: Evaluate for nutritional deficiencies • Tissue Transglutaminase IgG: In IgA-deficient patients • Anti-Endomysial Antibody IgG: In IgA-deficient patients
- Monitoring Frequency for Ongoing Conditions: Initial Diagnosis: TTG and EMA testing at time of diagnosis • After Starting Gluten-Free Diet: Repeat TTG IgA at 6-12 months to assess dietary adherence and intestinal healing • Annual Monitoring: Yearly TTG testing in first 1-2 years to confirm sustained remission • Long-term Follow-up: Every 1-2 years or if new symptoms develop • If Antibodies Remain Elevated: Repeat testing at 6 months; consider patient education on gluten avoidance • When Symptoms Persist on Gluten-Free Diet: Retest TTG IgA; investigate refractory disease or other conditions
- Related Tests Providing Complementary Information: Endomysial Antibody (EMA): Higher specificity (98-100%) but lower sensitivity than TTG • Deamidated Gliadin Peptide (DGP) IgA and IgG: Alternative serological markers • Total Serum IgA: Necessary to interpret TTG results; helps identify IgA deficiency • HLA-DQ2 and HLA-DQ8: Genetic markers; present in >99% of celiac patients • Thyroid Peroxidase (TPO) Antibodies: Screen for associated thyroid disease • Tissue Transglutaminase IgG: Used when total IgA is deficient • Anti-Endomysial Antibody IgG: Confirmatory test in IgA-deficient patients
- Section 6: Fasting Required?
- Fasting Requirement: No - Fasting is NOT required for this test
- Patient Preparation Requirements: General Preparation: Standard venipuncture; no special preparation needed • Patient can eat and drink normally before test • No restrictions on daily activities before blood draw • Comfortable, loose-fitting clothing recommended for easy blood draw access
- Critical: Gluten Consumption Before Testing: IMPORTANT: Patient should be consuming gluten-containing foods for accurate results • Test should be performed BEFORE starting a gluten-free diet • If patient has already started gluten-free diet, false negative results are likely • Patient may need to reintroduce gluten (2 slices of bread daily) for 4-6 weeks before testing if on gluten-free diet • Discuss timing with healthcare provider to ensure proper test interpretation
- Medications to Avoid: No medications need to be stopped or avoided for this test • Immunosuppressive medications may theoretically affect antibody levels but should not be discontinued without medical guidance • All current medications should be continued as prescribed • Inform healthcare provider of all medications being taken, especially immunosuppressants or biologics
- Special Instructions: Collection Method: Simple blood draw via venipuncture into serum separator tube • Timing: Can be performed at any time of day • Sample Handling: Serum is separated from blood cells and tested • Results Timing: Typically available within 1-3 business days depending on laboratory • Patient Information: Bring valid identification and insurance information to laboratory
How our test process works!
