ANTI HUMAN TISSUE TRANSGLUTAMINASE (TTG) ANTIBODY (IGG)

The Anti-Human Tissue Transglutaminase (tTG) Antibody (IgG) Test is a specialized blood test that detects Immunoglobulin G (IgG) antibodies against tissue transglutaminase (tTG), an enzyme present in many body tissues. This test is primarily used to help diagnose celiac disease, particularly in individuals with selective IgA deficiency, where the standard Anti-tTG IgA test may produce false-negative results.

Celiac disease is an autoimmune disorder triggered by the ingestion of gluten, a protein found in wheat, barley, and rye. In affected individuals, gluten consumption stimulates an immune response that damages the lining of the small intestine, resulting in inflammation, poor nutrient absorption, and various gastrointestinal and systemic symptoms.

Although the Anti-tTG IgA test is the preferred first-line screening test for celiac disease, the Anti-tTG IgG test plays an important role in evaluating patients with low or absent IgA levels and in selected clinical situations. It is often performed alongside Total Serum IgA, Deamidated Gliadin Peptide (DGP) antibodies, and Endomysial Antibody (EMA) tests to improve diagnostic accuracy.

The Anti-Human Tissue Transglutaminase (tTG) IgG Test helps healthcare providers diagnose gluten-related autoimmune disorders and guide appropriate treatment, including the initiation and monitoring of a gluten-free diet.

Benefits of the Test

• Detects Anti-tTG IgG antibodies with high accuracy
• Supports diagnosis of celiac disease
• Particularly useful in patients with selective IgA deficiency
• Helps evaluate gluten-related autoimmune disorders
• Assists in identifying malabsorption disorders
• Supports monitoring of gluten-free diet response
• Requires only a blood sample

Why Doctors Recommend This Test

Doctors may recommend this test for individuals with:

• Chronic diarrhea
• Persistent abdominal bloating
• Unexplained weight loss
• Iron deficiency anemia
• Chronic fatigue
• Malabsorption syndrome
• Selective IgA deficiency
• Family history of celiac disease
• Autoimmune disorders
• Suspected gluten-related illness

Preparation Before Test

Sample Required

• Peripheral venous blood sample (Serum)

Preparation Guidelines

• No fasting is required.
• Continue eating gluten-containing foods before testing unless your physician advises otherwise. Eliminating gluten before the test may reduce antibody levels and affect diagnostic accuracy.
• Inform your healthcare provider about any autoimmune disorders or current medications.
• Follow laboratory instructions before sample collection.

Reporting Time

Results are generally available within 3–7 working days, depending on laboratory processing.

Who Should Take This Test?

This test is recommended for:

• Individuals with symptoms suggestive of celiac disease
• Patients with selective IgA deficiency
• Children and adults undergoing celiac disease evaluation
• Individuals with chronic digestive symptoms
• Patients with unexplained nutritional deficiencies
• Individuals with autoimmune disorders associated with celiac disease
• Patients requiring additional confirmation of gluten-related disorders

Clinical Significance

Elevated Anti-Human Tissue Transglutaminase (tTG) IgG antibodies may indicate:

• Celiac Disease
• Gluten-Sensitive Enteropathy
• Gluten-Related Autoimmune Disorders
• Malabsorption Syndrome

Common symptoms may include:

• Chronic diarrhea
• Abdominal pain
• Abdominal bloating
• Weight loss
• Fatigue
• Iron deficiency anemia
• Nutritional deficiencies
• Delayed growth in children
• Recurrent mouth ulcers

A positive Anti-tTG IgG result supports the diagnosis of celiac disease, particularly in individuals with IgA deficiency. Results should always be interpreted alongside clinical findings, Total Serum IgA, Anti-tTG IgA, DGP antibodies, EMA antibodies, and, when appropriate, an intestinal biopsy.