Tissue Transglutaminase Antibody - IgA
What is tTG IgA?
Tissue Transglutaminase Antibody - IgA test is also known as Celiac disease antibody test or tTG. This test is done to detect celiac disease and also to determine the efficacy of a gluten-free diet.
Why is tTG IgA done?
The tissue transglutaminase antibody - IgA test is done:
In case of symptoms of celiac disease such as chronic diarrhea, bloating, pain in the abdomen, anemia, and weight loss
If an infant is irritable for a long time
If an infant is not growing at a normal rate
In case of a family history of celiac disease
In patients undergoing treatment for celiac disease
What does tTG IgA Measure?
The tissue transglutaminase antibody - IgA test measures self-generated antibodies present in the blood which are produced by the body in response to autoimmune disorders such as celiac disease and other gluten-sensitive conditions. In celiac disease, an inappropriate immune response is generated to counter the presence of gluten. Gluten is a protein which is found in wheat, rye, and barley.
Due to the immune response produced by the body, there is inflammation of the small intestine which leads to damage and destruction of the villi that lines the walls of the intestine. Villi are finger-like structures present in the small intestine. These are responsible for increasing the surface area of the intestine and help in digestion of food. They allow various nutrients, vitamins, minerals, electrolytes, and fluids to be absorbed into the body.
If a person suffering from celiac disease get exposed to gluten content, the body in response starts producing antibodies. These antibodies cause inflammation which damages the villi. This damage will further impact the body’s ability to absorb food. In such conditions, the body begins to develop signs and symptoms which are associated with malnutrition and malabsorption.
Interpreting tTG IgA results
Result (In Units)
Reference range may vary from lab to lab*
A positive anti-tissue transglutaminase antibody IgA test usually indicates celiac disease
A negative test usually means that symptoms are not likely due to celiac disease. If the person being tested has not consumed any gluten for several weeks or months prior to the test, then the test may show false-negative results
All antibody tests for celiac disease are usually followed by an intestinal biopsy which is the gold standard for diagnosis of this condition