The tissue transglutaminase (tTG) IgA test is done as a part of assessment of certain autoimmune conditions, most particularly celiac disease. This test is done to diagnose celiac disease and to assess the effectiveness of a gluten-free diet. Detecting celiac disease where body produces two antibodies that attack tTG, can be effectively done by measuring the IgA form of tTG antibody available in the blood. This way is very useful as it is made in the small intestine where inflammation and irritation are caused in sensitive people by gluten. This test is in general suggested to people showing symptoms of celiac disease, that includes anemia and abdominal pain.
Prior to test, sometimes from way as long as a week or more as suggested by your doctor have food that is rich in gluten like breads, pastas and baked goods, as body will produce respective antibodies only when exposed to gluten. In case if gluten is ceased from the diet being taken there won’t be any antibody response that is to be measured. Things turn easier for both the patient and the lab technician if the clothing worn is like T-shirt or short-sleeved shirt giving easy access to the parts where blood is to be squeezed.
The Anti tTG IgA test results can be either positive or negative. A positive test result means a presumptive celiac disease. All positive tests are followed by an intestinal biopsy, which is used for a definitive diagnosis of celiac disease. A negative result means that the pre observed symptoms not likely due to celiac disease.
A health professional or a lab technician will draw the blood from a vein in hand. For an infant, the blood is drawn from heel by making a puncture with a small needle called lancet and the blood is then collected into the vial. In cases where blood is drawn from a vein, the skin surface is cleaned with antiseptic and a tourniquet is placed around the upper arm or in rare cases some good enough pressure is applied manually for the veins to get swollen with blood. A needle is then inserted into a vein and enough blood to test is withdrawn and collected in a vial or syringe.