A blood test called the tissue transglutaminase IgA (tTG-IgA) test is used to identify celiac disease. An immune-mediated inflammatory process that harms the small intestine causes celiac disease. Consuming gluten in your diet can cause this condition. If you experience symptoms of celiac disease, such as abdominal pain, diarrhoea, or weight loss, or if you have a family history of the condition, a tTG-IgA test is indicated. In some circumstances, it is also done to evaluate the effectiveness of the celiac disease treatment. For both adults and children older than 3 years, this test has the highest sensitivity for the detection of celiac disease