Is tTG IgA useful for allergy?

tTG IgA (anti-tissue transglutaminase IgA) is a highly specific and sensitive serological marker for celiac disease, an autoimmune condition triggered by gluten ingestion. It is not useful for diagnosing allergies, which are typically IgE-mediated hypersensitivity reactions. Celiac disease involves a different immune pathway (IgA and T-cell mediated) leading to intestinal damage, whereas allergies involve mast cell degranulation via IgE. Using tTG IgA to test for food allergies would be inappropriate and could lead to misdiagnosis. If you suspect a wheat allergy, specific IgE testing or skin prick testing is indicated. If you suspect gluten-related disorders, tTG IgA is the first-line screening test for celiac disease, but it does not detect non-celiac gluten sensitivity. The test must be performed while the patient is on a gluten-containing diet, and positive results usually require confirmation by intestinal biopsy. The evidence for tTG IgA in celiac disease screening is strong, supported by numerous clinical studies and international guidelines. However, this information is not derived from the provided context, which did not cover celiac disease or allergy testing. Consumers considering such tests should consult a healthcare professional for proper interpretation and to avoid unnecessary dietary restrictions.