Gliadin (Deamidated) Antibody (IgA) - This test checks for antibodies against gliadin, a key protein in gluten, to help diagnose celiac disease. While gliadin antibodies can appear in people without celiac disease, making the test less specific, recent advancements have improved its accuracy. The test now uses deamidated gliadin peptides, which have a higher chance of detecting celiac disease accurately due to their strong reaction with celiac-specific antibodies.