9325. Deamidated gliadin peptides, IgA antibodies

Celiac disease is an autoimmune disorder that damages the epithelium of the small intestine as a result of the immune system’s response to dietary gluten (a protein found in cereals).

Symptoms of the disease:

• diarrhea;
• weight loss;
• fatty stools;
• iron-deficiency anemia;
• skin rash;
• drowsiness;
• flatulence.

This is a sensitive test for diagnosing celiac disease when symptoms are present, particularly in children under 2 years of age, and for monitoring a gluten-free diet. The test may be ordered as part of a panel including total IgA, IgA antibodies to tissue transglutaminase, and IgA antibodies to endomysium.

Gluten is a collective term for various cereal proteins: wheat glutenins, barley hordeins, and rye secalins. The most toxic fragment of the gluten molecule is its alcohol-soluble fraction – gliadin. After absorption through the gastrointestinal mucosa, gliadin is deamidated by tissue transglutaminase, resulting in the formation of new antigenic epitopes – deamidated gliadin peptides, which are much more specific for celiac disease than native gliadin peptides.

In patients with a genetic predisposition to celiac disease, gliadin peptide fragments bind to HLA-DQ2/DQ8 molecules on the surface of antigen-presenting cells, allowing T helper cells to recognize the antigen more effectively. This triggers an autoimmune response, leading to pathological changes in the tissues, with changes in the mucosa of the small intestine being particularly pronounced. The sensitivity of the 'IgA + IgG antibodies to deamidated gliadin peptides' test is 98.3-100%, and its specificity is 96.3-98.8%.

• Screening of patients with suspected celiac disease (with typical and atypical clinical presentations) and individuals at increased risk of developing the disease.
• Monitoring the effectiveness of treatment with a gluten-free diet.

• Venous blood

In order to exclude factors that may affect the test results, we recommend to follow the preparation rules: