9168. Gliadin, IgA antibodies

Celiac disease is an autoimmune disease involving damage to the epithelium of the small intestine as a result of the immune system’s response to dietary gluten (a protein found in cereals). It may cause diarrhea, weight loss, steatorrhea, iron-deficiency anemia, skin rash, drowsiness, and bloating.

Gliadins are a group of alcohol-soluble proteins that are components of gluten in cereal grains, particularly wheat, barley, rye, and oats.

Antibodies to gliadin (AGA) may be detected in adults and children with celiac disease, as well as in individuals with gluten-sensitive enteropathies such as dermatitis herpetiformis. However, IgA AGA antibodies may also occur in other intestinal diseases, including Crohn’s disease and ulcerative colitis, as well as in children without celiac disease. This test is particularly useful when gluten-sensitive enteropathy is associated with selective IgA deficiency, which is observed in 2–3% of cases of celiac disease.

Gluten-sensitive enteropathy is a multifactorial disease with a strong genetic predisposition. Its prevalence among close relatives of patients with celiac disease is 10%, which is significantly higher than in the general population (≈1%). Gluten is found in the grains of wheat, rye, barley, oats, and certain other cereals.

One of the components of gluten – gliadin – can trigger an immune response, accompanied by the production of specific antigliadin antibodies, which initiate an inflammatory reaction and lead to atrophy of the small intestinal mucosa.

Determination of antigliadin antibodies is an important tool for screening first-degree relatives of patients with celiac disease and individuals with associated conditions such as type 1 diabetes mellitus, Hashimoto’s autoimmune thyroiditis, Down syndrome, and systemic connective tissue diseases, with the aim of early detection of the disease.

IgA antibodies to gliadin are more specific for celiac disease than IgG antibodies; therefore, combined screening for AGA IgA and IgG is most effective in cases of total IgA deficiency associated with celiac disease.

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

• Venous blood

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