Глиадин АТ IgМ

Anti-gliadin IgG (AGA-IgG) testing assesses immune reactivity to gliadin in the evaluation of suspected celiac disease (gluten enteropathy). The assay also supports follow-up of treated celiac disease by tracking antibody decline in response to a strict gluten-free diet and offers an objective measure of dietary adherence.

Anti-gliadin IgG represents IgG-class antibodies directed against gliadin, a prolamin component of gluten found in wheat, barley, rye, and oats. In genetically predisposed individuals, gluten exposure elicits an immune response with antibody deposition in the small-intestinal mucosa, leading to immune-mediated injury and mucosal atrophy. Resulting malabsorption may present with diarrhea, weight loss, anemia, and deficiencies of vitamins and micronutrients. Adherence to a strict gluten-free diet typically leads to clinical improvement, and detection of antigliadin antibodies serves as a serologic screening approach within this context. Compared with IgA-class antigliadin antibodies, anti-gliadin IgG generally shows lower analytic sensitivity and specificity. Laboratories frequently measure both IgA and IgG classes to increase the likelihood of detecting serologic evidence of gluten enteropathy. Anti-gliadin IgG is particularly informative when celiac disease coexists with selective IgA deficiency, which occurs in approximately 2–3% of affected individuals; therefore, concurrent measurement of total serum IgA is recommended. Serologic findings must be interpreted in conjunction with clinical features and other celiac markers: a positive result alone does not establish the diagnosis, and a negative result does not exclude it. With strict gluten withdrawal, anti-gliadin IgG titers typically decline, enabling use of this marker to monitor treatment response and gauge adherence to a gluten-free diet. For this reason, specimen collection is preferable before dietary modification. Celiac disease displays strong heritability, with a prevalence around 10% among close relatives compared with about 1% in the general population; relatives therefore warrant serologic evaluation that can include anti-gliadin IgG. Higher prevalence is also reported in type 1 diabetes mellitus, Hashimoto thyroiditis, Down syndrome, and systemic connective tissue diseases, and these groups are commonly included in targeted screening. Serology helps triage candidates for endoscopy and small-bowel biopsy, and some clinicians advocate a comprehensive serologic strategy that includes antigliadin (IgA and IgG), anti–tissue transglutaminase (IgA and IgG), and anti-endomysial antibodies. Anti-gliadin antibodies are not disease-specific. Anti-gliadin IgG may be observed in conditions such as irritable bowel syndrome, dyspepsia, primary biliary cirrhosis, autoimmune hepatitis, ulcerative colitis, Crohn disease, sarcoidosis, dermatitis herpetiformis, eczema, and bullous pemphigoid, which should be considered when interpreting results.