Смесь пищевых аллергенов fx20 (ImmunoCAP), IgE: пшеница, рожь, ячмень, рис

The ImmunoCAP food allergen mix fx20 (wheat, rye, barley, rice) measures allergen‑specific IgE to a cereal grain mixture to assess IgE‑mediated food sensitization in children and adults, including those younger than 3 years. Results help attribute flares of atopic disease—such as dermatitis, urticaria, angioedema, gastrointestinal reactions, anaphylaxis, rhinitis, or asthma—to this grain group and guide whether to order individual specific IgE tests for wheat, rye, barley, or rice.

An allergen is a substance that provokes an allergic response. In atopic disease, exposure to specific allergens induces IgE production and can trigger type I (immediate, IgE‑mediated) hypersensitivity. Demonstrating allergen‑specific IgE in serum supports sensitization to that allergen and helps identify the likely trigger, informing both management and prevention strategies. Food allergy reflects immune‑mediated mechanisms and should be distinguished from food intolerance, which arises from non‑immune causes such as food composition, preparation, gastrointestinal disorders, or metabolic defects. Cereal grains can cause both true food allergy and non‑IgE‑mediated intolerance (gluten enteropathy/celiac disease). Allergenic proteins vary in solubility and stability to heat and digestion; processing may diminish or, in some cases, enhance allergenicity. Most food allergy occurs in early childhood, particularly before 3 years of age. Approximately 90% of reactions involve milk, egg, fish and shellfish, soy, wheat, peanuts, and tree nuts. Among grain proteins, gluten (including gliadin) from wheat and rye, hordein from barley, avenin from oats, zein from corn, and Ory s 1 from rice are well‑described allergens. Barley also contains gluten; barley flour is used in porridges, baking mixes, cereal bars, and cookies, and barley malt is present in beer and some baked goods. Cross‑reactivity occurs among related grasses (e.g., wheat, rye, barley, oats). Rye is a frequent sensitizer; characterized rye allergens include Secc1 (trypsin/amylase inhibitor), Secc12 (profilin), Secc20 (secalin), and gliadin, with reported cross‑reactivity to wheat, barley, oats, and rice. In patients allergic to rye, co‑sensitization with nuts, poppy seed, sesame, soy, or kiwi is not uncommon. Clinical manifestations related to these grains involve the gastrointestinal tract (cheilitis, gastritis, colitis, gastroenteritis, irritable bowel syndrome), skin (atopic dermatitis, urticaria, angioedema), and, less often, the respiratory system (allergic rhinitis, bronchial asthma). Wheat is a potent allergen; intolerance to wheat groats or semolina may appear in both children and adults, often after repeated exposures. In infants, reactions may emerge during the introduction of complementary foods. Contributing factors can include feeding practices, starch content, genetic predisposition, immune status, concurrent disease, and enzyme deficiency. Wheat is ubiquitous (flour, starch, bran, baked goods, pasta, confections, beer), and its allergenicity relates largely to grain proteins (gluten proteins, albumins, globulins). Immune responses to wheat gluten may also underlie celiac disease. Rice does not contain gluten and is widely used in individuals who avoid gluten; however, it harbors more than 10 proteins capable of provoking true IgE‑mediated allergy, sometimes with reactions to very small amounts. Marked reactions are reported in adults and children; up to 5% of infants may not tolerate rice porridge, and exposure can occur via breast milk when ingested by a lactating mother. This assay quantifies specific IgE to wheat, rye, barley, and rice using an ImmunoCAP solid‑phase immunofluorescent method with high analytical sensitivity and specificity, recognized by the World Health Organization and the World Allergy Organization as a "gold standard" for in vitro allergy testing.