Traditionally, food allergies have been associated with an itchy rash after eating certain foods. And few people know that recurrent diseases of the skin, digestive and even respiratory systems can also be the result of a food reaction. The “correct” diagnosis in such cases is often belated. And to confirm or refute the guess is possible only by laboratory means.
Why does food allergy occur?
Maintaining the constancy of the internal environment is one of the basic “needs” of the body, and immunity plays one of the leading roles here. Any foreign objects in the body are bound, destroyed and excreted. And, normally, these processes occur naturally and imperceptibly “for the eyes.” However, in some cases, the reactions become systemic, accompanied by well-known symptoms.
Allergies, like inflammation, are, in fact, a normal defense reaction of the body, but the causes of its occurrence are not the norm.
In the case of a food allergy, the reaction may be due to:
violation of the normal splitting of food (gastritis, enteritis, pathology of the liver, gallbladder and pancreas),
damage to the natural intestinal “barrier” (chronic diseases of the small intestine),
“Overdose” of chemicals in food,
hereditary hypersensitivity to certain antigens,
genetic characteristics of immunity (hyperreactivity),
cross-react with certain pollen allergens.
Insufficiently digested food elements, as well as an abundance of chemical preservatives and dyes “overload” the local immune system, provoking the activation of systemic defense mechanisms. And the genetic predisposition to hyperreactivity only enhances the reaction.
In this case, class E antibodies enter the bloodstream, under the influence of which, in fact, a typical allergic process develops in the skin and mucous membranes. The symptoms and effects of which range from mild itching to severe anaphylaxis.
What to look for
“In favor” of an undiagnosed allergic reaction say:
skin pathology – excessive dryness, cracks, peeling, poor healing, frequent pustular diseases;
digestive pathology – stool disorders, nausea, abdominal bubbling, increased gas production, pain;
respiratory system pathology – cough, shortness of breath.
It must be said that respiratory symptoms in food allergies are rare and are largely associated with cross-reactions between food and pollen allergens.
How to check for allergies
You can confirm or deny the allergic nature of the symptoms using:
a general blood test with a leukocyte formula, where an increase in eosinophils serves as a marker of allergy;
blood test for IgE total and eosinophilic cationic protein, increasing in allergies tens and hundreds of times.
In most cases, these tests are enough to make a diagnosis, and the next step is to directly search for the allergen:
blood test for IgE to the “suspected” allergen
or to a group of allergens in the panel.
The second option is more often used to cover several or the most common allergens at once, as well as in the case when a polyvalent (multifactorial) allergy is assumed or it is not possible to narrow the “search circle” in any way.
For example, “RIDA-screen No. 3 food allergy complex” includes 20 most allergenic food products, including nuts, seafood, vegetables, fruits, meat, milk and eggs. And the result is calculated for each allergen from the panel.
And the panels of food allergens https://en.wikipedia.org/wiki/Allergen according to the Immulite method include the determination of IgE immediately to 4-6 allergens of only a certain group (meat, vegetables, cereals and others) and assume the total result for the entire panel.