Allergens: types, causes in adults and how they are tested

Allergens are harmless substances that are perceived by the cells of the immune system as potentially harmful. The response to these elements causes painful symptoms in people and often leads to more serious consequences than the body's fight against pathogenic microflora. This immunopathological reaction is called allergy.

What are allergens

The structure of allergens does not contain any compounds hazardous to the body. For a healthy person, such substances are completely safe.

However, if he has disorders in the immune system, then various elements of the surrounding world, getting into the body, can cause sensitization, as a result of which the immune system produces antibodies to these substances, perceiving them as malicious.

Allergens can be animal hair, insect bites, chemicals, metals, smoke, pollen plants, food, medicines, mold spores, dust, that is, everything that a person comes into contact with daily.

Normally, immunity is tolerant to such elements, without showing a purposeful action to them. In a person prone to sensitization, when a substance enters the body for the first time, they begin antibodies are produced, which, when re-penetration of allergens, attack them as foreign and dangerous agents.

Why the body begins to perceive these substances aggressively is still not known. It is believed that various factors contribute to this: heredity, stress, poor ecology, frequent infectious diseases, and others. Various pathologies in the body, merging together, are capable of provoking an immunopathological process.

In the process of allergy formation, there are three stages. The moment the antigen (allergen) meets the cells of the immune system is called the immunopathological stage. During this period, antibodies are created that can affect the antigen. At the pathochemical stage, the immune complexes are deposited on special cells containing inflammatory mediators. The third stage - pathophysiological - is characterized by a direct allergic reaction of the body, manifested by sneezing, urticaria, runny nose, angioedema and others symptoms.

The list of allergens is huge, so they are divided into various groups that are similar in certain ways:

• Food allergens. The immunopathological process can be provoked by ordinary food. Allergens of animal origin include eggs, seafood, milk and other foods, plant allergens - citrus fruits, wheat, nuts, etc. Particular attention should be paid to products that have chemical additives - dyes, flavors, which exhibit high sensitizing properties.
• Pollen allergens. Almost half of the plants on the planet produce pollen that can trigger the body's immunological response. Since this allergy is very common, it is the most studied of all. Pollen allergens provoke sensitization only during the flowering period. Thus, this allergy is seasonal, for example, one person has hives and a runny nose in the spring, and another in August. Allergy to pollen and food is often cross-cutting, that is, if there is a pathological reaction to the flowering of any grass, then it can also occur to plant products.
• Epidermal allergens. These allergens are elements of the animal kingdom. These include the hair of cats, dogs, feathers and down of birds, especially chickens or ducks, epidermis or human hair. Together with these substances, mites of microscopic size often penetrate into the body, which also have high sensitizing properties.
• Household allergens. Most often, such an allergen is dust, which contains particles of wood, fabrics, paper and other elements. House dust contains spores of mold fungi, micro-mites, particles of skin and wool, that is, what in itself are allergens.
• Helminth allergens. Acute allergic reactions can cause waste products of helminths - parasites that live in the human intestine.
• Infectious agents. Some pathogenic organisms can provoke an allergic reaction. Sensitization is caused by streptococci and pathogenic fungi. Particularly dangerous is hemolytic streptococcus, which in structure is similar to some human organs. As a result of the production of antibodies to it, autoallergy develops, in which one's own organs are attacked.
• Medicinal allergens. An allergy can occur to any drug, vaccine or serum. Antibodies are often produced against antibiotics, albumin, or radiopaque contrast agents.

Causes of allergies in adults and children

There are many reasons due to which the development of the immunopathological process becomes possible. Allergies are hereditary or acquired. In adults and children, provoking factors may differ, since anthropogenic factors are more characteristic of older people.

However, most experts note that the main reason for the pathological enhancement of immunological protection is the failure of the body's cleansing system. In the first place is the gastrointestinal tract, in the second - the liver and kidneys.

The causes of allergies in adults are often accompanied by malnutrition and diseases of the gastrointestinal tract. If there are pathologies in the digestive system, for example, peptic ulcer or dysbiosis, then the walls intestines become more permeable, and through them large molecules of various substances. The immune system begins to perceive them as foreign, and to produce the corresponding antibodies.

A person daily consumes foods that can become allergens. If it transmits, there are parasites in the intestines, and the organ itself is inflamed, then the risk of developing allergies increases significantly. Malfunctions of the liver and kidneys lead to the accumulation of decay products and toxins in the body, thus increasing the likelihood of an allergic reaction.

Another cause of allergies that develops in both adults and children is heredity. If one of the parents suffers from allergic reactions, then the risk of developing pathology in the child increases. In the case when the allergy is diagnosed in both the mother and the father, the child will suffer from this disease with a probability of up to 80%.

Other causes of allergies in adults:

• Professional activity. If a person often and for a long time comes into contact with potentially hazardous substances (metals, chemical solutions, medicines, etc.), then after a while the risk of developing allergies is significant increases.
• Use of cosmetics and household chemicals. Low-quality cosmetics, powders or dishwashing detergents, floors often contain harsh chemicals that, if penetrated under the skin, can cause severe allergic reactions.
• Bad habits. Alcoholic beverages increase the intoxication of the body and disrupt the functioning of the liver, and tobacco smoke damages the mucous membranes of the respiratory tract. All this contributes to the penetration and accumulation of allergens in the body.
• Infections. Chronic respiratory infections: sinusitis, laryngitis, tonsillitis and others lead to bacteria that cause allergies are constantly present in the body, and, therefore, increase the risk of developing immunopathological process.

Causes of allergic reactions in children

In infants, allergies often develop against the background of the mother's refusal to breastfeed and early artificial feeding. The baby has not yet had time to form the immune system, and any product can cause specific allergic reactions.

Allergies in children can also occur due to the mother's non-compliance with the diet during pregnancy. Pregnant women are advised to refrain from foods that are strong allergens, smoking and drinking alcohol. If she does not adhere to the rules, then the propensity for allergies in the child can form even in the prenatal period.

Blood tests for allergens and skin tests

In order to properly treat allergies, it is necessary to be examined by an allergist and be tested for allergens. Depending on the provoking factor and the severity of the pathology, the doctor prescribes the appropriate treatment. You can detect allergies in yourself if you carefully study its symptoms.

The main symptoms of allergies:

• respiratory manifestations in the form of sneezing, runny nose, coughing, wheezing, asthma attacks;
• dermatosis is manifested by hyperemia and swelling of the skin, itching, rashes, peeling;
• conjunctivitis is characterized by lacrimation, burning and pain in the eyes;
• enteropathy is characterized by swelling of the tongue, lips, nausea and diarrhea;
• anaphylactic shock develops against the background of convulsions, shortness of breath, vomiting, dizziness, loss of consciousness.

Diagnostics

To make a correct diagnosis, the patient needs to pass one of the tests - a skin test or a blood test for allergens. Diagnostic measures to identify the allergen are carried out in clinics with an allergology department.

Skin tests are performed by scarification, injection or application methods. In the first method, substances that are presumably allergens are applied to the hand, then small incisions are made in these places, and the reaction is monitored. If the skin is red and inflamed, then the test is considered positive.

Applications differ in the duration of the test, it is carried out for two days. The skin is not damaged when allergens are applied, the strip with substances is attached to the wrist with a plaster. When provoked, a small amount of an allergen is injected under the skin.

Blood analysis allergens are made in laboratories with modern equipment. The cost of tests will be somewhat more expensive than skin tests, but the result of such a study is more accurate.

Special preparation for taking a blood test for allergens is not required. For examination, venous blood is taken from the patient. It is passed through a centrifuge and the serum is recovered. Then the material is placed in test tubes with potentially irritating substances. If the patient has antibodies - immunoglobulin E (Ige) to them, then this can be seen in the test results.

Allergen analysis is carried out in two ways. In a radioallergosorbent test, radioactive isotopes are added to the test tube. Then, with the help of a special device, the results are revealed. If a multiple allergen-sorbent test is performed, then a fluorescent dye is added to the tubes. The result can be seen in the photo by the glow.