Allergic reactions

In response to the introduction of allergens into the body and develop allergic reactions, which can be specific and nonspecific. The specific reaction is preceded by the

latent period, when the hypersensitivity to the allergen first introduced into the body develops, the so-called sensitization. This occurs as a result of the development of antibodies - protein substances that are formed in response to the introduction of only this allergen, or the appearance of lymphocytes capable of interacting with

with this allergen. If by the time of their appearance the allergen is removed from the body, no painful manifestations are noted. With the repeated exposure of the allergen to an already sensitized organism, an allergic reaction develops-the interaction of antibodies or lymphocytes with the allergen that caused them. As a result, a number of biochemical processes occur with the release of chemical substances( histamine, serotonin, etc.), damaging cells, tissues and organs, which is the basis of allergic diseases. The increased sensitivity of the organism in such cases is specific, i.e.it manifests itself in relation to the allergen, which previously caused a state of sensitization.

Nonspecific allergic reactions occur during initial contact with the

allergen without previous sensitization. The allergen that enters the body causes the formation of substances that damage cells, tissues and organs. Among these reactions is idiosyncrasy - intolerance of certain foods and medicinal substances.

In most cases, a person develops specific allergic reactions. By the time of manifestation of allergic reactions, it is customary to divide into two types-instant and delayed. Reactions of immediate type are considered skin and systemic

allergic reactions( respiratory, digestive and other systems) that occur through 15 - 20 min after exposure to a specific allergen. They manifest themselves in the skin blister, spasm of the bronchi, disorders of the gastrointestinal function, etc. Allergic reactions of the immediate type include anaphylactic shock, serum sickness, hay fever, urticaria, bronchial asthma, and Quincke's edema. Serum sickness in non-sensitized

people develops 2 to 12 days after the introduction of serum or?- Globulin, and with the repeated administration of serum - much earlier. It is characterized by the appearance of a rash with excruciating itching, swelling of lymph nodes, fever and other symptoms. Quincke edema - transient limited

swelling of the skin, subcutaneous tissue and mucous membranes - can develop if any allergen gets into the body;more often on the face, larynx, gastrointestinal tract. There are also cases of non-allergic - hereditary - Quincke's edema. Slower-type reactions develop for hours and sometimes days. These include hypersensitivity to bacteria( for example, tuberculosis, brucellosis, sapa, tularemia, etc.), contact dermatitis among workers in the chemical industry, pharmacists, medical staff.

Allergy does not develop in all cases of body contact with allergens. A certain role is played by heredity, the state of the nervous and endocrine systems. If both parents, for example, have pollinosis, anaphylaxis, an atonic( hereditary) form of bronchial asthma, some forms of an allergic rhinitis, in children allergic diseases develop in more than 70% of cases;in families where only one of the parents is sick, up to 50% of children become ill.

Not the diseases themselves are transmitted by the parents, but the predisposition to them is an increased ability to respond with an allergic reaction to the action of exogenous allergens. Therefore, depending on the type of allergen and the ways of its receipt

in the body, the allergic disease in the child can manifest itself in any form. To the development of allergies predispose to violations of the nervous and endocrine systems, as well as brain trauma, negative emotions, decreased adrenal function.