Chapter 3 Skin Types To properly care for your skin and understand all its desires, you need to know exactly what type of skin it belongs to. Knowing your type, you will not harm your skin with completely inappropriate cosmetics. Using necessary funds your care will be the best,

Chapter 3. CLINICAL PICTURE OF ICP AS A COMPLEX OF SPECIFIC RESPONSE REACTIONS TO NON-SPECIFIC IRRITIVES The clinical picture in cerebral palsy can also be considered as a complex of specific responses of effectors to an intense non-specific stimulus. Here

Chapter 4 Basic principles of diagnosis of allergic diseases What are the features of the diagnosis of allergic diseases? First, it is necessary to establish the allergic or non-allergic nature this disease. Sometimes this task is not difficult

Types of allergic reactions Depending on the time of occurrence, all allergic reactions can be divided into 2 large groups: if allergic reactions between the allergen and body tissues occur immediately, then they are called immediate type reactions, and

I type of allergic reactions The first type includes allergic reactions (hypersensitivity) of the immediate type. They are called atopic. Allergic reactions of immediate type are the most common immunological diseases. They strike

Type II allergic reactions The second type of allergic reactions is called cytotoxic immune reactions. This type of allergy is characterized by the combination of allergen with cells first, and then antibodies with the allergen-cell system. With such a triple connection and

III type of allergic reactions The third type of allergic reactions is immunocomplex, it is also called "immune complex disease". Their main difference is that the antigen is not bound to the cell, but circulates in the blood in a free state, without being attached to the components.

IV type of allergic reactions Antibodies do not participate in reactions of the fourth type. They develop as a result of the interaction of lymphocytes and antigens. These reactions are called delayed reactions. Their development occurs 24-48 hours after ingestion.

Stages of allergic reactions All allergic reactions in their development go through certain stages. As you know, getting into the body, the allergen causes sensitization, i.e. immunologically increased sensitivity to the allergen. The concept of allergy includes

The hypersensitivity reaction of the body can proceed according to different scenarios. There are four types of allergic reactions in total.

In fact

After a substance of an antigenic nature enters the body, the immune system develops a response in the form of the formation of antibodies, the formation of immune complexes, or the reaction of sensitized lymphocytes. That is, developing allergic reaction. At the beginning of the last century, the American physician Robert Cook proposed to divide all allergic reactions into two types - immediate and delayed. However, this division was incomplete, and in 1969 the immunologists Coombs and Jell proposed a new classification, according to which four main types of allergic reactions are distinguished. Although in some literature there is also a fifth.

It should be noted that during the development pathological process almost all types of reactions of the immunocompetent system are involved, which creates some difficulties for determining the leading type.

I type of reactions

The first type of allergic reactions, as a rule, develops in the first few minutes (or hours) after contact with the allergen. This is an allergic reaction of the anaphylactic type, caused by the interaction of the antigen with reagin or specific antibodies on the surface of the mast cell ( immune cells connective tissue). These interactions lead to the release a large number histamine and a number of other vasoactive substances that dilate blood vessels, increase the permeability of the vascular wall and increase contractile activity smooth muscles (which can cause spasms of smooth muscles).

In the vast majority of cases, allergic reactions of the first type occur with the participation of immunoglobulins E, in rare cases - immunoglobulins G.

Typical examples of a type 1 allergic reaction are urticaria, atopic bronchial asthma, vasomotor rhinitis, false croup. In allergic bronchial asthma, as a result of antigen-antibody interaction, spasms of the smooth muscles of the bronchioles occur, which is accompanied by swelling of the mucous membrane and secretion of a large amount of mucus.

II type of reactions

The second type of allergic reaction, also called cytotoxic or cytolytic, occurs with the participation of immunoglobulins G and M. The reaction of the second type, as a rule, proceeds more slowly than the first, and usually begins more than 6 hours after contact with the allergen. The reaction of the second type is characterized by the interaction of circulating antibodies with the antigens of a person's own cells. In this case, the death of the cell or a significant decrease in its basic functions occurs.

This type of allergic reaction is typical for drug allergies. , hemolytic anemia, thrombocytopenia and with Rhesus conflict.

ІІІ type of reactions

This type of allergic reaction is known as the Arthus phenomenon or immune complex reaction. This type of reaction develops, as a rule, after 6-12 hours (or several days) after the patient's contact with the allergen. In this case, precipitating immune complexes with an excess of antigens are formed, which are subsequently deposited on the walls of blood vessels, and thereby provoke the development of inflammatory processes.

The third type of allergic reactions develops with allergic conjunctivitis, systemic lupus erythematosus, immunocomplex glomerulonephritis, serum sickness, rheumatoid arthritis and allergic dermatitis.

As in the second type of reactions, in this case the process also proceeds with the participation of immunoglobulins G and M.

Questions from readers

Good day! I've been sick with bronchitis for 3 weeks now October 18, 2013, 17:25 Good day! I've been sick with bronchitis for 3 weeks now. In me, for the second time, the gut is alive, to sleep out at once with me in my bed. Even the fathers have a whale, which one we have more fate. Were already at the Institute of Pulmonology, everything is fine with the lungs, the result for asthma is negative (the two were reconsidered). For three weeks I have had a persistent cough and see a lot of drooling. During the day it’s nothing, but at night there are seizures - I throw up sharply and I can’t breathe again, until I cough up all the saliva (it won’t accumulate and won’t let you breathe). The attack here is 1-2 minutes, I can’t breathe in, until I cough. The nose is not congested. The therapist and pulmonologist heard, they said that such a thing could not happen to bronchitis, wanting to hear wheezing. How can you blame an allergy to a cat in 1.5 years, how is it alive in me, as there were no earlier manifestations? What can cause allergy against the background of bronchitis?

IV type of reactions

The fourth type of allergic reactions is a variant of late hypersensitization, which develops 24-72 hours after the patient has come into contact with the allergen. This type of reaction is due to the interaction of the antigen and the T-lymphocyte sensitive to it. In the case of repeated such contact, specific delayed-type inflammatory reactions develop. For example, it could be allergic dermatitis, or such a reaction can be observed with graft rejection.

Most often, with the fourth type of allergic reactions, the skin, respiratory organs and gastrointestinal tract, although absolutely all organs and tissues can be involved in the process.

The attention of the general reader is offered a book on one of the most pressing problems modernity - allergies. Perhaps there is not a single person who has not heard this strange word. And what does it mean? Is this a disease or a normal manifestation of the body? Why and who gets allergies? Can it be cured? How to live on for a person who has an allergy? All these questions and many more are answered by the author of this book. The reader will learn about the causes of the development and exacerbation of allergies, the most various methods treatment and prevention of this condition.

Types of allergic reactions

Depending on the time of occurrence, all allergic reactions can be divided into 2 large groups: if allergic reactions between the allergen and body tissues occur immediately, then they are called immediate-type reactions, and if after a few hours or even days, then these are delayed-type allergic reactions. According to the mechanism of occurrence, 4 main types of allergic reactions are distinguished.

Type I allergic reactions

The first type includes allergic reactions (hypersensitivity) of the immediate type. They are called atopic. Allergic reactions of immediate type are the most common immunological diseases. They affect approximately 15% of the population. Patients with these disorders have abnormal immune responses called atopic. Atopic disorders include bronchial asthma, allergic rhinitis and conjunctivitis, atopic dermatitis, allergic urticaria, angioedema, anaphylactic shock, and some cases of allergic lesions of the gastrointestinal tract. The mechanism of development of the atopic state is not fully understood. Numerous attempts by scientists to find out the causes of its occurrence have revealed a number of characteristics that distinguish some individuals with atopic conditions from the rest of the population. Most feature such people is a disturbed immune response. As a result of the impact of the allergen on the body, which occurs through the mucous membranes, an unusually high amount of specific allergic antibodies is synthesized - reagins, immunoglobulins E. In people suffering from allergies, the content of another important group antibodies - immunoglobulins A, which are the "defenders" of the mucous membranes. Their deficiency opens access to the surface of the mucous membranes. a large number antigens, which ultimately provokes the development of allergic reactions.

In such patients, along with atopy, the presence of dysfunction of the autonomic nervous system is also noted. This is especially true for people suffering from bronchial asthma and atopic dermatitis. There is an increased permeability of the mucous membranes. As a result of the fixation of so-called reagins on cells with biologically active substances, the process of damage to these cells increases, as well as the release of biologically active substances into the bloodstream. In turn, biologically active substances (BAS) with the help of special chemical mechanisms damage already specific organs and tissues. The so-called "shock" organs in the reaginic type of interaction are primarily the respiratory organs, intestines, and conjunctiva of the eyes. BAS reagin reactions are histamine, serotonin and a number of other substances.

In the reaginic type of allergy, there is sharp rise permeability of the microvasculature. In this case, the fluid leaves the vessels, resulting in the development of edema and inflammation, local or widespread. The amount of discharge of mucous membranes increases, bronchospasm develops. All this is reflected in clinical symptoms.

Thus, the development of immediate type hypersensitivity begins with the synthesis of immunoglobulins E (proteins with antibody activity). The stimulus for the production of reaginic antibodies is exposure to the allergen through the mucous membrane. Immunoglobulin E, synthesized in response to immunization through the mucous membranes, is rapidly fixed on the surface of mast cells and basophils, located mainly in the mucous membranes. With repeated exposure to the antigen, immunoglobulin E fixed on the surfaces of mast cells is combined with the antigen. The result of this process is the destruction of mast cells and basophils and the release of biologically active substances, which, damaging tissues and organs, cause inflammation.

Type II allergic reactions

The second type of allergic reactions is called cytotoxic immune reactions. This type of allergy is characterized by the combination of allergen with cells first, and then antibodies with the allergen-cell system. With this triple connection, cell damage occurs. However, another component is involved in this process - the so-called complement system. Other antibodies are already involved in these reactions - immunoglobulins G, M, immunoglobulins E. The mechanism of damage to organs and tissues is not due to the release of biologically active substances, but due to the damaging effect of the above-named complement. This type of reaction is called cytotoxic. The “allergen-cell” complex can be either circulating in the body or “fixed”. Allergic diseases that have a second type of reaction are the so-called hemolytic anemia, immune thrombocytopenia, pulmonary-renal hereditary syndrome (Goodpasture's syndrome), pemphigus, and various other types of drug allergies.

III type of allergic reactions

The third type of allergic reactions is immunocomplex, it is also called "immune complex disease". Their main difference is that the antigen is not associated with the cell, but circulates in the blood in a free state, without attaching to tissue components. In the same place, it combines with antibodies, more often of classes G and M, forming antigen-antibody complexes. These complexes, with the participation of the complement system, are deposited on the cells of organs and tissues, damaging them. Inflammatory mediators are released from damaged cells and cause intravascular allergic inflammation with changes in surrounding tissues. The above complexes are most often deposited in the kidneys, joints and skin. Examples of diseases caused by reactions of the third type are diffuse glomerulonephritis, systemic lupus erythematosus, serum sickness, essential mixed cryoglobulinemia and prehepatogenic syndrome, which manifests itself with signs of arthritis and urticaria and develops when infected with the hepatitis B virus. Increased vascular permeability plays a huge role in the development of immune complex diseases , which may be exacerbated by the development of an immediate hypersensitivity reaction. This reaction usually proceeds with the release of mast cell contents and basophils.

IV type of allergic reactions

Antibodies do not participate in reactions of the fourth type. They develop as a result of the interaction of lymphocytes and antigens. These reactions are called delayed reactions. Their development occurs 24-48 hours after the allergen enters the body. In these reactions, the role of antibodies is assumed by lymphocytes sensitized by the intake of the allergen. Due to the special properties of their membranes, these lymphocytes bind to allergens. In this case, mediators, the so-called lymphokines, are formed and released, which have a damaging effect. Lymphocytes and other cells of the immune system accumulate around the place of entry of the allergen. Then comes necrosis (tissue necrosis under the influence of circulatory disorders) and the replacement development of connective tissue. This type of reaction underlies the development of some infectious-allergic diseases, for example contact dermatitis, neurodermatitis, some forms of encephalitis. It plays a huge role in the development of such diseases as tuberculosis, leprosy, syphilis, in the development of transplant rejection, in the occurrence of tumors. Often, patients can combine several types of allergic reactions at once. Some scientists distinguish the fifth type of allergic reactions - mixed. So, for example, with serum sickness, allergic reactions of the first (reaginic), second (cytotoxic), and third (immunocomplex) types can develop.

As our knowledge of the immune mechanisms of tissue damage development increases, the boundaries between them (from the first to the fifth type) become more and more vague. In fact, most diseases are caused by the activation different types inflammatory reactions that are interconnected.

Stages of allergic reactions

All allergic reactions in their development go through certain stages. As you know, getting into the body, the allergen causes sensitization, i.e. immunologically increased sensitivity to the allergen. The concept of allergy includes not only an increase in sensitivity to any allergen, but also the realization of this increased sensitivity in the form of an allergic reaction.

Initially, sensitivity to the antigen increases, and only then, if the antigen remains in the body or enters it again, does an allergic reaction develop. This process can be divided in time into two parts. The first part is preparation, increasing the body's sensitivity to an antigen, or, in other words, sensitization. The second part is the possibility of realizing this condition in the form of an allergic reaction.

Academician A.D. Ado singled out stage 3 in the development of allergic reactions of the immediate type.

I. Immunological stage. It covers all changes in the immune system that occur from the moment the allergen enters the body: the formation of antibodies and (or) sensitized lymphocytes and their combination with the allergen that has re-entered the body.

II. The pathochemical stage, or the stage of the formation of mediators. Its essence lies in the formation of biologically active substances. The stimulus for their occurrence is the combination of the allergen with antibodies or sensitized lymphocytes at the end of the immunological stage.

III. Pathophysiological stage, or stage of clinical manifestations. It is characterized by the pathogenic action of the formed mediators on the cells, organs and tissues of the body. Each of the biologically active substances has the ability to cause a number of changes in the body: dilate capillaries, lower blood pressure, cause spasm of smooth muscles (for example, bronchi), disrupt capillary permeability. As a result, a violation of the activity of the organ in which the incoming allergen met with the antibody develops. This phase is visible to both the patient and the doctor, because the clinical picture of an allergic disease develops. It depends on which way and to which organ the allergen entered and where the allergic reaction occurred, on what the allergen was, and also on its quantity.

Allergy is familiar to almost every person, and what it really is, what symptoms will indicate the progression of an inadequate reaction of the body to a specific stimulus, how to provide first aid and how treatment should be carried out is known only to a few.

Meanwhile, allergy is considered one of the most common diseases in the world - 85% of the entire population of our planet to some extent endured an allergic reaction.

General information about allergies

Allergy - this is hypersensitivity body to a stimulus. Such provoking substances can be those that are inside the human body, and those with which there is contact. The body of people prone to allergies perceives absolutely safe / habitual substances as dangerous, alien and begins to produce antibodies against them. Moreover, an “individual” allergen is produced for each irritating substance - that is, an allergy to tulip pollen, animal hair and / or milk can manifest itself in different ways.

As such, there is still no cure for allergies. Modern medicine is constantly conducting various studies and looking for ways to solve this problem, but there are no tangible results yet. What can be done at the moment:

• by identifying the allergen;
• take that can relieve the symptoms of the disease in question;
• limit contact with the identified allergen as much as possible.

Reasons for the development of allergies

It is impossible to single out any one reason for the development of allergies - there are a lot of predisposing factors that can provoke the condition in question. To these include:

• street, book and / or home;
• spores of fungi and mold;
• pollen of any plants;
• (the most common allergens include milk, eggs, fish and seafood, some fruits and nuts);
• insect bites;
• cleaners and detergents;
• any chemicals - paints, gasoline, varnishes, solvents, and so on;
• animal hair;
• some medicines;
• latex.

Allergies are often hereditary disease- at least, medicine knows cases when the presence of allergies in parents necessarily affects the health of their children.

Types of allergies and symptoms

The presence of any specific symptoms depends on which form of the disease in question is present in a person.

Respiratory Allergy

It develops against the background of allergens entering the body through the respiratory tract. Symptoms of this type of allergic reaction will be the following phenomena:

Note:the main symptoms are respiratory allergies are considered and (rhinitis).

Dermatosis

Accompanied by pronounced manifestations on the skin - rashes, irritation. Symptoms include:

• redness of the skin - it can be localized and appear only in places of direct, and maybe frontal;
• the skin becomes dry, flaky and itchy;
• rashes that mimic appear and spread rapidly;
• blisters and intense swelling may be present.

allergic conjunctivitis

In this case, an inadequate reaction of the body to any irritant will be manifested by a deterioration in the health of the eyes. Symptoms of this type of allergy are:

• increased lacrimation;
• swelling present around the eyes.

Enteropathy

This is an allergic reaction of the body, which is manifested by a disorder of the gastrointestinal tract. Most often, enteropathy develops on food, drugs. Symptoms of this type of allergy are:

• (diarrhea);
• pain in the intestinal region of varying intensity (intestinal).

Note:it is with enteropathy that it can develop - the lips and tongue swell, the person begins to suffocate.

Anaphylactic shock

Exactly this dangerous manifestation allergies, which always develops rapidly. In just a few seconds, the patient appears:

• intensive;
• convulsive syndrome;
• involuntary urination and defecation;
• pronounced rash all over the body;

Note:if a person has the above symptoms, then you need to immediately call the ambulance team, or take the patient yourself to medical institution. , as a rule, ends in death in the absence of qualified medical care.

It is worth noting that allergy symptoms are very often confused with symptoms colds- , . But it is quite easy to distinguish an allergy from an allergy - firstly, with allergies, the body temperature remains within the normal range, and secondly, a runny nose with allergies is never characterized by thick, greenish-yellow mucous secretions.

How a specific allergen is detected

If they appear allergic symptoms, but the specific irritant is not known, then you will need to seek help from specialists. In addition to the fact that the doctor will make an accurate diagnosis, he will refer the patient to specific examinations that will help identify the true allergen. These surveys include:

1. Skin tests. The advantage of this method of examination is the simplicity of the procedure, the speed of obtaining results and low cost. Some skin test facts:

At positive reaction redness, itching and swelling appear at the site of application of the allergen.

Note:2 days before the scheduled date skin tests the patient is forbidden to take any antihistamine drugs, as this can lead to false results.

1. . Blood is taken from a vein, which is then sent to the laboratory for analysis. The results will be ready in 10-14 days.

Doctors note that this type of examination cannot give a complete answer to the question of the causes of allergies.

1. Skin tests. This examination is carried out for dermatoses - conditions in which an allergy manifests itself on the skin. This method can determine the body's reaction to:

• formaldehydes;
• chromium;
• benzocaine;
• neomycin;
• lanolin;
• corticosteroids;
• epoxy resins;
• rosin.

1. provocative tests. This examination is considered the only one that gives a 100% correct answer to the question of which irritant provoked the development of an allergy. Provocative tests are carried out only in a specialized department under the supervision of a group of doctors. A possible allergen is introduced into the respiratory tract, gastrointestinal tract, under the tongue, into the nasal cavity.

First aid for allergies

If there are signs of an allergy, then you need to give the patient first aid. The best option would be to immediately consult a doctor, but if this is not possible, then you should perform the following manipulations:

If within 20-30 minutes the patient's condition has not improved, and even more so if it has worsened, then you should immediately call the ambulance team.

In some cases, severe symptoms of an allergic reaction may develop:

• suffocation;
• and uncontrollable vomiting;
• increased heart rate and respiratory rate;
• swelling of the whole body, including the pharynx;
• general weakness;
• a growing sense of anxiety;

And the above symptoms indicate that the patient is facing fatal outcome- needs to be done Urgent measures to stabilize his condition. Go to events intensive care relate:

• if the patient is conscious, then they give him to drink any antihistamines, it is better to use ;
• the patient must be put to bed, take off his clothes, turn his head to one side;
• when breathing and heartbeat stop, it is urgent to do artificial respiration and , but only if certain knowledge is available.

Allergy treatment

An allergic reaction has complex mechanism development, so the treatment will be selected by doctors on a strictly individual basis and only after the examination of the patient. Antihistamine drugs are most often prescribed, immunotherapy is carried out, steroid sprays can be used for allergic rhinitis(runny nose) or decongestants.

In addition, the patient must take care of his own health - exclude contact with the allergen, regularly carry out maintenance therapy, treat inflammatory / infectious / viral diseases in a timely manner in order to work fully. Do not forget that there is an allergy to drugs, and in this case you will need to know specific means to exclude them in the treatment of any diseases.

Allergy is a complex disease that needs to be controlled both by the patient and by medical workers. Only accurate knowledge of a specific allergen that provokes the development of the disease in question, conducting timely treatment can improve the health and improve the life of the patient.