General (clinical) blood test
12.04.2019

Allergens of infectious origin. Development of an allergic reaction to metals

ONE CURIOUS medieval doctor, watching a worker clean out his drain very quickly, asked the obvious question: why was he working so fast? The worker replied that spending a long time in such a harmful environment Irritates the eyes and may cause blindness.
So in the late 1600s it was noted key moment in the birth of professional health. Italian physician Bernardino Ramassini continued to research diseases commonly found in various professions, including artists, rural workers, fishermen, caregivers, and food processors.

Some 300 years later, these same occupations still figure prominently in lists of jobs that can cause allergic conditions such as skin rash, runny nose, itchy eyes, asthma and anaphylaxis.
Many workplaces use substances that can irritate the lungs, nose, skin, eyes, or enter the body causing a reaction immune system. There are at least 250 known substances that can cause occupational asthma, and the list of usual suspects grows every year as more nuisance products are identified.

Some occupations are known for specific ingredients that make most workers sick. Chemicals called di-isocyanates, which are used in spray paints to make plastics and polyurethane products, are the leading cause of occupational asthma in industrialized countries. Latex products cause many nurses, doctors and other healthcare workers to develop allergic reaction- from skin irritation to life-threatening shock.
And an enzyme used in the detergent was blamed for an epidemic of asthma among workers who handled the material in the 1960s and 1970s.

If allergens or irritants are used in your work, the solution may vary. In some cases, it is enough to use a mask, gloves, etc. protective equipment to protect yourself from exposure to harmful substances. If your exposure to this allergen or irritant is significant, you may have to convince your employer to transfer you to another location or company.

But for many sick people, exposure to an allergen or irritant can be simply life-threatening. The most The best decision for health is simply to avoid exposure to a harmful substance. This may mean that if your employer is unable or unwilling to make accommodations that would prevent allergy symptoms, then you may have to find a new job.
This may be a difficult decision, but the problem cannot be ignored.
Luckily, a doctor with good research skills can help identify what's making you sick. And you can do a lot to protect your health by taking notes, working carefully, collecting important information about your workplace and maintaining a good relationship with your employer.

Main players

See how your work can contribute to the development of major allergic conditions: asthma, skin problems and allergic rhinitis, and you'll see how complex workplace allergies can be (for more detailed information on these diseases, see the sections dedicated to them).

As a sawmill operator cuts a tree trunk amid a downpour of sawdust, he feels the familiar tightness in his chest of an approaching asthma attack.
If the workplace creates breathing problems, it is as important an issue as salary and should be taken very seriously.
There are several cases of people dying from occupational asthma after it was diagnosed. Worldwide, at least 10 percent of asthma cases that affect adults can be linked to the workplace. This includes previously healthy people who acquired asthma at work, and those who had the disease and aggravated it under the influence of harmful substances to which they were exposed during work. Both of these situations pose health risks and need to be addressed from a medical perspective.

Sometimes asthma occurs due to an allergen. It usually takes months or years of exposure before symptoms begin to be felt because the body's immune system takes time to produce an allergic reaction. This is the type of situation that exists among veterinarians who become allergic to cat dander and sawmill workers who develop asthma from wood dust.

Asthma symptoms may appear an hour after you are exposed to the allergy trigger and disappear within 1-3 hours after it is removed, or it may take several hours for symptoms to come and go. Adding insult to injury, symptoms may return up to 12 hours after you have recovered from your initial encounter.
But asthma in the workplace is not always caused by allergens. Irritants such as hydrochloric acid and sulfur dioxide, can cause wheezing immediately after you encounter them. The reaction that occurs after you inhale large amounts of an irritant, such as toxic fumes or gases from a leak, is called RADS, or reactive dysfunction syndrome respiratory tract. This can have long-term consequences, keeping you out of action for a long time.
Another cause of asthma is the inhalation of certain aerosolized chemicals, such as small amounts of insecticides used in agriculture, which cause natural substances histamine and acetylcholine are produced in the body and constrict the airways.

Several factors increase the chances of getting work-related asthma. Atopicity, or predisposition to the presence of allergic diseases, is a factor increased risk. Smoking also increases the likelihood of developing work-related asthma, worsens it if you already have it, and creates additional problems in proving a work-related asthma link.

If your asthma is truly work-related, you will likely notice that your asthma symptoms increase during the week and decrease on the weekends. But problems can persist throughout the weekend, becoming almost continuous (which makes it difficult to find the source).

Skin problems

After a hairdresser gives a client a perm, his hands break out in an itchy rash.
Occupational skin diseases affect up to 20 percent of people with occupational diseases. Of all skin problems, by far the most common is contact dermatitis caused by irritants and allergens (3/4 cases).
The most common patients of allergists are hairdressers, who, due to the nature of their work, often come into contact with water and chemicals, bartenders and food handlers, who often immerse their hands in soapy water.
Water and soap are sources of irritant contact dermatitis, as are solvents, resins, fats, glass fibers, acids and alkalis. Allergic contact dermatitis can be caused by components of cosmetics, rubber and epoxy resins, poison ivy and oak. Some substances can act as both irritants and allergens.

Irritant contact dermatitis is detected within minutes to several days after exposure to a harmful substance. The boundaries of the rash are often sharply defined, and then it completely disappears within 4 days.
Allergic contact dermatitis, however, only affects people who have already become sensitive to this substance. They experience intense itching and red, fluid-filled blisters may appear on the affected area. The rash, which is not definitely caused by irritants, may appear 1-6 days after exposure to the harmful substance and will take at least a week to resolve.

Another skin condition that may be caused by the work environment is urticarial rash, or urticaria. It occurs within a period of time from several minutes to an hour after contact with a harmful substance and disappears within a few hours. It can be caused by latex and foods such as seafood, fruit and cheese.
The risk group of people most susceptible to these skin diseases are people with atopic dermatitis, a condition in which the skin is extremely sensitive and overreacts to substances it comes into contact with. If you've ever had atopic dermatitis, even as a child, think twice about working as a hairdresser or cook, where wet hands will often come into contact with irritants and allergens.

Allergic rhinitis

A graduate student sneezes as she examines the itchy eyes of the lab rats in the cages surrounding her.
Lab rats used for experiments often take “revenge” on the white-coated workers who surround them. Laboratory workers are one of the groups most often affected by work-related rhinitis, and rats are the most common source of allergens.
Allergic rhinitis, more commonly known as hay fever, causes symptoms such as a runny and swollen nose, sneezing, itchy palate, watery eyes and itchy eyes. It can be caused by allergens, irritating odors (such as perfume), fumes and particles (cigarette smoke, coal dust and emissions of concentrated chemicals such as chlorine).
Of course, this is not just a problem for laboratory workers. Psullium, an ingredient in laxative medications, can cause rhinitis in pharmacists who prepare the medicine and in nurses who administer it to patients. Guar gum, used to thicken foods and color carpet fibers, can cause rhinitis in workers.

Although rhinitis is also a work environment condition, it has not received as much attention as asthma, perhaps because it is not as severe or potentially dangerous. Because rhinitis really causes unpleasant symptoms and may appear before or along with asthma, certain measures must be taken if it appears.
If your rhinitis is work-related, you will likely notice symptoms at work, but they may continue later in the evening as the body takes time to respond to allergens and irritants. And at the time when you feel better, i.e. On weekends and holidays, mild symptoms may continue for several more days before finally disappearing.
Now that we know how work-related allergies manifest themselves, it's time to learn what to do about them.
It's hard work.

Show professional allergies who's boss

As you've learned in this book, living an allergy-free lifestyle requires a bit of detective work. And if you want to overcome workplace allergies, then curiosity, observation and communication skills can play a determining role in how successful you are.
In this chapter, experts will share confidential information about how to work with your doctor, employer, and workers' compensation system to get what you need.

Your doctor

Bernardino Ramassini, the founder of professional medicine mentioned earlier, often visited his patients' workplaces, no matter how unpleasant they were. And modern experts emphasize the importance of doctors visiting workplaces to make observations and conclusions.
In the real world, however, convincing a busy doctor to come to your workplace is about as likely as getting compensation from the company for a sore foot at the end of the day. Although occupational skin conditions are very common, most doctors don't want to deal with them because they make twice as much money solving cosmetic problems.
While an allergist is a good option for treating any of these conditions, a dermatologist may be best choice for skin diseases, pulmonologist - for lung problems, and an otolaryngologist - for rhinitis. You can also contact an occupational health professional for additional expertise to help address the problem in your situation. Since time is precious, what more information you bring it to the doctor's office, the better.

Here's what you need to collect:
your story. The more documentation the patient brings, the faster and better the doctor can make an assessment. Provide your doctor with detailed information about previous illnesses, any allergies in your family or yourself, medications you are taking or using, and bad habits such as smoking. Also include full descriptions existing and previous job responsibilities and characteristics of the workplace environment;
diary. Make very detailed notes on your work schedule and symptoms, including whether they occur at work or when you are not at work. This will help determine how symptoms arise and may even show that you are allergic to something unrelated to your work;
MSDS. This is an acronym for “Contained Material Data Lists.” Companies that use some chemical substances, are legally required to have lists that describe the substances used and offer accessible information on safe methods working with them. Not only should you use them and learn how to handle any chemicals present at work, you need to take them to the doctor. These lists are important to understand the nature of the chemicals you handle at work, understand their potential adverse health effects, and provide recommendations for protection. If you suspect you have a health problem, bring the MSDS to your doctor so he can become familiar with the chemicals and their properties. Many high-tech industries use a myriad of agents that would not be suspected if MSDS were not available.

Depending on the specific circumstances, the doctor will use the information you provide, a physical examination, and possibly a variety of tests to pinpoint the source of the allergen.

Asthma. Your doctor may prescribe skin test to see if you have allergies to proteins, such as animal dander or soy. When uncertain bronchial disease you may need to be tested for asthma by inhaling histamine or methacholine to determine how much your lungs react to them.

The doctor may also ask you to use an airflow meter - an inexpensive, simple device that is small in size and therefore suitable for testing at home and at work and recording the results.
The gold standard for proving occupational asthma, however, involves exposing you to certain suspected substances and observing your response to them. This, however, requires special equipment and medical professionals who can help if it occurs. acute reaction on the substance.

Skin problems. Your doctor can test your exposure to many possible allergens by applying them to your skin and covering them with a bandage. Since all standard allergen test kits available may not be exhaustive, you may need to bring samples of each suspected substance you encounter on the job.

Rhinitis. The doctor may do a skin test to see if you are allergic to specific proteins. In a simple test called a nasal challenge, the doctor will expose your nose to a suspected substance, then examine the surfaces of your mucous membranes to look for any changes, and perhaps take measurements of the air flow through your nose.
The single best solution to nipping an occupational allergy in the bud is to avoid exposure to the offending substance. Simply treating your symptoms with medication only masks a bad situation, and in the case of asthma, exposure to large amounts trigger mechanisms may have fatal results.

Given your individual circumstances, you may not have to leave your job and look for another. Instead, you can change the type of work you do with your employer to make it suitable for your health.
Since many of us have environmental constraints, it is necessary to work closely with observers to find the right solution.

Your employer

If the doctor can prove that a substance you come into contact with at work is harmful to your health, ask him to report this to your employer, along with a recommendation on what type of changes are needed. In this case, the employer must do something to help make the necessary changes, but not necessarily the ones you would prefer. This means that, as an entrepreneur, he can think of a cheaper or any less onerous way to fulfill the requirements that he is obliged to fulfill. Some laws can help you with this.
But not all potentially harmful substances are regulated. Levels of chemicals known as isocyanates are regulated, but dust from wheat flour, which causes asthma in bakers, is not. Moreover, the regulations are designed to protect workers in general rather than the individual worker with his or her specific need.

Regardless of whether you have legal support, your requests will be more listened to if you become an ally of the labor watchdog instead of being seen as their opponent. Do not contact an attorney right away; involving an attorney in solving a problem from the very beginning may create an adversarial situation that will not achieve the desired result.
The next best solution may be administrative control, as a result of which the sick person is moved to another production environment. This could mean shorter hours, doing a different job, or doing the same job in a different location. For example, lab workers who are sensitive to mice usually react to protein in their urine and may perform necropsies on the animals while away from the urine-soaked cages.

The choice that doctors least approve of, but which employees must often make because it is easiest for employers to make, is that workers wear protective equipment, such as a mask or respirator to avoid breathing in dust, or wear gloves to hold hands dry. The employer retains the right to permit the voluntary use of a mask. Sometimes masks are complex, requiring filters or cartridges to be replaced regularly.
No matter what the employer chooses, they will have many potential reasons to try to give you a job. The cost of the compromise may be less than the cost of finding and training a new employee. Plus, if an employer understands that you'll have good working conditions, they won't want to risk the time and money they pay out in workers' compensation, and it's more beneficial for them to have healthy workers, Dr. Riscitelli says.

Allergens- these are antigens causing allergies. Under certain conditions, the properties of allergens can be acquired by factors of a diverse nature, primarily all high- and low-molecular substances of organic and inorganic origin. The list of industrial allergens exceeds a hundred items and includes haptens(formaldehyde, epichlorohydrin, furan, diisocyanate, aromatic nitrobenzenes, ursol, salts of chromium, nickel, cobalt, manganese, platinum, etc.) and full antigens(synthetic polymer materials, components of varnishes, resins, adhesives, elastomers, cements, compounds, etc.).

In industry, workers also encounter allergens. natural composition: dust of grain, flour, tobacco, cotton, wool and animal dander, plant pollen. The latter, being household allergens, can also cause occupational diseases.

The mechanisms of formation of allergies to industrial allergens depend on the properties of the allergen itself and its combination with other factors. Allergic reactions to full(high-molecular-weight) allergens according to the mechanism of development correspond to non-occupational allergies: hypersensitivity, manifested in immediate-type reactions, delayed-type reactions, antibody-dependent cytotoxicity, immunocomplex cytotoxicity, granulomatous reaction.

Allergy to haptens(low molecular weight allergens) is formed due to the formation of the so-called “complex antigen”, i.e. compounds of hapten with protein molecules.

The route of entry of the allergen into the body, as a rule, determines the form of occupational allergic disease. When inhaled, allergic diseases of the respiratory system develop, and when taken through the skin, skin diseases develop. Long-term exposure to these substances disrupts the barrier function of the mucous membranes and skin, which increases their permeability to the allergen, resulting in the formation of professional

sional allergic disease in the form of rhinitis, sinusitis, rhinosinusitis, pharyngitis, nasopharyngitis, bronchial asthma, asthmatic bronchitis, exogenous allergic alveolitis, epidermitis, dermatitis, eczema and toxicoderma. These forms of diseases are most often observed in the chemical industry (among operators at chemical-pharmaceutical and chemical plants), workers in the woodworking and electronics industries, in the construction industry, the production of polymer materials, biotechnology, medicine, etc.

The risk of developing occupational allergic diseases largely depends on the conditions of exposure and the entire complex of occupational factors. In this case, the routes of entry and concentration of allergens, exposure modes and dose loads play a particularly important role. Under production conditions, there is an unfavorable course (hypersensitivity) of allergic reactions with complex exposure to allergens. Finally, an important place is occupied by the increased individual sensitivity of the body.

The effects of irritation of the mucous membranes of the respiratory tract and

skin. As a result of their mechanical traumatization (quartz dust), maceration of the skin associated with high humidity with increased sweating in a heating microclimate, an increase in allergenic effect is observed when exposed to skin chemical product.

The phenotype of allergic diseases is fundamentally different from the forms of response of a healthy body to industrial allergens and, first of all, in that the sensitization reaction develops against the background of the functional activity of the T- or T- and B-immune systems.

It should be noted that in modern production conditions, in combination with or without allergens, the body of workers can be exposed to substances that cause clinically similar reactions to those of a true allergy. This applies to compounds with immunomodulating and immunotoxic effects. Moreover, depending on the characteristics of the immune and biochemical status of the worker, the reactions are dominated by allergic or toxic-allergic responses or non-immune direct degranulation of tissue basophils with hyperproduction of inflammatory mediators and bronchospasm.

In this regard, as a rule, a comprehensive assessment of the state of cells of the immune system and other inflammatory cells, their mediators, cytotoxins, antibodies is carried out for the purpose of diagnosis, examination and prognosis. Using this approach, such forms of occupational diseases as berylliosis, bronchial asthma (when exposed to solvents), metalloconiosis, byssinosis and

etc.

Main way prevention of occupational allergic diseases- hygienic regulation of allergens in the air of the working area and skin contamination, taking into account their specific sensitizing effect.

An important place in the system of prevention of occupational allergic diseases is occupied by the diagnosis of their early signs with subsequent treatment, identification of individuals with a genetic or acquired predisposition to allergic reactions and the formation of risk groups.

Currently, specialized allergological examinations of industrial workers are carried out by research institutions. In accordance with the long-term program of medical examination of workers, work on

training of allergists, immunologists and occupational pathologists and the introduction into the practice of health care at enterprises of express and microvariants of immunological tests for quantitative and functional assessment of the immune system. The effectiveness of the prevention of occupational allergic diseases depends on a set of measures, including socio-economic, sanitary and hygienic, therapeutic and preventive elements and sanitary educational work.

There is a certain number of people whose skin reacts inadequately to contact with various metals. A metal allergy can occur on a belt buckle, dental prosthesis, earrings, bracelets, etc.

Conducted studies confirm the occurrence of this disease in every tenth case of occurrence, when an allergy to metal and metal-containing alloys is clearly expressed. The localization site is the area of ​​contact with the allergen.

Particular discomfort appears when an allergy to metal occurs in contact with essential items: in the kitchen, in production. In addition, ordinary metal coins and jewelry can cause severe allergic symptoms.

Reasons for the development of the disease

Allergy to metal, the causes of which are a special reaction of the immune system to foreign organisms, may manifest itself in different ways.

  1. The metal has the property of releasing specific ions upon contact with the skin. Especially when interacting with sebaceous secretions and then. The released substances can easily penetrate the subcutaneous layer, manifesting negative symptoms.

  1. When they enter the blood and tissue surfaces, metal trace elements change cellular protein, which leads to the immune system perceiving its own cells as pathological. This causes an acute allergic attack.
  2. It is generally accepted that metal allergies are most common among urban residents. It is there that industry is most developed, the emission products of which contribute to the deterioration of the environmental situation, filling the air with harmful substances.
  3. Another reason for the appearance negative reaction counts high dose irritant, after which the person begins to choke, lacrimation and other typical signs of the disease are noted.
  4. The disease is most susceptible to people with weakened immune systems, after illnesses and with a history of chronic diseases.

  1. Allergic diseases are most common in children. This is due to the immaturity of the immune system.
  2. In addition, it is of no small importance genetic predisposition to allergic diseases and, specifically, to a certain type of metal.

An allergy to metal can have an acute onset, or it can proceed latently, without obvious symptoms. However, in any case, at the first suspicion of this type of allergy, it is recommended to do all kinds of testing and perform specific tests to identify the allergen.

Most allergenic metals

Most often, an allergic reaction occurs as a result of contact with the following metals:

1. Nickel

This type of metal and alloys with its addition are widely used for the manufacture of decorative jewelry, as well as medical equipment, orthopedic products and buttons. Very rarely, the presence of nickel is detected in fish products, orange juice and chocolate. In this case, the allergic reaction is classified as a type of food allergy. To neutralize symptoms, treatment is carried out using a hypoallergenic diet.

2. Chrome

Most often used as anti-corrosion coatings and found in to a greater extent in colors.

3. Aluminum

This metal is used to produce tableware, so the risk group consists of people who have close contact with these products (cooks, kitchen workers, etc.). In addition, aluminum is often added to antiperspirants.

4. Cobalt

It is added to popular cosmetics and hair dyes, so it is mainly women who are at risk.

5. Zinc

Cobalt has found wide application in dentistry. It is added to filling materials.

6. Copper

Copper is mainly used to make jewelry. In addition, coins are made from this metal.

As a rule, metals come into contact with different areas of the skin, and allergic symptoms can be expressed depending on the location.

Precious metals rarely cause negative effects. However, in the manufacture of jewelry, alloys are mainly used, and therefore allergies also occur to precious items. In this case, special treatment is required.

Symptoms of the disease

The most common symptoms of a metal allergy are:

  • unbearable itching;
  • hyperthermia;
  • rashes at the point of contact with metal;

  • keratinization upper layers epidermis, accompanied by peeling;
  • redness of the skin, reminiscent of a thermal burn.

If you identify the symptoms of the disease in a timely manner and begin treatment, you can avoid complications when acute attack Allergies can be caused by a bra clasp or a metal button on clothing.

Allergies in dentistry

The occurrence of allergic reactions to metals in dentistry deserves special attention.

Usually, accompanying symptoms accompanied by regular pain in the oral cavity, stomatitis and the appearance of erosive inflammation in the mouth. In addition, the patient complains of a constant metallic taste in the mouth.

Therefore, in dentistry, special materials for dental crowns are often used: titanium-ceramic, zirconium-ceramic, gold-ceramic.

Treatment tactics

First of all, allergy symptoms upon contact with metal directly depend on the state of the immune system. For recovery, it is recommended to perform various tests and preventive procedures, which include:

  • balanced diet, including more fresh vegetables and fruits;
  • It is recommended to do hardening procedures;
  • it is important to spend more time outdoors;
  • a good effect is observed with dosed physical activity;
  • for obvious allergic symptoms, treatment involves prescribing antihistamines(Claritin, Suprastin, Loratadine, etc.);

  • External treatment is recommended with ointments (Advantan, Polcortolon, etc.). The treatment course lasts a week. The drugs are highly active, so they should be applied to the affected area of ​​the skin in a very thin layer;

Industrial allergens

The rapid development of the chemical industry has significantly increased the number of various chemicals at work and in everyday life, and, consequently, people’s contact with them. This caused the appearance of allergic reactions of various types. The vast majority of industrial allergens are haptens, which bind to proteins through their reactive group. For example, aromatic nitro compounds are added through the halogen atom, mercapto groups of a number of pesticides react with HS groups of proteins, etc. It is believed that the higher the ability of a hapten to form a chemical bond with a protein, the higher its allergenic activity. The most common industrial allergens are turpentine, oils, nickel, chromium, arsenic, tar, resins, tannins, many dyes, etc. In hairdressing and beauty salons, dyes for hair, eyebrows and eyelashes, liquid for perm etc. In everyday life, allergens can be soap, detergents, synthetic fabrics etc.

Allergens of infectious origin

Allergic processes can be caused by a variety of pathogens of infectious diseases, as well as their waste products. These processes become an integral part of the pathogenesis of the disease. Those infectious diseases, in the pathogenesis of which allergies play a leading role, are called infectious-allergic diseases. These include all chronic infections (tuberculosis, leprosy, brucellosis, syphilis, rheumatism, chronic candidiasis, etc.). As epidemic diseases were eliminated, everyone began to acquire great importance allergic processes that are caused by opportunistic and saprophytic flora. The source of sensitization is usually the flora of chronic foci of inflammation in the area paranasal sinuses nose, middle ear, tonsils, carious teeth, gall bladder, etc. In this case, some forms of bronchial asthma, Quincke's edema, urticaria, rheumatism, ulcerative colitis and other diseases may develop. Mushrooms are very common allergens. About 350 species of fungi exhibit allergenic activity. Among them there are species pathogenic for humans that cause diseases with allergies as the basis of pathogenesis. Such diseases are, for example, aspergillosis, actinomycosis, coccidioidosis, histoplasmosis, etc. However, many fungi that are not pathogenic for humans, when they enter the body, cause sensitization and the development of various allergic diseases (bronchial asthma, etc.). These mushrooms are found in atmospheric air, homes, house dust, moldy food products, etc. Their concentration depends on the time of year, humidity, temperature and other conditions.

The most common classification divides all allergic reactions into immediate-type allergic reactions and delayed-type allergic reactions. This classification is based on the time of occurrence of the reaction after contact with the allergen. The immediate type reaction develops within 15-20 min-1 day, the delayed type - after 24-72 hours.

All allergic reactions are divided into true, or actually allergic, and false, or pseudo-allergic (non-immunological).

Pseudoallergy is a pathological process that is clinically similar to an allergy, but does not have an immune stage of its development. Pseudo-allergy is distinguished from true allergy by the absence of the first (immune) stage of development. The remaining two stages are the release of mediators (pathochemical) and pathophysiological (stage clinical manifestations) with pseudo-allergy and true allergy coincide.

Pseudoallergic processes include only those in the development of which the leading role is played by mediators that are also formed in the pathochemical stage of true allergic reactions. The cause of pseudoallergy is any substance that acts directly on effector cells (mast cells, basophils, etc.) or biological fluids and causes the release of mediators from the cells or the formation of mediators in the fluids. Almost the majority of allergens can lead to the development of both allergic and pseudoallergic reactions. This depends on the nature of the substance, its phase, frequency of administration into the body and the reactivity of the body itself. Pseudoallergic reactions occur most often with medicinal and food intolerance. Very many medications more often lead to the development of pseudoallergy than allergies.

Three groups of mechanisms take part in the pathogenesis of pseudoallergy:

  • 1) histamine;
  • 2) impaired activation of the complement system;
  • 3) disturbance of arachidonic acid metabolism.

The clinical picture of pseudoallergic diseases is close to that of allergic diseases. It is based on the development of pathological processes such as increased vascular permeability, edema, inflammation, spasm of smooth muscles, and destruction of blood cells. These processes can be local, organ, systemic. They are manifested by rhinitis, urticaria, Quincke's edema, periodic headaches, disorders gastrointestinal tract, bronchial asthma, serum sickness, anaphylactoid shock, as well as damage to individual organs.

In accordance with the classification proposed by P. Gell and R. Coombs in 1969, there are 4 main types of hypersensitivity reactions:

  • Type 1 - immediate type hypersensitivity. It is caused by the release of active substances from mast cells sensitized by IgE antibodies when they bind an allergen.
  • Type 2 - hypersensitivity caused by the cytotoxic effect of antibodies involving complement or effector cells.
  • Type 3 - immunocomplex reaction. Caused by the pro-inflammatory effect of soluble immune complexes.
  • Type 4 - delayed type hypersensitivity. Associated with the activity of pro-inflammatory T-lymphocytes and macrophages activated by them, as well as cytokines secreted by these cells.

Today, some experts distinguish the 5th type - receptor-mediated.

1. type - anaphylactic,……… classic allergic reaction of immediate type.

The entry of an antigen into the body causes its sensitization. Sensitization is an immunologically mediated increase in the body's sensitivity to antigens (allergens) of exogenous or endogenous origin. The concentration of IgE in the blood serum of a healthy person is lower than that of any other immunoglobulins. It ranges from 85-350 ng/ml. IgE content is expressed in international units - 1 IU = 2.42 ng IgE. IgE is absent in the blood serum of newborns, but starting from 3 months its concentration gradually increases, reaching the level of adults only by 10 years. The IgE content in secretions is higher than in blood serum (it is especially high in colostrum). Most IgE is secreted by lymphoid cells of the mucous membranes. Whey

IgE has short term life - 2.5 days. The production of IgE is also stimulated by the Th2 cytokines IL-5 and IL-6.

Mast cells.

There are a lot of them in barrier tissues, especially in the mucous membranes. In addition to the main factor SCF, the development of mast cells involves cytokines secreted by Th2 lymphocytes and mast cells themselves - IL-4, IL-3, IL-9, IL-10. Mast cells are involved in triggering the inflammatory response and act as effector cells in



Local manifestations of allergies are based on several processes.

Local vasodilation. It manifests itself quickly and is caused by the action of histamine and other preformed factors, and somewhat later by eicosanoids (especially LTC4). The visible manifestation is redness. Increased vascular permeability. Its cause is vascular contraction under the influence of histamine, leukotrienes and platelet aggregation factor (PAF). Leads to the development of edema, promotes extravasation of blood cells. Local disruption of permeability with the formation of leukocyte exudates and hemorrhages forms the basis of skin rashes. The accumulation of fluid in the subepidermal space is the morphological basis of blisters. Spasm of smooth muscles, especially the bronchi. Spasm is caused by eicosanoids (lekotriene C4 and D4, prostaglandin D2, PAF), and to a lesser extent histamine. Manifestation -- asthmatic attack(attack of bronchospasm). Hyperproduction of mucus (nasal, bronchial) and other secretions (for example, tears). Caused by leukotrienes. Accompanies bronchospasm or serves as an independent manifestation of an allergic reaction. Similar phenomena in the intestines cause diarrhea. Irritation nerve endings, leading to the development of itching and pain.


Cytotoxic type of hypersensitivity (type II hypersensitivity) Type II hypersensitivity includes pathological processes that are based only on cytotoxic activity associated with antibodies. This type of hypersensitivity is interpreted as cytotoxic reactions caused by the binding of antibodies to the surface of target cells and the attraction of complement or effector cells to immune complexes, which determine the manifestation of this form of cytotoxicity.

There are several groups of diseases caused by type II hypersensitivity:

alloimmune hemolytic diseases;

hemolytic processes associated with drug hypersensitivity.

Alloimmune hemolytic diseases. This group of diseases includes blood transfusion complications and hemolytic disease of the newborn. The immunological basis of hemolysis caused by incompatibility of ABO blood groups is discussed above. They are associated with the preexistence of antibodies to missing group antigens. That is why transfusion of incompatible red blood cells that bind to antibodies in the bloodstream leads to their massive lysis and the development of complications in the form of jaundice and tissue damage due to the deposition of complexes of membrane proteins of red blood cells with antibodies. Rh conflict hemolytic anemia has a slightly different basis (Fig. 4.36). Among several antigens (C, D, E, c, d, e) of the Rhesus system, the D antigen is the most powerful and is capable of inducing the production of a large number of antibodies. It is encoded by the dominant gene D, the recessive allelic variant of which is the d gene. Conflict situation, caused by incompatibility for these genes, manifests itself not during blood transfusions, but during pregnancy of a Rh-negative mother (with the dd genotype) with a Rh-positive fetus (genotypes DD and Dd). During the first pregnancy, usually no immune disorders occur in the body of the mother and fetus.

III type. If the immune complex elimination system is damaged.

Normally, during the interaction of antigens coming from outside and the antibodies formed, immune complexes, to which complement components bind when activated by classical way. ways. The complexes interact with CR1 (CD35) receptors of erythrocytes. Such red blood cells are absorbed by liver macrophages, which leads to the elimination of the complexes. When antibodies interact with cell membrane antigens of pathogens or other foreign cells, their opsonization occurs, which also contributes to the phagocytosis of these cells. The accumulation of immune complexes in the circulation and their deposition in tissues does not occur in either the first or second situations.

If the system of elimination of immune complexes is damaged (insufficient function of phagocytes or the complement system), prolonged or too massive intake of antigen, as well as the accumulation of a large number of antibodies, the implementation of the processes described above is disrupted. Most an important event in the development of immune complex pathology - the formation of insoluble immune complexes and their deposition in tissues. The transition to an insoluble state is facilitated by an excess of antibodies or a deficiency of the complement system (complement fixation contributes to the preservation of complexes in the soluble phase). Immune complexes are most often deposited on basement membranes, as well as on vascular endothelial cells, which is due to the presence of Fc receptors on their surface. The deposition of complexes contributes to the development of inflammation. The role of triggering factors of inflammation in this case is played by small fragments of complement components C3a and C5a, formed during complement activation. The listed factors, also called anaphylotoxins, cause vascular changes characteristic of inflammation and attract neutrophils and monocytes to the site of deposition of complexes, causing their activation. Activated phagocytes secrete proinflammatory cytokines (IL-1, TNFβ, IL-8, etc.), as well as cationic proteins, enzymes and other active molecules, which causes the development of a full-scale inflammatory reaction. Cell damage can also be caused by activation of complement and the formation of a membrane attack complex. Another factor of damage is platelet aggregation, which occurs during the intravascular formation of immune complexes. It leads to the formation of microthrombi and the release of vasoactive molecules. Immune complex pathology can be caused not only by local deposition of complexes, but also by the systemic action of circulating immune complexes. It is characterized by a combination general symptoms with local inflammatory processes in places where complexes are deposited.

Autoimmune cytotoxic receptor-mediated pathology is precisely this type; some authors classify it as type 5.

Antibodies are produced that can bind to cell receptors, either activating their function or closing the receptor from bioactive substances.

Thus, in type II diabetes, antibodies circulate that competitively bind to insulin receptors, thereby blocking them from insulin.

Delayed type hypersensitivity (type IV hypersensitivity)


Delayed-type hypersensitivity is the only type of hypersensitivity, the direct basis of which is cellular, and not humoral mechanisms. Its prototype is the Mantoux reaction - the response of a sensitized organism to the intradermal injection of tuberculin. The delayed-type hypersensitivity reaction underlies one of two forms of the cellular immune response—inflammatory, caused by CD4+ T cells and their interaction with macrophages. The main result of the sensitizing effect is the development of an immune response inflammatory type with the formation of effector Th1 cells.

The combination of various nosological forms of occupational allergic diseases into a special section is due to the fact that they all represent one of the manifestations of immunity disorders, clinically occurring in the form of various symptom complexes of an allergic reaction. Currently, there is an increase in the incidence of allergic diseases. This is explained by a significant change in the human immune system under the influence of numerous, including chemical environmental factors. These facts acquire even greater significance in the conditions of modern production, where there is a significant duration and intensity of their impact. It is typical that the increase in the number of cases of occupational allergic diseases occurs against the background of a decrease or milder course of occupational intoxications. This is due to the fact that the development and implementation of hygienic standards for the content of industrial toxic substances in the air of working premises does not always ensure safety in relation to the development of allergic reactions, since the threshold doses of the so-called specific, including allergenic, effect of many products are often significantly lower than the threshold toxic doses .

The number of industrial allergens, which include natural and artificial chemicals and compounds, organic products and biological substances with which a significant number of people in a wide variety of industries come into contact National economy, is currently extremely large and is constantly increasing due to the synthesis of new chemical agents and the introduction of new technological processes.

Group of industrial chemical allergens consist of numerous compounds and substances, ranging from simple to extremely complex polymer compositions, sometimes even with an incompletely deciphered structure. Relatively simple chemical compounds with pronounced allergenic activity, extremely widespread in industry, are various sensitizing metals (chromium, cobalt, nickel, manganese, beryllium, platinum and some others), formaldehyde, phthalic and maleic anhydrides, epichlorohydrin, isocyanates, furan compounds , chlorinated naphthalenes, captax, thiurams, neozone D, triethanolamine, etc. These compounds can have a sensitizing effect both on their own and as part of more complex chemical products, released from them during processing and use.

A large group of complex composition allergenic products represent artificial polymeric materials based on formaldehyde (mainly phenol- and urea-formaldehyde resins, adhesives, impregnants, plastics), epoxy polymers based on epichlorohydrin, polyester varnishes, elastomer latexes (in particular, chloroprene and divinylstyrene), polymers based on organosilicon compounds (various brands of lubricants for fiberglass), numerous polymers based on isocyanates, vinyl chloride, acrylic and methacrylic acids, furan, a number of amino acids, etc. Natural polymers, such as shellac and rosin, are also used in industry.

In cases of modern production, chemical allergens can affect the body of workers, being in various states of aggregation. Thus, in the mining industry, the danger of sensitizing effects is associated mainly with dust containing various allergenic metals, and in steel production and during electric welding work - in the form of condensation aerosols. Sensitizing metals pose a significant danger when exposed to inhalation of cement dust, which occurs in cement and asbestos-cement plants, but skin contact of workers with wet cement is also dangerous, in particular in the manufacture of reinforced concrete products. In the rubber industry, both elastomer latexes, many of which have allergenic properties, and numerous technologically necessary components (vulcanization accelerators, antioxidants, antioxidants, etc.) are widely used, among which allergens are captax, thiuram E, neozone D, triethanolamine , rosin and some others. Formaldehyde is found extremely often and in a wide variety of industries, which is not only released during the processing of formaldehyde-containing polymers, but is also a product of thermal-oxidative destruction of many other polymer materials, both artificial (for example, epoxy) and natural (rosin). Formaldehyde is found in the furniture and woodworking industries, where synthetic adhesive materials are used, in textile factories, released from urea-formaldehyde impregnant, in the production of press products from pheno- and aminoplast powders, in the mining industry and foundry industry, since formaldehyde resins are part of fasteners for rocks and molding soil.

Of particular importance in the development of occupational allergic diseases are the quality of chemical raw materials, its composition, including residual amounts of free and allergenic monomers or other ingredients that have not reacted during the synthesis process, which determine the allergenic activity of the composition as a whole. This situation can be confirmed by a higher level of allergic diseases during the introduction of new polymer materials into the technological process, such as, for example, synthetic formaldehyde-containing adhesives in furniture production. At the same time, subsequent improvement of raw materials taking into account hygiene requirements, in particular to a decrease in residual synthesis products in them, is accompanied by a decrease not only in occupational allergies, but also in numerous allergic complaints (so-called allergic manifestations).

In general, the danger of the sensitizing effect of industrial allergens increases significantly during the processing of chemical raw materials. Subsequently, at the stage of product manufacturing (at chemical industry enterprises), more high degree sealing of equipment and, more importantly, continuity technological process, and therefore the risk of allergenic effects is reduced. In other industries (in construction, rubber, woodworking, plastics, textiles, footwear and many others), numerous operations remain where workers have direct contact with relevant chemical factors. A clear example of this is pressing operations, which are quite common in industry. Even in cases where the temperature regime of such operations does not exceed the level at which products of tremoxidative destruction are formed, the impact on workers of migrating volatile components not only reaches significant intensity, but also has a pronounced and intermittent nature, since maximum gas emissions are observed during the opening of presses or other similar installations.

In addition to chemical compounds that have a sensitizing effect, organic allergens are also widespread in modern industry. As a rule, they are found in the environment much more often than chemical ones, but, being essentially household, they can cause occupational allergies. Thus, dust from flax, cotton, wool, silkworm cocoons, some types of wood, grain and flour dust, pollen of various plants, tobacco, essential oil crops, epidermal substances and many other natural allergens can be industrial not only for industrial workers (for example, in worsted -clothing, weaving and woodworking enterprises, in the public service sector), but also to no less extent for agricultural workers (among livestock breeders, poultry farm workers, plant breeders and other specialists). Significant chemicalization and the transfer of agricultural production to an industrial basis contribute to a change in the nature of industrial allergens in agriculture and, first of all, the combined action of organic allergens that have always been found in it with new chemical agents (pesticides, insectofungicides, new fertilizers, feed, etc.), many of which have quite pronounced allergenic activity. The rapid development of the microbiological industry, in particular associated with the ever-increasing need for high-calorie feed for livestock, as well as the chemical and pharmaceutical industry, causes a significant expansion of the sphere of influence of various producing fungi, microbial cultures, enzyme and hormonal drugs, vitamins and other biologically active substances.

The combined effect of both chemical and biological allergens on the body can most clearly be seen in the examples of the production of antibiotics and the entire chemical and pharmaceutical industry in general, where different stages technological process, along with biological and organic allergens, workers have contact with intermediate and final products chemical synthesis. The combination of organic, biological and chemical allergens occurs in worsted-cloth and weaving enterprises, where, along with cotton dust, wool, microbial factors (due to the contamination of raw materials with various microflora), chemical lubricants are used, some of which include triethanolamine, various dyes, in particular chromium-containing, synthetic impregnants, for example, urea-formaldehyde precondensate.

Textile factories and many other industries widely use various synthetic detergents, which even in conditions of domestic use can cause allergic dermatitis or bronchial asthma. In some cases, synthetic detergents, not being immediate cause allergic diseases, due to their potential sensitizing ability, can create a certain favorable immunological background for the action of other allergens, including industrial ones, and thus contribute to an increase in allergic morbidity. Many chemical compounds, which are not allergens, but causing development autoallergic reactions (for example, salts of certain heavy metals, peroxides, many solvents). In addition, even the irritating effect of chemical agents can promote more active conjugation of chemical allergens with body proteins and, consequently, a more intense antigenic (sensitizing) effect of the latter.

Modern industry and Agriculture characterized by complex (different routes of entry) and combined (different combinations) effects of allergens / which is important for understanding a number of features clinical course occupational allergic diseases and theirs; prevention. Thus, combined exposure to allergens can contribute to the development of polyvalent sensitization, although in early dates the formation of allergic reactions in their development, as a rule, is to blame for the most active allergen or the one acting in a higher dose compared to others. Therefore, an effective direction for the prevention of occupational allergies is the hygienic regulation of the composition of complex chemical products in order to reduce their sensitizing effect, as well as the regulation of industrial allergens in the air of the work area, taking into account the threshold of their allergenic effect.

The complex impact of allergens in production conditions largely determines the possibility of developing combined occupational allergic lesions, including the skin, respiratory system and gastrointestinal tract ( similar diseases occur, for example, when working with fiberglass lubricants). With occupational allergic lesions of chemical etiology, a combination of respiratory allergies, in particular bronchial asthma, and allergic dermatoses is quite often observed.

Occupational allergic diseases are characterized by a certain dependence of the development of one or another nosological form of allergosis on the intensity and duration of exposure to allergens. In people with short work experience, whose professional activities take place under conditions of exposure to relatively low doses of industrial allergens, allergic skin lesions (allergic contact dermatitis) are more common. At the same time, the development of occupational bronchial asthma is more common for workers with extensive work experience. This pattern in the development of these nosological forms of allergosis is most likely due to the characteristics of the body’s immune system, which is characterized by an earlier response of the cellular immune system, ahead of the processes of specific antibody formation.

Despite the abundance of allergens of various natures in the environment, and even more so in the industrial environment, the normal functioning of the immune system fully ensures the body’s protective reaction and prevents the development of allergic diseases, since the main function of the immune system, which is under strict genetic control, is aimed at recognizing “one’s own” " and "foreign", binding the latter and its elimination from the body. With normal functioning of the immune system, the reaction to the allergen, i.e. sensitization, is not accompanied by health problems and has a protective, adaptive nature. Most healthy individuals sensitization over time transforms into immunological tolerance (unresponsiveness), which eliminates the possibility of developing an allergic disease. However, the state of tolerance is not absolutely stable and can be interrupted as a result of neurohormonal crises, various pathological conditions, physiological stress, as well as due to the cumulative effect of industrial allergens or any significant changes in the working environment. This leads to dysregulation of immune mechanisms and, as a result, to activation of the immune response to the allergen and autoallergens. The resulting cytotropic antibodies, cytotoxic immune complexes and effector lymphocytes damage cells and tissues, resulting in the development of pathochemical and then pathophysiological reactions, manifested in the form of various symptom complexes of an allergic disease. And the development of one or another nosological form of allergosis, despite the fact that its formation occurs with the participation of both cellular and humoral immune mechanisms, is most likely associated with more pronounced violation one of the immune systems: predominantly cellular - for allergic dermatoses and humoral - for respiratory allergies. In addition, a predisposing factor for the development of a certain nosological form of allergosis may be a disease of one or another organ or system of the body, occurring with a violation of the local
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