Analytics: Allergic occupational diseases of workers. Occupational allergic diseases of healthcare workers
The prevalence and properties of metals
We have to deal with metals on a daily basis: doorknobs, coins, cutlery, crockery and jewelry. Metals are mostly toxic than allergens. To take at least one of the most striking examples - mercury. Everyone knows that if you break a thermometer, then the mercury balls instantly scatter, clog into cracks, into the pile of the carpet and begin to emit toxic fumes. Since mercury is a cumulative poison, that is, it has the ability to accumulate in the body, its toxic fumes are deadly. However, the danger allergies in the form, in the worst case, bronchial asthma, in direct contact with one or another metal, also exists (4.5).
— simple substances, characterized by high thermal and electrical conductivity, plasticity, they are characterized by a peculiar metallic luster and opacity.
More than half of the chemical elements are metals: iron, copper, aluminum, tin, lead, chromium, molybdenum and others. However, in its pure form, metals are usually not used, with the exception of rare cases: in the manufacture of copper wires or aluminum utensils. Most metals are soft, easily deformed and quickly oxidized in air, so they are almost always used in the form of alloys - mixtures of various metals with each other and with non-metals.
metal alloys is a common cause of allergic contact dermatitis. Alloys causing allergy, most often contain nickel, chromium or cobalt - the most popular metal allergens.
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Metal |
Special purpose |
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Paints, decorative cosmetics, in the manufacture of insulin |
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Coins, accessories for clothing, furniture and interior items, bijouterie, products medical purpose: orthopedic and, needles, suture staples, as well as in the production of batteries |
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Compositions for tanning leather, pigments and paints, chrome plating of other metal products in order to give them decorative and anti-corrosion properties |
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Filling material, cement mixes (zinc phosphate cement) |
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Dental amalgams, vaccines, ophthalmic, ear drops and others medicines, thermometers |
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Jewelry, accessories |
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Platinum group metals (platinoids) |
Dental and other medical alloys, jewelry, accessories |
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Aluminum |
Antiperspirants, vaccines, dishes |
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Beryllium |
Dental implants |
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Coins, household items, medical and jewelry alloys, wires |
And these are far from all examples of the use of metals in Everyday life.
Allergic diseases caused by metals
When nickel is ingested in the composition of food products, a systemic contact dermatitis , the manifestations of which are described as "baboon syndrome": occurrence, areas of the buttocks.
Nickel is found in significant amounts in cocoa, tea, coffee, milk,, , peas, , herring, potatoes, asparagus, , beer, nuts, mushrooms, orange juice, and a number of other products. With the exclusion of these products from the diet, the cure is faster, however, nickel is a vital trace element that is part of a number of protein enzymes, so it complete removal from the diet is undesirable (2).
Allergic reaction to nickel is more common than, for example, cobalt, but often they are combined with each other: 25% of those suffering from nickel dermatitis have a history of allergy to cobalt. When these two allergies coincide, contact dermatitis (eczema) is much more severe.
The European Union has developed recommendations that take into account the needs of those suffering contact allergy for nickel. They prescribe both the reduction of the nickel content in various household products, and its exclusion from decorative products, as well as dietary recommendations.
Cobalt
A trace element necessary for the body, as it is part of B12 (cyanocobalamin), which ensures the formation of new red blood cells in the bone marrow. Deficiency of this vitamin leads to the development of megaloblastic anemia. A person receives it with food in the form of salts and compounds with organic substances.
Of the products in which cobalt is present, eyeshadows should be especially noted, since sweating is higher in the area of the folds of the eyelids, respectively, favorable conditions are created for the absorption of cobalt into the skin and the development of contact dermatitis.
Other household sources of cobalt are stainless steels, paints, and cement. Back in the 40s of the last century, the Italian dermatologist Fabio Meneghini pointed out the possibility skin sensitization masons to cobalt and chromium, the occurrence of contact allergic dermatitis, later called cement eczema (1,2,5).
Allergy to cobalt can manifest itself both locally - by direct contact with the metal and its alloys, and systemically - by inhalation of metal dust or eating foods rich in cobalt: legumes (peas, beans), garlic, liver (1).
Chromium
In the human body, chromium is involved in glucose metabolism, lipid and nucleic acid metabolism. At chromium deficiency there is a decrease in immunity, an increase in blood glucose levels. Acute deficiency chromium develops only with prolonged parenteral nutrition. Chronic insufficiency, according to some data, is inherent in at least 20% of the population.
Chromium is rich in liver, cheese, brewer's yeast, pomegranates, potatoes, tomatoes, spinach. It is a component of chromium picolinate, a substance used in dietary supplements.
In the human intestine, chromium can only be absorbed in the form of its salts with nicotinic acid and in the form of picolinate. Because a nicotinic acid- a very unstable compound, then long-term storage of products rich in it reduces its content. Chromium absorption also decreases with frequent consumption of fatty foods.
Of everyday items, chromium is found in the composition of anti-corrosion and chrome coatings, paints and cement, stainless alloys, and leather tanning compounds. Regular use of the above or constant contact with these substances in the workplace leads to the development of allergic contact dermatitis.
A systemic contact allergy to chromium compounds that are ingested with food will appear only if there has previously been direct contact with chromium, in connection with which hypersensitivity to this allergen has formed. The same can be said about other metals.
System contact allergic to chromium can develop when working with it (at work), in the presence of chromium-containing implants in the body (rarely), when using dietary supplements containing chromium, against the background of contact dermatitis to it (1.5).
Zinc
Zinc is a part of many proteins-enzymes that provide the most important biochemical processes in the body. Corn and - the products richest in it, in addition, it is in egg whites, beef liver, oatmeal.
Contact zinc dermatitis most often develops when it enters the body from the compositions. Cases of eczematous dermatitis around the mouth, maculopapular rash, palmoplantar pustulosis (formation of numerous vesicles) and other skin rashes after the installation of a dental filling based on zinc compounds are known. Inflammation disappeared after replacement with zinc-free fillings (1,4,5).
Mercury
Mercury is a strong allergen, and in addition, it is extremely toxic.
In its pure form, mercury is found, perhaps, only in a thermometer. Much more often, its mixtures with other substances (amalgams) or organic compounds are used.
Sources of inorganic mercury are amalgams used in dentistry, and organic sources are some preservatives, in particular, thiomersal (merthiolate). Skin rashes with mercury contact allergic dermatitis caused by dental materials are located in the mouth, face, neck. The affected areas are edematous, severe itching is characteristic. An eczema-like lesion may be oral cavity, where, in fact, the absorption of mercury from filling materials occurs.
When placing mercury-containing fillings, those who are hypersensitive to mercury may develop lichen-like rashes around the mouth, orofacial granulomatosis.
Thiomersal- This organic compound mercury, one of the five most common sources of contact allergens. It is widely used as a preservative in various pharmacological preparations (, external agents, ear and eye drops), cosmetics.
In some Eastern countries cosmetic products that whiten the skin, as well as mercury-based drugs that disinfect the skin, are popular. For example, in Taiwan or Indonesia, cases of severe contact dermatitis in young women after regular use of such drugs. At the same time, they found elevated levels mercury not only in the skin, but also in the blood.
Mercury can also be found in some pigments used for tattooing, and those who have pierced earlobes at the same time as having a tattoo are more likely to develop contact dermatitis to mercury (1,5).
Gold
Gold can be called one of the most common causes allergic contact dermatitis. Increased sensitivity to gold detected in a proportion of individuals with confirmed contact dermatitis. Moreover, with skin testing, sensitivity to gold salts is more often detected than to gold as such.
Despite the fact that gold dissolves very poorly, thanks to other metals in jewelry alloys, the release of gold ions occurs in enough for occurrence. In this case, dermatitis can manifest itself not only in places of direct contact with gold jewelry (earlobes, neck, fingers), but also, for example, on the skin of the eyelids. After some time, after the cessation of wearing gold jewelry, the dermatitis disappears.
Hypersensitivity to gold is more common in women than in men. This is understandable, since gold jewelry is worn mainly by women.
For golden contact dermatitis characterized by eczema in the head and neck. If you take a biopsy of the area of the skin that has often been in contact with gold jewelry, then metallic gold can be found in it. Moreover, its absorption into the skin is possible even through the intact stratum corneum (1).
Platinum group metals (platinoids): platinum, palladium, rhodium, iridium
Platinum and related metals are rarely used in the manufacture of household items due to their high cost, but can be found in dental implants and jewelry. Cases of contact dermatitis have been described when wearing platinum wedding rings.
Following the European Union directive to reduce the use of nickel in household and medical devices palladium has been increasingly used to replace it, leading to an increase in cases of allergic contact dermatitis to this metal.
Palladium present in dental implants can cause stomatitis, mucositis (inflammation of the mucous membrane), oral scaly rashes.
Hypersensitivity to rhodium and iridium is extremely rare. It is usually discovered incidentally during examination. large groups people suffering contact dermatitis to metals. At the same time, allergy to iridium and rhodium is combined with allergy to other metals and is not found in isolated form (1).
Aluminum
Contact hypersensitivity to aluminum is a rarity. Most often, its causes are the regular use of deodorant-antiperspirants and the introduction of vaccines or other pharmaceuticals containing aluminum compounds.
Aluminum contact dermatitis is characterized by relapsing eczema(for skin application) and persistent granuloma at the injection site. Cases of itching dermatitis in the armpit are described with the abuse of antiperspirants, with local treatment of skin diseases with a paste containing aluminum compounds.
Aluminum can be found in pigments used in tattooing. With sensitization to this metal in the area of the tattoo develops granulomatous reaction- formation in the skin of small nodules consisting of lymphocytes (1).
Beryllium
By itself, beryllium is poisonous and is used primarily in the aerospace industry and for the manufacture of special purpose alloys, such as springs that withstand increased amount load cycles. In everyday life, beryllium can be found only in the composition of dental alloys. Five different contact reactions to beryllium have been described: allergic contact dermatitis, toxic contact dermatitis, chemical burn, ulcerative granulomatosis, and allergic cutaneous granulomatosis (1).
Copper is widely used in alloys for coins, jewelry, household products, accessories, dental and other medical products, intrauterine devices. The most common cause of copper allergy is dentures and amalgams, intrauterine devices containing copper components.
In the first case, contact dermatitis on copper manifests itself as gingivitis, stomatitis, perioral allergic rashes. When installing intrauterine device with copper parts, dermatitis is systemic in nature and can be located in any area of the body in the form of an urticarial rash, swelling of the eyelids, swelling of the large and small labia. Symptoms of contact dermatitis may appear cyclically, depending on the phase of the menstrual cycle (1).
Diagnosis of Allergy to Metals
Most effective method diagnosis of contact allergy to metals - carrying out A test with the activation of lymphocytes is also used.
There are attempts to assess the levels of various cytokines when stimulating blood cells with metals in vitro (1,2,6).
K. Wolf R. Johnson D. Surmond Dermatology according to Thomas Fitzpatrick atlas - reference book "Practice" Moscow 2007 pp. 58 - 73
Shuvatova E.V. Clinical and immunological characteristics of the personnel of the Mining and Chemical Plant of the Krasnoyarsk Territory and the population living near the production. dis. cand. honey. Sciences State science Center Russian Federation Institute of Immunology FU "Medical - Biological and Extreme Problems" under the Ministry of Health of Russia Moscow 2004. pp. 11 - 28
Vasiliev A.A. Seasonal and age changes immune status personnel of the Mining and Chemical Combine of the Krasnoyarsk Territory dis. cand. honey. Sciences Federal State State-financed organization State Scientific Center of the Russian Federation Institute of Immunology of the Federal Medical and Biological Agency of Russia Moscow 2009. pp. 27 - 36
J. Bourke, I. Coulson, J. English Guidelines for the Management of Contact Dermatitis: an Update" The British Journal of Dermatology. 2009;160(5):946 - 954
Food allergy refers to hypersensitivity immune system to certain foods. The WHO has already called allergies the "disease of the century" because Today, the percentage of the population sensitive to one or more allergens approaches 50%. Milknews found out how the presence of allergens in food products is regulated, what “may contain traces” means, and how manufacturers deal with allergen-containing products.
How it works?
About 120 food allergens enter the human body every day.
The main food allergen is cow's milk, an allergy to it develops from the first year of life. Vera Revyakina, Head of the Allergology Department of the Federal State Budgetary Institution “Federal Research Center for Nutrition and Biotechnology”, noted that among children under one year old, milk remains the leading cause allergic reactions- more than 80% of detections are associated with casein and whey proteins. An allergy to cheese occurs in about 12% of people with food allergies - this is due to high content histamine.
In general, the greatest allergenic activity is manifested from products of plant origin - cereals with gluten (rye, barley), nuts and products of their processing cause up to 90% of all cases of food allergies, and therefore there is a whole list in the Technical Regulations of the Customs Union 022/2011 from the main allergens.
Food allergies affect people of all ages, starting from infancy, the reaction of the body can develop both in a few minutes, and for several hours or even every other day. Symptoms can also range from completely unnoticeable external manifestations up to anaphylactic shock - a fatal reaction manifested in a weakening of breathing, a decrease in pressure and a violation heart rate with the possibility of death.
Among the allergens are major, medium and small. Main allergen binds about 50% of antibodies in the blood serum of a person who is sensitive to this allergen, minor - about 10%.
IN Food Industry during the processing of products, the antigenic properties change, heating, for example, leads to protein denaturation. At the same time, if some products may become less allergenic after heat treatment, others may become more dangerous. Thus, the thermal denaturation of cow's milk does not lead to the loss of the allergenic properties of proteins, but in some cases it is better to boil the milk in case of allergies (this is advised only for those who are sensitive to thermolabile protein fractions). The peanut allergen, for example, is almost not destroyed by any processing - allergy sufferers should be aware of this, especially given the widespread use of peanuts in the food industry. The allergenic properties of fish also change during processing, therefore, with intolerance to freshly prepared fish, some patients may eat canned fish.
The only true way to prevent food allergies is the complete elimination of allergens from the diet, but here, too, everything is not so simple. If you think that you can simply eliminate them from your diet with a nut allergy, then no, you will not be 100% safe. Even in products that do not contain any allergens in their composition, their residues (i.e., traces) may appear in them, simply because other products were packed on the conveyor before.
There is no exact answer to the question of whether the consumer should be afraid of the indicated data on traces of allergens - of course, it all depends on individual sensitivity.
Manufacturer regulation
In accordance with Technical Regulation 022, today allergens include 15 types of components:
- peanuts and products of its processing;
- aspartame and aspartame-acesulfame salt;
- mustard and products of its processing;
- sulfur dioxide and sulfites, if any general content is more than 10 milligrams per kilogram or 10 milligrams per liter in terms of sulfur dioxide;
- cereals containing gluten and products of their processing;
- sesame and products of its processing;
- lupine and products of its processing;
- shellfish and products of their processing;
- milk and products of its processing (including lactose);
- nuts and products of their processing;
- crustaceans and products of their processing;
- fish and products of its processing (except for fish gelatin used as a base in preparations containing vitamins and carotenoids);
- celery and products of its processing;
- soy and products of its processing;
- eggs and products of their processing.
If the manufacturer does not indicate in the composition that the product may contain residues of allergic agents, he is liable under the Code of Administrative Offenses 14.43 part 1 (violation of the requirements of technical regulations) and part 2 (if the violation caused harm to life and health), which provide for a fine from 300 to 600 thousand rubles for legal entities, a repeated violation entails a fine of up to 1 million rubles. Also, the manufacturer can be brought to 238 article of the Criminal Code of the Russian Federation “Production, storage, transportation or sale of goods and products that do not meet safety requirements” with possible limitation freedom up to two years, if unsafe products caused serious harm to health or death of a person - up to six years, if two or more - up to ten years in prison.
Only technological aids, which are understood as substances or materials or their derivatives (with the exception of equipment, packaging materials, products and utensils), which, not being components of food products, are deliberately used in the processing and production of food products to perform certain technological goals and after their achievement are removed from such raw materials. Technology groups aids established in the technical regulation of the Customs Union 029/2012 "Safety requirements for food additives, flavors and technological aids" (catalysts, solvents, etc.).
A conscientious manufacturer strives to ensure that allergens do not intersect in production, but sometimes it is not possible to exclude the presence of traces from other raw materials, even if a full set of measures is taken to clean and disinfect equipment.
On the conveyor
Most often, the problem of trace contamination occurs in the pharmaceutical and food industries. From the food industry, mainly to meat processing, because components like soy, mustard, sesame and gluten are often used in manufactured products. Technical regulation 022/2011 establishes that components that can cause allergic reactions must be indicated in the composition, regardless of their quantity. Even if allergen-containing products were not intentionally used in production, but their presence cannot be completely excluded, information about their possible presence should also be placed on the packaging. This is necessary to timely inform consumers that even in products that do not contain food allergens their remnants may remain.
To minimize the inadvertent entry of allergens into food, food companies are developing whole complex activities within the so-called. allergen management programs. The introduction of such a system is included in the food safety management system.
To get started in this direction the manufacturer analyzes the total number of allergens that can cause a reaction in sensitive people, as well as identifying special populations that are at particular risk, and only after determining the “target audience” among consumers, the allergens themselves are studied.
The allergenicity of the ingredients used is examined as well as their “behavior” - for example, if the product has been processed, it may lack the corresponding protein, and therefore the product may not be dangerous due to the lack of risk of allergen cross-contamination.
After that, the probability of cross-contamination with allergens at each stage of food production is assessed, here it must be taken into account that it is different for liquids and powder. Powdered milk during weighing can get into products by by air- through the ventilation system or through the clothing of personnel, but with liquid milk everything is easier - if the distance and isolation by physical barriers are observed, the probability of its getting into products is close to zero.
If, nevertheless, the risk of contamination was assessed as unacceptable, the enterprise takes a number of measures aimed at reducing the unintentional ingress of allergens into products. As part of the organization of the production process, the GMP standard (English Good Manufacturing Practice, good manufacturing practice) is used - this is a set of rules that establish requirements for the organization of production and quality control.
The manufacturer must be aware of the presence of allergens in all raw materials used in production, as well as in raw materials that are achieved during work with the supplier and during incoming control. The manufacturer must request from suppliers all information on the content of food allergens in raw materials, whether it is one of the main components indicated in the composition (for example, vegetable protein soy in a complex food additive), an auxiliary component (a food additive derived from an allergenic source), or undeclared components that entered the product due to industrial cross-contamination with allergens.
Suppliers, in turn, need to be aware of the risks posed by cross-contamination, they must fully describe all components in the labeling, generic names of ingredients cannot be used. After incoming control and placement in warehouses, it is necessary to identify all allergen-containing raw materials, it is advisable to store them separately.
Of course, the only way to avoid cross-contamination is to use different production sites - separate for each product, which is most often not possible, however, there are ways to minimize the possibility of contamination, for example, dividing production into zones, using separate equipment and planning production cycles. Need to take care of complete cleaning equipment between cycles, organizing a separate air supply if possible, and working with staff - humans are also potential carriers of food allergens.
If produced New Product or a new ingredient is introduced, the manufacturer must be aware that this may introduce allergens into all existing products, so a full risk assessment should be carried out before doing so.
Industrial allergens
The rapid development of the chemical industry has significantly increased the amount of various chemicals in production and at home, and therefore, people's contact with them. This caused the appearance of allergic reactions of various nature. Industrial allergens are overwhelmingly haptens, which bind to proteins through their reactive group. For example, through the halogen atom, aromatic nitro compounds are attached, the mercapto groups of a number of pesticides react with the HS groups of proteins, etc. It is believed that the higher the ability of the hapten to form a chemical bond with the 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, allergens can be 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 cause a variety of pathogens of infectious diseases, as well as their metabolic products. These processes become integral part the pathogenesis of the disease. Those infectious diseases, in the pathogenesis of which allergy plays a leading role, are called infectious-allergic diseases. They include all chronic infections(tuberculosis, leprosy, brucellosis, syphilis, rheumatism, chronic candidiasis, etc.). With the elimination of epidemic diseases, allergic processes, which are caused by opportunistic and saprophytic flora, have become increasingly important. The source of sensitization is usually the flora of chronic foci of inflammation in the paranasal sinuses, middle ear, tonsils, carious teeth, gallbladder, etc. In this case, some forms of bronchial asthma, angioedema, urticaria, rheumatism, ulcerative colitis and other diseases can develop. Mushrooms are very common allergens. About 350 species of mushrooms show allergenic activity. Among them, there are species pathogenic for humans that cause diseases with allergies at the basis of pathogenesis. Such diseases are, for example, aspergillosis, actinomycosis, coccidioidomycosis, 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.). Such fungi are found in the atmospheric air, dwellings, house dust, moldy foods, etc. Their concentration depends on the season, 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 reaction of the immediate type 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).
Pseudo-allergy is a pathological process that is clinically similar to 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 - the release of mediators (pathochemical) and pathophysiological (the stage of clinical manifestations) coincide with pseudo-allergy and true allergy.
Pseudo-allergic processes include only those in the development of which such mediators play a leading role, which are also formed in the pathochemical stage of true allergic reactions. The cause of pseudo-allergy is any substance that acts directly on effector cells (mast cells, basophils, etc.) or biological fluids and causes the release of mediators from cells or the formation of mediators in fluids. In practice, most allergens can lead to the development of both allergic and pseudo-allergic reactions. It depends on the nature of the substance, its phase, the frequency of introduction into the organism and the reactivity of the organism itself. Pseudo-allergic reactions are most common with drug and food intolerance. Very many drugs lead to the development of pseudo-allergies more often than allergies.
Three groups of mechanisms are involved in the pathogenesis of pseudoallergy:
- 1) histamine;
- 2) violation of the activation of the complement system;
- 3) a violation of the metabolism of arachidonic acid.
The clinical picture of pseudo-allergic diseases is close to that of allergic diseases. It is based on the development of such pathological processes as increased vascular permeability, edema, inflammation, spasm smooth muscle, destruction of blood cells. These processes can be local, organ, systemic. They are manifested by rhinitis, urticaria, angioedema, recurrent headaches, disorders of the 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 the allergen.
- Type 2 hypersensitivity due to the cytotoxic effect of antibodies involving complement or effector cells.
- 3rd type - immunocomplex reaction. Due to the pro-inflammatory action 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.
To date, some experts distinguish the 5th type - receptor-mediated.
1. type - anaphylactic,……… classic allergic reaction of immediate type.
Ingestion of an antigen 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 content of IgE in secrets is higher than in blood serum (especially a lot of it in colostrum). Most IgE is secreted by mucosal lymphoid cells. Whey
IgE has a short lifespan - 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 mucous membranes. The development of mast cells, in addition to the main factor SCF, 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
Several processes underlie the local manifestations of allergies.
Local vasodilation. It manifests itself quickly and is due to the action of histamine and other preformed factors, a little later - eicosanoids (especially LTC4). Visible manifestation is redness. Increased vascular permeability. Its cause is vasoconstriction by histamine, leukotrienes, and platelet aggregation factor (PAF). Leads to the development of edema, promotes extravasation of blood cells. Local violation permeability with the formation of leukocyte exudates and hemorrhages is the basis of skin rashes. The accumulation of fluid in the subepidermal space is the morphological basis of blisters. Spasm of smooth muscles, especially bronchi. Spasm is caused by eicosanoids (lecotriens C4 and D4, prostaglandin D2, PAF), to a lesser extent histamine. The manifestation is an asthmatic attack (an attack of bronchospasm). Hyperproduction of mucus (nasal, bronchial) and other secrets (for example, tears). Called leukotrienes. It accompanies bronchospasm or serves as an independent manifestation of an allergic reaction. Similar phenomena in the intestines cause diarrhea. Irritation nerve endings leading to itching and pain.
Cytotoxic type of hypersensitivity (type II hypersensitivity) Type II hypersensitivity refers to pathological processes, which 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 cause 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 newborns. The immunological bases of hemolysis caused by incompatibility in blood groups AB0 are discussed above. They are associated with the preexistence of antibodies to the missing group antigens. That is why the transfusion of incompatible erythrocytes that bind to antibodies in the bloodstream leads to their mass lysis and the development of complications such as jaundice and tissue damage when complexes of erythrocyte membrane proteins with antibodies are deposited. Rh-conflict hemolytic anemia has a slightly different basis (Fig. 4.36). Among several antigens (C, D, E, c, d, e) of the Rh system, antigen D is the most powerful and is able to induce the production a large number antibodies. It encodes dominant gene D, the recessive allelic variant of which is gene d. Conflict situation, caused by incompatibility for these genes, does not appear during blood transfusions, but during pregnancy of an Rh-negative mother (with the dd genotype) with an Rh-positive fetus (DD and Dd genotypes). During the first pregnancy, usually there are no violations of the immune nature in the body of the mother and fetus.
III type. When the system of elimination of immune complexes is damaged.
Normally, during the interaction of antigens coming from outside and the resulting antibodies, immune complexes, with which complement components are connected when it is activated along the classical path. way. The complexes interact with CR1 (CD35) receptors on erythrocytes. Such erythrocytes are engulfed by liver macrophages, which leads to the elimination of the complexes. When antibodies interact with antigens of the cell membrane of pathogens or other foreign cells, their opsonization occurs, which also contributes to the phagocytosis of these cells. 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 the antigen, as well as the accumulation of a large number of antibodies, the implementation of the processes described above is disrupted. The most important event in the development of immunocomplex pathology is the formation of insoluble immune complexes and their deposition in tissues. The transition to an insoluble state is promoted by an excess of antibodies or insufficiency of the complement system (complement binding 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 associated with the presence of Fc receptors on their surface. The deposition of complexes contributes to the development of inflammation. The role of inflammatory triggers in this case is played by small fragments of complement components C3a and C5a, which are formed during complement activation. The listed factors, also called anaphylotoxins, cause vascular changes characteristic of inflammation and attract neutrophils and monocytes to the place of deposition of complexes, causing their activation. Activated phagocytes secrete pro-inflammatory cytokines (IL-1, TNFb, IL-8, etc.), as well as cationic proteins, enzymes, and other active molecules, which leads to the development of a full-scale inflammatory response. Cell damage can also be caused by complement activation 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. Immunocomplex 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 of general symptoms with local inflammatory processes in places of deposition of complexes.
Autoimmune cytotoxic receptor-mediated pathology - this type, some authors refer to the 5-type.
Antibodies are produced that can bind to cell receptors, either activating their function or closing the receptor from bioactive substances.
So in type II diabetes mellitus, antibodies circulate that compete with insulin receptors, thereby closing them from insulin.
Delayed type hypersensitivity (type IV hypersensitivity)
Delayed-type hypersensitivity is the only type of hypersensitivity that is directly based on cellular rather than humoral mechanisms. Its prototype is the Mantoux reaction, the response of a sensitized organism to the intradermal administration of tuberculin. The delayed-type hypersensitivity reaction underlies one of two forms of 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 to inflammatory type with the formation of effector Th1 cells.
Due to the widespread introduction chemical technologies into production, the organization of factories producing protein concentrates and additives, the development of the pharmaceutical industry, etc. the number of patients suffering from allergic diseases associated with a particular production has increased. True, cases of the occurrence of bronchial asthma in flour millers, workers in fur and leather industries, and woodworking plants have long been known.
The influence of production conditions on the occurrence of the disease, the pathogenesis of the disease and its clinical picture in each individual case may be different, however, in each production, the development of an allergic disease has its own characteristics.
CONTACT DERMATITIS
Most often, dermatitis occurs in people working with formalin, chromium, mercury, turpentine, antibiotics, glue, dyes. The clinical course of contact dermatitis is characterized at the beginning of the disease by a lesion of the skin itself - hyperemia and edema. Later, symptoms of damage to deeper layers of the skin appear - bubbles form that burst, weeping yellow scabs appear, that is, eczematization occurs. With the appearance of large confluent blisters with a large zone of hyperemia, even burns of the I or II degree can be assumed.
In some people, dermatitis immediately takes on a papular-infiltrative character with severe itching, with sharply defined edges. IN chronic phase disease, the clinical picture is no different from non-professional contact dermatitis, it can only be the location, that is, damage to those areas of the skin that are exposed to aggressive hazards (hands, face and other exposed parts of the body). Often, such dermatitis is accompanied by damage to the mucous membranes of the eyes, nose, and oral cavity.
There are also edematous manifestations on the eyelids, dyshidrosis of the palms and soles. Features of occupational contact dermatitis are sudden onset and frequent recurrence upon resumption of work. In the future, due to constant itching, scratching, superinfection occur, and with continued exposure to the allergen, due to its spread through the affected skin by the lymphohematogenous route, symptoms may occur. general- fever, malaise, weakness, etc.
By clinical picture contact dermatitis, it is not always possible to resolve the issue of what allergen it is caused by, since allergens of different nature can cause the same clinical manifestations. Issues of etiological diagnosis in occupational dermatitis are very relevant, however skin tests in such patients, it is not always possible to carry out because of the danger of causing an exacerbation. The detection of antibodies is also not possible, since they do not have freely circulating antibodies, therefore a correctly collected anamnesis, data on the course of the disease and the presence of an elimination factor are sometimes decisive for a correct diagnosis.
The prognosis for occupational contact dermatitis is favorable - with timely diagnosis, elimination of occupational hazards (transfer to another job), proper treatment. True, often, despite all the measures, dermatitis, arising on the basis of occupational hazards, can continue and full recovery does not come. This indicates the existence of complicating factors (other chronic diseases, polyvalence, superinfection, improper treatment).
Prevention is based on general and personal means protection when working with industrial hazards. In addition to these measures, people with a predisposition to allergies, with skin dysfunction should be avoided working in chemically and biologically hazardous industries. Preliminary determination of the suitability of a given person for working with a particular substance is also desirable - conducting an appropriate test.
urticaria and erythema
Occupational urticaria is much less common. Causes of urticaria and erythema can be chemical, physical and biological.
Chemical causes most often cause urticaria and erythema in those associated with the pharmaceutical industry, nurses, and pharmacy workers. Known cases of urticaria on morphine, arnica, ipecac, mercury preparations, penicillin, novocaine, phenol, ammonia, as well as herbal remedies - thuja, rhododendron, nettle, tobacco and oils; for biological preparations - tetanus toxoid, influenza vaccines, etc.
Of the physical factors that cause urticaria and erythema, the action of high and low temperature should be mentioned. Workers in ceramic factories, steel-smelting shops often develop extensive erythema and urticaria on high temperature, and for traffic police officers - to low. Biological factors that cause urticaria and erythema include dust, animal hair (veterinarians), insect bites (lumberjacks, beekeepers), contact with fish, jellyfish (ichthyologists, fishermen), etc.
BRONCHIAL ASTHMA
Bronchial asthma associated with occupational hazards, is inhomogeneous. A. E. VERMEL (1966) distinguishes 3 groups of professional bronchial asthma:
- caused by substances-sensitizers (primary asthma);
- caused by substances that irritate the local respiratory tract, leading to chronic bronchitis and only then to bronchial asthma (secondary asthma);
- caused by sensitizers that simultaneously have a local irritant effect.
Occupational bronchial asthma occurs when inhaling dust, smoke, vapors various substances. Very rarely, bronchial asthma occurs when harmful substances enter through the gastrointestinal tract when tasting cheeses, coffee, tea, wines, etc.
Occupational bronchial asthma has some distinctive features depending on the nature of industrial hazards. IN different dates from the beginning of contact with industrial hazards, the first attack of bronchial asthma may occur.
Sometimes bronchial asthma occurs in people without any other manifestations of allergies, but more often it is combined with the presence of eczema, dermatitis, rhinitis, Quincke's edema, etc. Often the cause of bronchial asthma and other manifestations of allergies are the same occupational allergens.
Asthma attacks occur in different time, but more often at work, at the end of a shift, after some exposure to an industrial allergen.
At the beginning of the disease, the attacks of suffocation are not severe, they are removed if you leave the production room, but over time, the attacks become more severe, coughing attacks with thick, viscous sputum are disturbing. Later attacks are also caused by other factors, excitement, weather changes, etc.
In cases where occupational asthma occurs not as primary disease, and against the background of a chronic pathological process in the bronchopulmonary apparatus (silicosis, pneumoconiosis, bronchitis), the period before the development of typical attacks is quite long.
Asthmatic phenomena develop in such patients gradually, against the background of previous bronchitis, persistent cough. In cases of secondary asthma, it is difficult to establish a connection with occupational hazards, since attacks also occur outside of work, during vacations, etc. In these cases, the primary chemical or mechanical damage to the bronchial mucosa leads to the development of occupational bronchitis, on the basis of which bronchial asthma develops secondarily, often an infectious-allergic form.
EXOGENOUS ALLERGIC ALVEOLITIS
It is especially necessary to single out a group of diseases associated with damage lung tissue immune mechanisms under the influence of exogenous allergens - fungal spores, protein antigens. Since exogenous allergic alveolitis is associated with the inhalation of certain occupational allergens, they are named according to the profession, for example, "farmer's lung", "lung of furriers", "lung of coffee grinders", "lung of pigeon breeders", etc.
Currently, more than 20 professions are known in which exogenous alveolitis occurs, which are based on immunological mechanisms (the “allergen-antibody” reaction).
A feature of these mechanisms is the formation of precipitating antibodies, which, when combined with the allergen, form immune complexes that settle in the walls of the alveoli, small bronchi. Immune complex deposition is promoted by increased permeability vascular wall. During allergic exogenous alveolitis, all 3 types of allergic reactions are traced (see Chapter 2).
People who are predisposed to allergic reactions get sick with exogenous pulmonary alveolitis after prolonged contact with the allergen. The course of the disease can be acute, subacute and chronic. Sometimes alveolitis occurs intermittently in the form of acute outbreaks when inhaled large doses allergen (cleaning the dovecote, sorting rotten hay, working at the mill).
In the acute form, the disease is often interpreted as pneumonia, since there is an abundance of physical data (wet wheezing, small bubbling), increased ESR, leukocytosis.
In the course of the disease in the lung tissue occur irreversible changes associated with the formation of granulomas and scarring, which lead to the development of pulmonary fibrosis.
In the acute and subacute stages, the use of glucocorticoid hormones is indicated. Prevention consists in preventing contact of patients with the corresponding allergen (change of profession). Chronic form exogenous allergic alveolitis is difficult to treat, symptomatic therapy is usually carried out.
Combining various nosological forms of occupational allergic diseases in a special section is due to the fact that they all represent one of the manifestations of impaired immunity, clinically occurring in the form of various symptom complexes of an allergic reaction. There is currently an increase in the incidence allergic nature. This is due to a significant change in the human immune system under the influence of numerous environmental factors, including chemical ones. These facts are even more important in the conditions of modern production, where there is a significant duration and intensity of their impact. It is characteristic that the increase in the number of cases of occupational allergic diseases occurs against the background of a decrease or more light flow occupational intoxication. 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 do not always ensure safety in relation to the development of allergic reactions, since the threshold doses of the so-called specific, including allergenic, action of many products are often significantly lower than the threshold toxic doses. .
Number of industrial allergens, which include natural and artificial chemical substances and compounds, organic products and biological substances with which significant contingents of people in various sectors of the national economy have contact, 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 make up 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, being released from them during processing and use.
A large group of complex allergenic products are 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 glass fibers), 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.
In cases of modern production, chemical allergens can affect the body of workers, being in various states of aggregation. So, in the mining industry, the danger of a sensitizing effect is mainly associated with dust containing various allergenic metals, and in steelmaking and electric welding works - in the form of condensation aerosols. Metal sensitizers pose a significant hazard when exposed to cement dust inhalation, which occurs at cement and asbestos-cement plants, but contact of the skin 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 captax, thiuram E, neozone D, triethanolamine are allergens , rosin and some others. Formaldehyde is found very 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 degradation of many other polymeric materials, both artificial (for example, epoxy) and natural (rosin). Formaldehyde is found in the furniture and woodworking industry, where synthetic adhesive materials are used, in textile enterprises, escaping from the urea-formaldehyde impregnant, in the production of press products from phenolic and aminoplast powders, in the mining industry and foundry, since formaldehyde resins are part of the fasteners for rocks and molding earth.
Of certain importance in the development of occupational allergic diseases are the quality of chemical raw materials, their 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 position can be confirmed by a higher level of allergic diseases during the introduction of new polymeric materials into the technological process, such as synthetic formaldehyde-containing adhesives in furniture production. At the same time, the subsequent improvement of raw materials, taking into account hygienic requirements, in particular, the reduction of residual synthesis products in them, is accompanied by a decrease not only in occupational allergies, but also in numerous allergic complaints (the so-called allergic manifestations).
In general, the danger of the sensitizing effect of industrial allergens increases significantly in the process of processing chemical raw materials. Subsequently, at the stage of manufacturing the product (in the chemical industry), a higher degree of sealing of the equipment is observed and, more importantly, the continuity of the technological process, and therefore the risk of allergenic effects is reduced. In other branches of industry (construction, rubber, woodworking, plastics, textiles, footwear, and many others), numerous operations are retained when workers have direct contact with the corresponding chemical factors. An illustrative example of this can serve as pressing operations, which are quite common in industry. Even in those cases when the temperature regime of such operations does not exceed the level at which products of tremooxidative degradation are formed, the effect of migrating volatile components on the working components not only reaches a significant intensity, but also has a pronounced and terminating character, since maximum gas emissions are noted during the opening of presses or other similar settings.
In addition to chemical compounds that have a sensitizing effect, in modern industry organic allergens are also widespread. As a rule, they are much more common than chemical ones in the environment, but, being essentially household, they can cause occupational allergies. Thus, the dust of 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 production not only for industrial workers (for example, worsted - cloth, weaving and woodworking enterprises, in the public service sector), but also to no lesser extent for agricultural workers (among livestock breeders, poultry farm workers, crop growers 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, to the combined action of allergens of organic nature that are always found in it with new chemical agents (pesticides, insectofungicides, new fertilizers, feed, etc.), many of which have a fairly 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 producer fungi, microbial cultures, enzyme and hormonal preparations, vitamins and other biologically active substances.
The combined effect on the body of workers of both chemical and biological allergens can be most clearly seen in the examples of the production of antibiotics and the entire chemical and pharmaceutical industry as a whole, where at different stages of the technological process, along with biological and organic allergens, workers have contact with intermediate and final products of chemical synthesis. The combination of organic, biological and chemical allergens takes place at worsted-clothing and weaving enterprises, where, along with dust from cotton, wool, microbial factors (due to contamination of raw materials various microflora) chemical lubricants are used, some of which include triethanolamine, various dyes, in particular chromium-containing, synthetic impregnants, for example, urea-formaldehyde precondensate.
At textile enterprises and in many other industries, various synthetic detergents, which even under conditions of domestic use can cause allergic dermatitis or bronchial asthma. In some cases, synthetic detergents, not being the direct cause of an allergic disease, 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. To a similar result, though based on a different mechanism of action, namely, denaturing the proteins of the skin and mucous membranes respiratory tract, can lead many chemical compounds, which are not allergens, but causing development autoallergic reactions (for example, salts of some heavy metals, peroxides, many solvents). In addition, even the irritating effect of chemical agents can contribute to a 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) exposure to allergens / which is important for understanding a number of features of the clinical course of occupational allergic diseases and them; prevention. Thus, the combined effect of allergens can contribute to the development of polyvalent sensitization, although in the early stages of the formation of allergic reactions in their development, as a rule, the most active allergen or the most active allergen is to blame compared to others in more high dose. Therefore, an effective way to prevent 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. working area taking into account the threshold of their allergenic action.
The complex exposure to allergens in production conditions largely determines the possibility of developing combined occupational allergic lesions, including the skin, respiratory organs and gastrointestinal tract (such diseases occur, for example, when working with fiberglass lubricants). In occupational allergic lesions of chemical etiology, a combination of allergosis of the respiratory organs, 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 allergy on the intensity and duration of exposure to allergens. In persons with little work experience, whose professional activity takes place under conditions of exposure to relatively low doses of industrial allergens, more often allergic lesions skin (allergic contact dermatitis). At the same time, the development of occupational bronchial asthma is more typical for workers with long work experience. Such a pattern in the development of these nosological forms of allergies is most likely due to the characteristics of the body's immune system, which is characterized by an earlier response. cell system immunity, advancing the processes of specific antibody formation.
Despite the abundance of allergens of various nature in the environment, and even more so in production, the normal functioning of the immune system fully ensures the protective reaction of the body and prevents the development of an allergic disease, since the main function of the immune system, which is under strict genetic control, is aimed at recognizing "its own "and" alien ", binding the latter and its elimination from the body. At normal functioning The reaction of the immune system to an allergen, i.e., sensitization, is not accompanied by a health disorder and has a protective, adaptive character. In most healthy individuals, sensitization eventually transforms into immunological tolerance (non-response), which excludes 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 occupational allergens or any significant changes in the occupational environment. This leads to dysregulation immune mechanisms and as a result, to the activation of the immune response to the allergen and self-allergens. 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 allergy, despite the fact that its formation proceeds with the participation of both cellular and humoral immune mechanisms, is most likely associated with a more pronounced violation of one of the immune systems: predominantly cellular - with allergic dermatosis and humoral - with respiratory allergies . In addition, a predisposing factor for the development of a certain nosological form of allergy may be a disease of one or another organ or system of the body, occurring with a violation of local
