Allergens and allergic occupational diseases
Occupational Diseases / / August 12, 2017
allergens (antigens) - a substance capable of affecting the immune system and generate immune response in the form of allergic reactions.Allergens can be foreign substances of protein origin (virus, bacteria, proteins, food and others.) Autoantigens (self proteins that result from various injuries become foreign to the body properties), various inorganic and organic substances, called haptens, are capable of solidly connectedin the body to a carrier protein and antigens become complex and toxic substances, which action causes the body's true autoantigens.Strong industrial chemical allergens are many aromatic amines, nitro- and nitroso compounds, oxides and organic peroxide, formaldehyde and antibiotics, mercury, arsenic, nickel, chromium, beryllium and others.
Immunopathogenesis chemical allergies largely unclear aetiology.It is believed that occurs upon exposure to the allergen reaction (sensitization) initially has a protective character.Specific antibodies bind to the allergen, and formed immune co
exogenous chemical allergy can occur as a reaction of immediate type (asthma, urticaria, angioedema, conjunctivitis, rhinitis) - manifestation of humoral forms of reaction, or delayed-type reaction in which dominates cellular immunity (dermatitis, eczema);often occurs mixed type of immune response.
form Humoral immune response characteristic of inhalation exposure proteins, allergens, with free circulation of complex antigens.In formulating skin test reaction develops after a few minutes (redness, swelling, blister).
delayed-type hypersensitivity (DTH) often develops under the action of microorganisms and chemical allergens.It is characterized by inflammation and the development of hyperergic manifested in the form of eczema, dermatitis or granulomatosis, for example in the lungs when berylliosis.In response to DTH skin test usually develops 24-48 hours (congestion, lymphoid infiltration).
In a production environment the clinical manifestations of allergies to a certain extent depend on the way the allergen receipt.Thus, pharmaceutical enterprises in workers exposed to dust antibiotics often develop asthma, urticaria;when working with solutions of penicillin - eczema, dermatitis.
In the event of allergies, in addition to the etiological factor of great importance is the state of reactivity;occupational allergies occur more frequently in individuals with burdened allergic heredity, as well as on the background of neuroendocrine diseases..
Lay allergies microbial origin or caused by food or other allergens predispose to the sensitizing effect, even weak industrial allergens.On the other hand, chemical allergies etiology, even asymptomatic, can increase the sensitivity to other (bacterial, food) allergens.
For chemical allergies are characterized by frequency or group of cross-allergies.Thus, during sensitization Ursol positive allergic tests also fall on aniline and some aromatic nitro and nitroso compounds (probably due to the formation, in the body similar metabolites).Increased sensitivity to nickel makes contact with potentially dangerous cobalt, and vice versa.
At simultaneous or sequential exposure to several allergens may be a competitive relationship.At the same time a strong allergen is able to suppress the immune response to a weaker or strengthen it.
Modern classification of allergies is complex.It involves determining the etiology: infectious (bacterial, viral, fungal, parasitic) or non-infectious (chemical, pollen, dust);pathogenic form (ekzoallergicheskaya, autoimmune, mixed);pathogenetic step (monoallergii - monovalent sensitization or poliallergii - polyvalent sensitization);clinical stage.This makes it possible to formulate a detailed clinical and nosological etiological, pathogenetic, functional diagnosis.In justifying the diagnosis of occupational allergosis should consider: occupational history, allergic history (for example, the question about the changes in health status during the interruption - holidays, weekends, and the resumption of work - "the elimination of the symptom" and "exposition" or "reekspozitsiozny" test);the results of specific allergy testing in vitro and (or) in vivo (in biological media definition of immune response cells, the predominance of eosinophils, lymphocytes, sensitization establishing etiology and localization allergosis by applying test allergen provocation tests and local).
Treatment Treatment of allergic diseases is complex.First, you need to stop contact with the allergen.Anti-allergic drugs mechanism of action can be divided into two groups: desensitizing and influencing the expression and the allergic reactions.The most effective is the implementation of specific desensitization.This is possible, when it turned out the allergen.Usually performed subcutaneous or intramuscular injection preparations allergen "in gradually increasing amounts.
If the allergen is not installed or for specific desensitization can not be achieved due to the high toxicity of the allergen, apply the so-called non-specific desensitizing agents.For desensitization nonspecific protein drugs are generally administered (plasmon et al.) In gradually increasing doses and sulfur preparations, aloe neobenzinoly.
Among the substances that influence directly on allergic manifestations of the disease, a large group consists of antihistamines - Promethazine (pipolfen), diphenhydramine, suprastin widely used for the treatment of urticaria, vasomotor rhinitis, itching dermatoses, acute allergic conjunctivitis and iridocyclitis, kapillyarotoksikoz.Antiallergic effect also exhibit some drugs affecting acetylcholine activity in vivo (atropine and a number of other M-holinolitticheskih means).
For the treatment of allergic diseases are also used means weakening the inflammatory process components: sodium thiosulfate, cysteine and other sulfur-containing compounds, prednisolone, adrenocorticotropic hormone and other
30 Dec, 2017
30 Dec, 2017