Allergic diseases are a group of diseases caused by an individual’s hypersensitivity to certain foreign substances – allergens and occurring with the development of an IgE-mediated reaction of the immune system. The necessary conditions for the occurrence of allergies are high specificity (reaction strictly to certain antigens), sensitization (hypersensitivity to this allergen) and repeated exposure of the allergen to the body.
The term “allergy”, meaning “response, reaction to someone else” in Greek, was proposed by the Austrian pediatrician K. von Pirke in 1906. Over the past century, allergic diseases have acquired epidemic proportions, and the prevalence of allergies among adults and children continues to increase steadily. According to research, 35% of residents suffer from various allergic diseases in Western countries, in USA – from 17.5% to 30% of the population. These circumstances led to the allocation of a special medical discipline – allergology, which deals with the study of diseases associated with hypersensitivity reactions. The most common allergic diseases include allergic rhinitis, bronchial asthma, urticaria, atopic dermatitis.
The ethological classification of allergic diseases is based on the isolation of a causally significant allergen; within it, food, household, insect, medicinal, and infectious allergies are differentiated. According to the method of penetration into the body, aeroallergens, contact, oral, injectable allergens are distinguished. Taking into account the conditions in which an allergic reaction has developed, domestic, professional, seasonal allergies are distinguished. Depending on the predominant lesion of a particular organ system, the following groups of allergic diseases are distinguished: allergodermatoses (atopic dermatitis, eczema, urticaria, etc.), intestinal allergoses (allergic enterocolitis), respiratory (allergic rhinitis, allergic tracheobronchitis, bronchial asthma), acute allergic reactions (Quincke’s edema, anaphylactic shock).
The symptoms of various allergic diseases are caused by common pathogenetic mechanisms: the release of mast cell mediators and basophils into the tissues or into the blood, which cause characteristic vascular and smooth muscle reactions: edema, hyperemia, itching, hypotension, difficulty breathing.
In this case, the specific form of allergy depends on which organ or tissue the allergen comes into contact with immunoglobulin E, fixed on the cell surface. If this happens in the respiratory tract, a clinic of allergic rhinitis or bronchial asthma may develop, allergic conjunctivitis in the conjunctiva of the eye, urticaria in the surface layers of the dermis, Quincke’s edema in the subcutaneous tissue, etc. Since allergic diseases have extremely diverse manifestations, allergists work closely with dermatologists, pulmonologists, otolaryngologists, gastroenterologists, ophthalmologists, nutritionists and doctors other specialties.
The specific diagnosis of allergic diseases consists in collecting an allergological history, conducting allergy testing (allergy tests and provocative tests), determining general and allergen-specific IgE, if necessary, performing functional studies (spirometry with samples, peak flowmetry). After identifying the causal allergen, it is necessary to take immediate measures to eliminate it, i.e. completely exclude contact with the substance that provokes an allergic disease.
To this end, it may be necessary to change eating habits, abandon the use of certain cosmetics, get rid of upholstered furniture and carpets in the house, stop taking certain medications, change the scope of professional activity, etc. Modern principles of treatment of allergic diseases provide for specific hyposensitization (ASIT) by introducing allergens into the body in gradually increasing doses. After a full course of ASIT, persistent remission can be achieved in 70-80% of cases. Various groups of drugs are used for non-specific therapy of allergic diseases: antihistamines, cromons, corticosteroids, bronchodilators, etc. From non-drug methods, acupuncture, climatotherapy, homeopathy, phytotherapy are used.
The section “Allergic diseases” of this medical handbook provides information on the most common violations of immunological reactivity. These materials competently tell about modern views on the causes and features of the course of allergic diseases, as well as approaches to their diagnosis and treatment
Dust allergy is an allergic reaction that occurs upon contact with components of street or house dust and manifests itself in the development of symptoms of rhinitis, conjunctivitis, atopic dermatitis or bronchial asthma. Diagnostics includes anamnesis collection, physical medical examination, general clinical and allergological studies (skin scarification tests, identification of specific immunoglobulins). Therapeutic measures provide…
Bird allergy is a type of immunopathological process caused by the body’s hypersensitivity to components of bird feathers, scales, droppings or parasites. Symptoms depend on the reactivity of the body and the ways of penetration of the allergen – lacrimation, swelling of the mucous membranes of the nose, cough, possible development of urticaria, in rare…
Mold allergy is an allergic reaction that develops when mold spores enter the body. The pathological process is more often localized in the respiratory tract, leading to the development of allergic rhinoconjunctivitis and bronchial asthma, allergic bronchopulmonary aspergillosis and exogenous allergic alveolitis. Less common is a lesion of the skin with a picture of atopic…
Penicillin allergy is a reaction of the immune system to the repeated introduction of penicillin antibiotics into the body – benzylpenicillin, ampicillin, oxacillin, amoxicillin. At the same time, the skin is affected (urticaria and Quincke’s edema), the respiratory tract (difficulty breathing, suffocation), anaphylactic shock may develop. Diagnosis of penicillin allergy is based on a thorough…
Metal allergy is a relatively common type of intolerance caused by the ingestion of metal element ions into the human body and their binding to proteins. Symptoms depend on the type of interaction with the provoking substance, dermatitis is most often registered in the form of redness, itching, burning. Diagnosis is made on the basis…
Latex allergy is a set of pathological conditions that combine intolerance to products made of natural or (less often) synthetic rubber with the development of local or systemic reactions. Symptoms of pathology range from signs of dermatitis (redness, itching, burning) to lacrimation, nasal congestion, difficulty breathing, angioedema. Diagnostics includes the study of the patient’s anamnesis…
Makeup allergies is hypersensitivity to substances that are part of cosmetics (creams, lacquers, shampoos, lipsticks, perfumes, deodorants, paints, etc.). It is characterized by the development of allergic reactions with damage to the skin, lips, hair and nails. Makeup allergies is more often manifested in the form of urticaria and contact dermatitis, the upper respiratory tract…
Insulin allergy is an increased sensitivity of the immune system to insulin and protein impurities present in the drug, manifested by the development of a local or systemic allergic reaction when a minimum amount of bovine, porcine or human insulin is administered. More often there are local reactions with the appearance of edema, itching, soreness…
Pet allergies is one of the most common allergic conditions caused by intolerance to antigens of wool, feathers, skin particles or pet waste products. The symptoms depend on the ways the allergen enters the body – itching, lacrimation, nasal congestion, sneezing, sore throat are most often registered. The pathology is determined by studying the patient’s life…
Peanut allergy is a common variant of food allergy, which is caused by 18 specific groundnut proteins. The probability of food intolerance increases with genetic predisposition, the use of cosmetics with peanut oils, late introduction of the product into the diet. Allergic reactions are manifested by skin rashes, gastrointestinal and respiratory symptoms, in severe cases…
