Allergies

This is a common clinical synonym for hyperergic reactions, increased reactivity of the body, and sensitivity to repeated entry of certain substances, usually characterized by antigenic properties, into the body. Allergy can be caused by the effect of altered components of the body itself. It is closely related to immunology. Immunologists often classify allergic diseases under immunology. Under normal conditions, repeated infection does not cause any clinical symptoms, and the pathogen is destroyed. Once immunity is established, protective reactions predominate without cell function and structure damage. The most important aspect of preventing allergic diseases is to identify the allergen. Allergens are antigenic or haptenic substances that sensitize the body and cause allergic reactions. Exogenous allergens are divided into infectious (bacterial, viral, fungal) and non-infectious (food allergens, household, epidermal, pollen, chemical, drug). The majority of non-infectious allergens are of plant origin. This includes plant pollen, which causes allergic disease called pollinosis. A person can be sensitive not only to pollen but also to other parts of plants. For example, an allergic skin reaction can be caused by poison ivy leaves, etc. In Lithuania, trees such as hazel, alder, birch, poplar, maple, oak, and others start to bloom in March and April. This is the period of tree pollen. Grasses bloom abundantly in May and June. Pollen concentration is highest in the morning under calm weather conditions. Human hair, feathers, and epidermal particles are the most common animal-derived allergens. Allergy to medications has become important in recent years. Allergy is becoming an increasingly significant problem as more people suffer from allergic diseases. People consume more medications, vaccination is spreading, various chemical and synthetic substances are increasing in our homes, industries, agriculture. Often all these substances have allergenic properties, hence allergy is called a civilization disease. The abundance of allergens, various ways of their entry into the body, the influence of other factors lead to the polymorphism of allergic disease symptoms and complications. This complicates the symptomatology of allergies. The European Academy of Allergology and Clinical Immunology recommended the nomenclature of allergic diseases. According to it, allergic diseases are classified as follows: 1) allergy; 2) anaphylaxis; 3) increased sensitivity to food products; 4) increased sensitivity to drugs; 5) rhinitis; 6) asthma; 7) urticaria; 8) conjunctivitis; 9) atopic eczema or dermatitis.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė