Allergy

Allergy is a disorder of the immune system in which the defenses respond inappropriately and they identify external substances as harmful that, due to their nature, are inoffensive. The most frequent allergy is respiratory - rhinoconjunctivitis and allergic asthma- which affects around 25% of the general population.
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Allergy explained in first person

Professionals and patients explain how you live with the disease
There are many factors, many causes that may explain why there are increasingly more and more allergic diseases, such as environmental contamination, the type of diet, stress factors that act on the immune system, the microbiome itself, these multiple microorganisms that live in our body.

Allergy is a disorder of the immune system in which the defenses respond inappropriately and they identify external substances as harmful that, due to their nature, are inoffensive.  

The person with an allergy develops defenses (immunoglobulins) to certain substances, called allergens, to which they are exposed. The allergens can be substances or particles that they inhale (mites, pollens, animal skin flakes, etc.), foods, drugs, insect venom, contact elements (metals, perfumes, cosmetics, gums, etc.).

The clinical characteristics of the allergic disease differ as regards the type of hypersensitivity mechanism involved in the allergic response:

Immune system cell with antibodies

Immediate hypersensitivity or IgE mediated. When specific IgE immunoglobulins are involved in the immune response. They are usually reactions that appear quickly after contact with the allergen (less than an hour).

Lymphocyte

Delayed-type hypersensitivity. When the defences involved are the lymphocytes or white cells.

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Substantiated information by:

Joan Bartra Tomàs
Rosa Maria Muñoz Cano

Published: 24 July 2019
Updated: 24 July 2019

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