What is Respiratory Allergy ?

Respiratory Allergy Definition

Respiratory allergy is defined as an inappropriate or excessive reaction of the body's immune system following contact with a foreign substance called an allergen.
In the context of a respiratory allergy, the allergen will be inhaled by the individual, we speak then of pneumallergene: pollens for example.  Respiratory allergy can take two forms: allergic rhinitis and allergic asthma.

Epidemiology

Between 15 and 20% of  population is currently affected by respiratory allergies. asthma affects 10% of children and 6 to 7% of adults while allergic rhinitis related to pollen affects 15% of the population aged 15 to 50 years.

Prevention Respiratory Allergy

Respiratory allergies affecting people with a genetic predisposition ,called atopic terrain, there is no way of prevention per se.
However, their development is aggravated by smoking both active and passive  and pollution or viral superinfections.
It will therefore be necessary to take care not to smoke and not to expose oneself to the smoke of cigarettes of the relatives.
It is also advisable to stay home as much as possible and not to practice physical activity during pollution peaks.

Causes Respiratory Allergy

Allergy occurs in individuals with atopic terrain, that is, genetic predisposition. For example, children with atopic parents will have 40 to 60% risk of being atopic compared to only 5 to 10% if their parents were not atopic.
Respiratory allergy (asthma or rhinitis) is due to the inhalation of airborne or pneumallergenic allergens.

The most commonly encountered pneumallergens are:

acarians,
pollen,
The molds,
Animal dander: feathers, scales, hair (cat, dog, horse ...)

Mechanisms causing the disease

The mechanism of respiratory allergy consists of two phases:

an awareness phase
For the first time, the individual is in contact with the foreign substance called allergen. This phase is silent and the individual has no symptoms. His body will then make antibodies in response to the allergen (an antibody is a biological molecule that will recognize and neutralize the antigen: microbe, allergen, ...). The antibodies will bind to one type of cell, the mast cells and wait for the next contact with the allergen.

an allergic reaction phase
In a second contact with the allergen, the already sensitized individual (that is, the manufacturer of antibodies against the allergen) will present the symptoms of the allergy. Indeed, the antibodies will bind to allergens and trigger the activation of mast cells and the release of chemicals (such as histamine or leukotrienes ...) at the origin of the allergic reaction.

Symptoms Respiratory allergies / manifestations

The symptoms of allergic rhinitis are defined by the following clinical signs, which can be quantified by a score called P.A.R.E.O score:

P for pruritus: itching of the nose and / or palate,
A for anosmia which is a loss of smell,
R for rhinorrhea: the nose runs,
E for sneezing,
O for nasal obstruction, that is, a stuffy nose.
It is also possible to suffer from sinusitis or allergic conjunctivitis.

Allergic asthma is manifested by:

difficulty breathing,
wheezing,
a feeling of tightness in the chest,
a cough of irritation,
shortness of breath after exercise

Symptoms may appear after several years of exposure to an allergen when there were no outbreaks initially.