Definition

Stuffy or runny nose, sneezing, itching in the palate, eyes red and stinging. This is not necessarily a “common cold” but may be of allergic rhinitis.

Allergic rhinitis is characterized by inflammation of the nasal mucosa.

It is manifested by a set of symptoms (sneezing, nasal discharge and obstruction) due to an excessive immunological reaction in the presence of a foreign substance is called an allergen. Allergens are natural components of the environment such as pollen or cat hair, but the immune system of a person sensitive (or allergic) responds inappropriately.

Allergic rhinitis may be associated with asthma, allergic conjunctivitis and other diseases such as sinusitis or otitis.

Traditionally, allergic rhinitis were distinguished into two entities:

* Seasonal allergic rhinitis or “hay fever” or pollinosis, easily identifiable as occurring each year in the same season and most often associated with conjunctivitis. Seizures occur when the arrival of pollen, when their concentration in the air increases.
* Allergic rhinitis “perennial” that lasts all year and is often associated with asthma. The allergens are usually mites (house dust), animal dander (especially cats), mold and cockroaches.

Classification of rhinitis

Allergic rhinitis is classified according to frequency of symptoms and their severity and impact on quality of life of patients:

* The time factor
Rhinitis is considered intermittent when symptoms are present less than four days per week or less than four weeks per year. She was diagnosed as persistent when symptoms are present, rather more than four days per week over four consecutive weeks per year.
* The severity factors
Rhinitis is slight if the patient does not feel any of the following symptoms: sleep disturbance, impact on daily activities, sports, business or school, disabling symptoms.
Conversely, rhinitis is moderate to severe when the patient suffers from at least one of the problems cited above.

Mechanism of allergic reaction

Allergic rhinitis is characterized by an abnormal reaction of the nasal mucosa to an allergen. These allergens generate inflammation responsible for clinical symptoms of rhinitis. It is an allergic reaction.

The mechanism of the allergic reaction is a complex phenomenon that consists of 2 phases:

* 1. Awareness
This phase called awareness begins when the individual enters for the first time in contact with the allergen. The allergen is then considered by the immune system as a hazardous substance. He is captured by a macrophage (cell host defense); The latter communicates with cells that will secrete antibodies (IgE) specific to the allergen. These IgE antibodies attach themselves to mast cells and are subsequently able to recognize the allergen.
* 2. Phase 2: The reaction in allergic rhinitis
When the allergen enters the body again, it is recognized by IgE present on mast cells while in the nasal mucosa. The IgE will then defend the body against the allergen and trigger a chain reaction – which results in clinical manifestations of allergy: runny nose, itching eyes, etc.