What are the differences between allergies and respiratory infections?
On the one hand, pulmonary infections can be both bacterial and viral infections of the upper airway, composed of the nasal passages, mouth, pharynx and larynx; and the lower airway, composed of the trachea, bronchi and bronchioles. In the former, pathologies such as rhinosinusitis, laryngitis, laryngotracheobronchitis, etc. can occur, and in the latter, bronchitis, pneumonia, among others. Together they constitute a group of pathologies that occur in both children and adults, with a special peak in the autumn-winter period, and which are evaluated in Pneumology consultations.
Rhinitis and allergic asthma are considered to be two manifestations of a single disease, respiratory allergy. In this case the causative factor is not a germ but an immune reaction to an external agent. Respiratory allergies occur when the susceptible person breathes in particles capable of generating an immunological reaction.
What types of respiratory allergies are there?
The most common aeroallergens are found in pollen grains from trees, grasses and plants, household dust, damp fungi and pets. The particles of these aeroallergens are small in size so they are localized in the air and reach the nasal mucosa through inspired air. A very important part of our defenses are the antibodies that bind to these harmful agents and eliminate them protecting us.
However, allergic people produce a special type of antibodies, of the IgE class, in excess. When IgE and the allergen meet, an allergic reaction is triggered. If this happens in the nasal mucosa, rhinitis symptoms occur, which is the most frequent allergic disease but can evolve at bronchial level causing bronchial asthma from allergic to atopic.
What symptoms are caused by respiratory allergies?
When an allergen and IgE antibodies synthesized by the allergy sufferer come into contact, an inflammatory disorder of the mucous membranes lining the inside of the nose, known as allergic rhinitis, occurs. It is distinguished by nasal itching, sneezing, abundant mucus and nasal obstruction.
Allergic rhinitis affects between 10 and 25% of the population and has a strong impact on their quality of life, since it reduces school and work performance and constitutes a significant economic burden.
It is also a risk factor for developing asthma. Other common complications are sinusitis, nasal polyps and conjunctivitis.
On the other hand, allergic bronchial asthma is an inflammatory disease of the bronchi that causes them to become obstructed, thus impairing breathing. The clogging is due to an immunological reaction between the allergen aspirated and the antibodies generated by the allergic person.
Allergic asthma accounts for 70% of all types of asthma and is the most common chronic condition in children and young adults. Inflammation is linked to bronchial occlusion (bronchospasm) and increased mucus secretion. In many cases, the bronchi also react in this way to respiratory infections, cold air or physical exercise (bronchial hyperresponsiveness).
The symptoms of asthma are recurrent coughing spells, shortness of breath (dyspnea), chest tightness and wheezing. Often asthma appears in the form of crises, aggravate and require emergency treatment. Asthma is accompanied by alterations when the functional exploration of the respiratory system (spirometry) is performed, which helps to certify the diagnosis, determine its severity and know the response to treatment.
Allergic asthma is often associated with spasmodic cough and allergic rhinitis, which may precede it in time.
How are these types of allergies treated?
The treatment for respiratory allergy, once it has been correctly diagnosed and the responsible allergens have been determined, is based on three main aspects that can complement each other:
- Preventing exposure to the allergen, which may be sufficient to control the disease, especially in the case of specific allergies to animal epithelia. It is practically impossible to avoid exposure to the vast majority of environmental allergens (mites, pollens and fungi), but some hygienic measures can reduce this exposure.
- Administration of drugs that have an effect on symptoms, such as antihistamines, anti-inflammatory drugs, bronchodilators or inhaled corticosteroids. It should be considered that the positive effect disappears when the medication is stopped. It is important to perform spirometric controls to see the evolution of bronchial asthma.
- Desensitizing immunotherapy is considered the most complete treatment for respiratory allergy and is achieved through allergy vaccines. Specific immunotherapy allows to reach immunological tolerance after a long term treatment and always with control by the specialist.