Asthma: from symptoms to diagnosis

This chronic respiratory disease is due to a permanent inflammation of the bronchi. What are the symptoms of asthma? How is the disease diagnosed? Doctissimo answers all your questions. 

Asthma: general symptoms

In a person with asthma, the inflammation of the bronchi and the contraction of the muscles lead to a reduction in the diameter of the bronchi. The air passes more with difficulty. 

Asthma  usually manifests itself in different forms:

• Cough , usually dry and occurring in fits. It can announce the beginning of a crisis or be its main manifestation;
• Ringing in the chest is certainly the most common symptom of asthma;
• The respiratory discomfort associated with wheezing can also take different forms. Oppression (or feeling of blocked chest) can be taken for a cardiac alert in seniors.

These signs can occur at night or during exercise, often interspersed with long periods of calm. But all too often, these signs go unnoticed and the diagnosis only comes late . " I happen to meet patients who have had such symptoms for months or even years before being diagnosed with asthma. Only one of these symptoms can suggest the disease. They are clues in the same way as the presence of asthma. "family history of asthma or allergy " says Dr. Pierrick Hordé, allergist.

Symptoms of an asthma attack

The best-known symptom of asthma is the attack , which causes difficulty in inhaling and especially exhaling air from the lungs . These "bronchospasms" can be triggered by different factors such as effort, humidity, dust, cigarette smoke, pollens, etc. One easily distinguishes a whistle during expiration, attesting to the narrowing of the bronchi. The air is then trapped in the chest, the thorax blocked. By coughing, the body seeks to reject the phlegm that accumulates in the bronchi.

The crisis can be explained by three phenomena:

• The bronchial muscle contracts (bronchoconstriction);
• The wall of the bronchus thickens (oedema);
• The internal wall secretes important mucus (hypersecretion).

The diagnosis of asthma

Faced with suggestive respiratory symptoms, the doctor should look for:

• Family history of allergy, asthma, eczema...
• The existence and duration of breastfeeding ;
• Digestive disorders during weaning and the introduction of cow's milk;
• Repeated ENT infectious episodes leading to antibiotic prescriptions, paracentesis and removal of the adenoids;
• Repetition of respiratory episodes in a stereotyped pattern;
• The occurrence of seizures during exposure to allergens;
• Improvement of symptoms by active drugs: corticosteroids, beta-stimulants;
• The ineffectiveness of antibiotics and antitussives;
• Signs suggestive of allergy: fold of the lower eyelid, folliculosis, edematous conjunctivitis, pale nasal mucosa,  redness  of the pharynx, mucous otitis, dry skin, accentuation of the palmar folds, etc.

breath measurement

The diagnosis of asthma is therefore based on the doctor's clinical examination and on respiratory function tests (EFR) which will confirm the presence of the disease. " Lasting approximately 20 minutes, these non-invasive examinations make it possible to assess the extent of the respiratory function deficit, to look for any associated functional abnormalities, to assess the reversibility of the obstruction and to monitor evolution of the disease " explains Dr Hordé.

EFRs consist of the performance of two examinations: spirometry and plethysmography . As part of these measures, the patient is seated in an airtight chamber and breathes exclusively through a mouthpiece.

Spirometry is the measurement of inspiratory and expiratory flows. This is the examination that looks for bronchial obstruction (asthma is an obstructive syndrome). The monitoring of the disease is done by spirometry alone.

Plethysmography consists of measuring inspiratory and expiratory volumes and flows. It has an interest in the child who has an asthmatic equivalent with the presence of a cough as the only symptom for example.