Asthma in children under 3 years of age: features of organization

Article originally published on La Revue du Praticien.

The period from birth to 3 years is a turning point, since in more than half of asthmatics the pathology begins in early childhood.

Before age 3, asthma is defined as “any episode of shortness of breath with wheezing that recurs at least 3 times before age 2 years, regardless of age of onset, presence or absence of atopic stigmata, and apparent cause of asthma. This definition may seem too broad since only a proportion of these infants will go on to have exacerbations. Before making a diagnosis, it is necessary to exclude other causes of shortness of breath.

Clinical manifestations

Sibilants are the most common signs. Their repeated observation and/or during sleep and/or in triggering situations (physical activity, laughing, crying, smoking and/or pollution) is highly suggestive of asthma.

Up to 3 years of age, exacerbation usually takes the form of acute viral bronchiolitis. It begins with ordinary rhinitis or nasopharyngitis, which is preceded for 2-3 days by a dry, hacking cough with polypnea, signs of struggle and wheezing. Spontaneous progression to recovery occurs within a few days.

The term “exacerbation”, which is now distinguished from the term “crisis”, refers to acute symptoms lasting more than 24 hours and/or requiring a change in background inhaled treatment and/or oral corticosteroids and/or hospital admission.

Other tables are possible:

Allergy testing is intended for children with persistent or recurrent respiratory symptoms requiring ongoing treatment or associated with extra-respiratory manifestations compatible with an allergic origin. Prick tests are recommended first.

Diagnosis requires frontal chest radiography during inhalation and exhalation. Its normality allows us to exclude a significant part of other pathologies that mimic asthma.

Differential diagnosis

The younger the child, the higher the likelihood of alternative pathology. Elements that raise doubts about the diagnosis of asthma are:

• Impact on growth
• Stridor, chest deformation.
• Cyanosis, digital clubs
• Chronic congestion
• Purulent sputum

• Persistence of symptoms despite proper asthma treatment.

  Localized expiratory retention primarily suggests the presence of an obstruction (foreign body ++), which justifies bronchial endoscopy.

Beating with batons most often indicates chronic respiratory failure.

A clear break in the growth curve indicates a more severe disease (respiratory, digestive, endocrine) simulating or complementing asthma.

When in doubt, if manifestations are frequent and/or severe, it is necessary to expand research in a specialized environment. Figure 1 shows the case of a child who, after 3 years of bronchiolitis, was assigned asthmatic status. The persistence of symptoms despite treatment with inhaled corticosteroids led to a specialist conclusion: studies led to the discovery of a double aortic arch.

Supported

Drugs
Treatment is based on on-demand beta-2 mimetics (box) and inhaled corticosteroids (IC) as background treatment.

Permitted IR: fluticasone (metered-dose aerosols of 50 mcg), budesonide (suspension for nebulizers 0.5 and 1 mg), beclomethasone (solution for nebulizers 0.4 and 0.8 mg). At low and medium doses, tolerability is good.

Long-acting bronchodilators (BDLA) are only approved for sale from 4 years of age. Montelukast, a leukotriene receptor inhibitor (4 mg granules), is approved from 6 months of age in combination with ICS and from 2 years of age for the same indications as in older children.

Therapeutic strategy
In preschool children, it is mainly based on the frequency of interictal symptoms and an assessment of risk factors for exacerbation (at least one severe crisis in the previous year, environmental smoking, environmental pollution, exposure to allergens, poor compliance).

There are 4 levels in the decision-making algorithm:

Once stabilized, we try to gradually reduce the dose of corticosteroids to the minimum effective threshold. For most young children, it can be interrupted during the summer.

Treatment of exacerbations should be anticipated by providing parents with a written plan of action that encourages them to call the physician (or health care system) if there is no response to a beta-2 mimetic after 1 hour or when a seizure is unusual.

Non-pharmacological measures: necessary
Allergic factors play an important role in bronchial inflammation. Several measures are aimed at reducing exposure to dust mites:

• drop in relative humidity;
• choice of synthetic bedding, anti-mite covers;
• removing carpets, curtains and rugs or regularly cleaning with acaricides or textiles containing these products;
• Regular washing of laundry at temperatures > 55°C with vacuum cleaners equipped with special filters.

  Home hygiene includes:

• disinfestation (cockroaches);
• limiting contact with external allergens, in particular pollen;
• avoiding pets to which the child is allergic;
• mold control;

• eliminating smoking from the environment.

  Results of treatment of asthmatic children of preschool age
  

  Less than half of infants who wheeze will remain asthmatic after age 6. Risk factors for persistence include the severity and frequency of initial manifestations, atopy (especially early sensitization) and environmental smoking. IR can effectively control symptoms, but does not change the natural course of the disease.