Asthma in Children
Asthma is one of the most common chronic disease of childhood and a leading cause of childhood morbidity, as measured by school absences, emergency department visits and hospitalizations. It is considered to be a heterogeneous disease - a syndrome - characterized by chronic airway inflammation.
- Wheeze - a whistle on the chest, shortness of breath and cough manifested by activity limitation and nocturnal symptoms or awakenings without other signs of infection, such as fever
- Chest tightness
- Presence of risk factors to develop asthma
- Therapeutic response to controller treatment.
The Symptoms may vary over time and in intensity, together with variable expiratory air flow limitation.
Some popular classifications of asthma in pre-schoolers are showcased below
|Symptom based||Time trend based|
|Episodic wheeze: Wheezing often in association with URTI, without symptoms in between||Transient wheeze: Those who wheezed in the first 3 years of life and did not have any wheeze by the time they were 6 years old|
|Multiple-trigger wheeze: Episodic wheezing and symptoms also occurring between these episodes, e.g. during sleep or with triggers such as crying, laughter or exercise||Persistent wheeze: Those who wheezed in the first 3 years of life and continued wheeze when they were 6 years old|
|Late-onset wheeze: Those who did not wheeze in the first 3 years but has wheezing at 6 years of life|
It is challenging to arrive at a confident diagnosis of asthma in children 5 years and younger as episodic respiratory symptoms such as wheezing and cough are also common without asthma (such as during viral infections of the lower airways).
But the diagnosis of asthma can be made with more certainty if the child has other symptoms of allergy (eczema, food allergy, etc.) or has a positive family history of allergy.
Tests to Assist in Diagnosis
No single test with absolute certainty can diagnose asthma in children 5 years and younger, but the following tests can be used as adjuncts to facilitate the diagnosis.
- Therapeutic trial: A trial of treatment with a regular low dose of inhaled corticosteroids (ICS) for at least 2–3 months and with as-needed short-acting beta2-agonist (SABA) may help in making the diagnosis of asthma.
- Atopic Tests: Skin prick testing or determination of allergen specific immunoglobulin E can be used to assess sensitisation to specific allergens.
- Chest X-ray: A plain chest X-ray is not routinely indicated in the diagnosis of asthma. It may help if the patient presents with signs not typical of asthma or in doubt about the diagnosis.
- Lung function testing: Due to difficulty in performing reproducible values, lung function testing is not routinely used, but some four years old or older can do it with good results.
- Exhaled nitric oxide: Fractional concentration of exhaled nitric oxide (FENO) can be measured in young children during tidal breathing, and normal reference values have been published for children aged 1–5 years
- Assess: Diagnosis, symptom control, risk factors, inhaler technique, adherence, parent preference
- Adjust treatment: Medications, non-pharmacological strategies, and treatment of modifiable risk factors
- Review: Response including medication effectiveness and side-effects.
Assessment of Asthma
Asthma control means the extent to which the manifestations of asthma are controlled, with or without treatment. It has two components
- Symptom control: Symptom control is assessed with regards to the child's asthma status over the previous four weeks
- Future risk: It is important to understand on how asthma can affect these young children in the future. Even though these factors have not been sufficiently studied in children, but can be considered as important in decision making during step down therapy. Listed below are the risk factors for asthma exacerbations within the next few months
- Uncontrolled asthma symptoms
- One or more severe exacerbation in the previous year
- The start of the child's usual 'flare-up' season
- Exposures: tobacco smoke; indoor or outdoor air pollution; indoor allergens (e.g. house dust mite, cockroach, pets, mold), especially in combination with viral infection
- Major psychological or socio-economic problems for the child or family
- Poor adherence with controller medication, or incorrect inhaler technique
Medications for symptom cntrol and Risk Reduction
It is important to individualize each child's management. Though treatment might still be started with a unified approach, individual monitoring the response and change the strategies if needed is desirable. Based on symptom patterns, risk of exacerbations and side-effects, and response to initial treatment, a stepwise treatment approach should been recommended.
Reviewing response and Adjusting treatment
Every child on treatment should, have a detailed history of asthma symptom control and risk factors at each clinic visit. In a large population of children 5 years or younger, symptoms suggestive of asthma remit and hence the need for continued controller treatment should be regularly assessed (e.g. every 3–6 months).
Diagnosing asthma in youngsters might be difficult, mainly because viral infections can present in a similar way. However, once the diagnosis of asthma has been made, treatment should focus on prevention, allowing the child to have a completely normal life style.
Dr Srikanta J T
Paediatric Pulmonology & Sleep Medicine