How to Diagnose Bronchial Asthma in Children?

Bronchial asthma is a relatively common disease among children. It occurs due to a chronic (long-term) inflammation of the airways characterised by recurring and variable symptoms, bronchospasm, and reversible airway obstruction. Common features of bronchial asthma include cough, wheezing, difficulty breathing (shortness of breath), and chest tightness.

Diagnosis of bronchial asthma in children mainly depends on the features of clinical history and examination. It depends on identifying a characteristic pattern of episodic symptoms in the absence of an alternative explanation. Some clinical features increase the probability of bronchial asthma while some lower the possibility.

Features, which raise the probability of bronchial asthma

If your child has more than one of the following symptoms, the probability of asthma is high. Especially, if these symptoms are recurrent; are more intense at night as well as in the early morning; appear in response to, or worse following, physical exertion or other triggering factors, like exposure to cold or damp environment; pets, or with laughter or emotions; or arise apart from colds.

Symptoms are:

Cough
Wheezing
Chest tightness
Shortness of breath (difficulty breathing)

Wide-spread wheezing sound heard on auscultation by a health-care professional.

Clinical history of atopic disease

Family history of bronchial asthma and/or atopic disease

History of improvement in lung function or clinical features in response to sufficient treatment.

Features, which lower the probability of bronchial asthma.

Isolated coughing in the absence of shortness of breath or wheezing

Symptoms, which appear with colds only, without interval symptoms.

History of productive cough

Prominent light-headedness, dizziness, or tingling hands or feet

Repeatedly normal chest examination, when the child is symptomatic.

Symptoms directing to alternative clinical diagnosis

No improvement following a trial of asthma treatment

Normal spirometry or peak expiratory flow (PEF), when the child is symptomatic.

Following a detailed clinical history and examination, a child can normally be categorised into three groups:

Group with a high probability – diagnosis of bronchial asthma probably
Group with an intermediate probability – diagnosis of bronchial asthma doubtful
Group with a low-probability – diagnosis rather than bronchial asthma likely

Children with a high probability of bronchial asthma

Children with a high possibility of bronchial asthma should be offered a trial of asthma treatment. Following the treatment, a health-care professional should review and assess the response. Children with a poor response need further testing.

Children with an intermediate probability of bronchial asthma

For children with an intermediate possibility of bronchial asthma, who can do spirometry and have clinical evidence of airflow obstruction, the health-care professionals should assess the change in lung function (PEF or FEV1) in response to an inhaled bronchodilator medication (reversibility of airway obstruction) and/or the response to a trial of therapy for a specific period.

If the trial of treatment is effective, or if there are significant features of reversibility, a diagnosis of bronchial asthma is possible. The child should be offered continuous asthma treatment with the minimum effective dose of therapy. The health-care professional will consider a trial of reduction, or withdrawal of asthma medication later.

If there is no considerable reversibility of symptoms and signs, and the trial of asthma treatment is not effective, the health-care professional will consider further testing for alternative diseases.

Children with an intermediate possibility of bronchial asthma, who cannot do spirometry, should be provided a trial of asthma treatment for a specific period. If therapy is effective, they should be offered asthma medication and reviewed. If treatment is not effective, the health-care professional will stop asthma therapy, and consider further testing for alternative medical conditions as well as specialist referral.

Children with an intermediate probability of bronchial asthma, who can do spirometry and have no features of airflow obstruction, should be provided further testing for bronchodilator reversibility, atopic status, and if possible, airway (bronchial) hypersensitivity using mannitol, methacholine, or exercise. They should be offered specialist referral too. This usually applies to children between five and twelve years.

Children with a low possibility of bronchial asthma

These children should be provided further detailed investigation and specialist referral.

If there is inadequate evidence for a strong diagnosis of bronchial asthma but no clinical features to suggest an alternative diagnosis in children, especially under five years, there are some possible assessment options, depending on severity and frequency of symptoms. They include: