The diagnosis of asthma in infants and preschool
children relies on clinical judgement based on a combination of
symptoms and physical findings, family history, the presence of
other clinical atopic disease (eczema and allergic rhinitis) and
response to bronchodilators.
Wheezing in infants up to 12 months old is most
commonly transient and due to either acute viral bronchiolitis
or to the presence of relatively small and/or floppy airways,
which produces noisy breathing but no associated morbidity.
Neither of these forms of infant wheeze respond to anti-asthma
therapy.
When cough is the predominant symptom of suspected
asthma in a young child, careful assessment is needed to avoid
making an incorrect diagnosis of asthma, or instigating
inappropriate treatment. The absence of wheeze and/or shortness
of breath makes asthma unlikely. Cough alone (recurrent
non-specific cough) is most likely due to recurrent viral
bronchitis, which is unresponsive to both bronchodilators and
preventive therapy including inhaled corticosteroids (ICS).
Recurrent non-specific cough usually resolves by age 6 or 7
years and leaves no residual pulmonary pathology.
Asthma management in children should be based on a
careful assessment of the clinical pattern. Childhood asthma is
classified as infrequent intermittent, frequent intermittent,
mild persistent, moderate persistent or severe persistent
(Figure 1). This classification is based mainly on clinical
information, but spirometry and peak expiratory flow variability
can provide useful additional information in children older than
7 years. The initial assessment should be reviewed regularly.
For guidelines on assessment and classification of asthma
pattern and severity in children, see Asthma Management
Handbook 2006.1
Intermittent asthma accounts for up to 95% of
childhood asthma.2 Because episodes are usually
triggered by a viral upper respiratory tract infection, the
terms “intermittent asthma” and “virus-associated wheeze” or
“viral-induced wheeze” are sometimes used synonymously in
clinical literature.3
Figure 1. Asthma patterns
in children
Typical patterns of deterioration in symptoms or
fall in lung function parameters over time, relative to good
asthma control (horizontal lines).
Montelukast is currently recommended as a
treatment option for children with frequent intermittent asthma
or mild persistent asthma.
