Clinical approach to the pre-school child referred with wheeze
and cough
The first step is to determine what respiratory noises are being
described by the parents. The word “wheeze” is used by parents in the
UK at least to describe many different sounds, including the true
musical polyphonic noise of diffuse airway narrowing, upper and lower
airway crackling noises, and even stridor. The use of a
video-questionnaire may help determine this [10, 11]. Asking the
parent to record what they hear on their mobile phone may be useful.
Many medical professionals cannot be relied on to diagnose wheeze
[12], and a healthy scepticism is indicated until the noise has been
assessed by a really experienced professional. In the future, hand-held
detectors with the data downloaded to a smartphone given to the family
may be helpful in resolving this conundrum. If in fact the child has a
chronic wet cough, then investigations need to be directed to confirming
or otherwise persistent bacterial bronchitis [13] and bronchiectasis
[14, 15], both themselves umbrella terms [16], and the
underlying cause thereof, which is beyond the scope of this review.
There are five main groups of causes of chronic respiratory symptoms in
preschool children (Table 2) [17]. It is important to appreciate the
extent of respiratory symptomatology in normal children [18].
Isolated dry cough in an otherwise well child rarely betokens a
significant diagnosis. Asthma should not be diagnosed if cough is the
sole symptom, with no breathlessness, chest tightness or wheeze; neglect
of this rule has led to over-diagnosis and over-treatment of “cough
variant asthma”. All normal children cough; intermittent wet cough in
association with viral colds, with complete recovery between colds, is
normal; and a normal preschool child may have more than ten colds/year
with symptoms lasting 2-3 weeks each time [18]. In my practice, this
“Nursery School syndrome” is very common; the child is placed early
into a childcare facility, by often first-time parents. As a result, the
child (and the parents!) gets a succession of viral colds with very few
healthy days in between each cold. These do not respond to inhalers or
antibiotics; reassurance is what is needed. A prolonged but gradually
clearing post-bronchiolitic syndrome of cough and wheeze is also
commonly seen in an otherwise normal child. Red flags are progressive
symptoms with no symptom free intervals, and a chronic wet cough with no
periods of remission.
Although most pre-school children with cough and wheeze are normal or
have pre-school asthma, in a few these symptoms betoken a serious
disease. The differential diagnosis shows geographical differences, for
example compression of the large airways by tuberculous lymph nodes is
common in endemic areas. Clues on history and physical examination are
shown in Table 3. Most pre-school children with wheeze are managed just
on the basis of history and physical examination. If investigations are
performed, they should be focussed and address two questions, “can I
confirm or exclude an underlying diagnosis?” and “what sort of asthma
does this child have?” (This last is addressed later in the review)
There is no place for doing many investigations in the hope that
something will turn up.