Wheeze is extremely common in pre-school children, with an estimated 25% of children having an episode of wheeze before 18 months. Viral-induced wheeze is now one of the most common diagnoses made on paediatric wards. There is however ongoing debate regarding the classification of wheeze in this age group and the most appropriate management.

Over recent years, led by the European Respiratory Society Task Force, the favoured classification for pre-school wheeze is to divide children into one of two groups;

• episodic viral wheeze: only wheezes when has a viral upper respiratory tract infection (URTI) and is symptom free inbetween episodes
• multiple trigger wheeze: as well as viral URTIs, other factors appear to trigger the wheeze such as exercise, allergens and cigarette smoke

Episodic viral wheeze is not associated with an increased risk of asthma in later life although a proportion of children with multiple trigger wheeze will develop asthma.

Management

Parents who are smokers should be strongly encouraged to stop.

Episodic viral wheeze

• treatment is symptomatic only
• first-line is treatment with short acting beta 2 agonists (e.g. salbutamol) or anticholinergic via a spacer
• next step is intermittent leukotriene receptor antagonist (montelukast), intermittent inhaled corticosteroids, or both
• there is now thought to be little role for oral prednisolone in children who do not require hospital treatment

Multiple trigger wheeze

• trial of either inhaled corticosteroids or a leukotriene receptor antagonist (montelukast), typically for 4-8 weeks