Asthma in children aged 1–5 years is characterised by recurrent transient episodes of wheeze triggered by viral colds. This is labelled “preschool viral wheeze” and is commonly treated with inhaled bronchodilators and oral corticosteroids. Persistent wheeze is associated with increased systemic eosinophil priming which is thought to be a risk factor for the development of atopic asthma.

In this randomised placebo controlled trial, children aged 1–5 years with known viral wheeze were stratified into either high or low eosinophil priming groups and parents administered 20 mg prednisolone or placebo for 5 days at the start of the next episode of viral wheeze. The primary outcomes were 7 day mean daytime and night time respiratory symptom scores.

217 children were randomised and outcome data were available for 51 and 69 children who received prednisolone or placebo, respectively. There was no improvement in daytime and night time symptom scores and no reduction in salbutamol use and hospital admissions in children treated with prednisolone compared with placebo. There were no differences between high or low eosinophil priming groups.

This study suggests no clear benefit of parent initiated oral prednisolone for preschool viral wheeze.