Current strategies for phenotyping and managing asthma in preschool children

Half of all children will experience an episode of wheezing by 6 years. Recurrent preschool wheezing is associated with early lung function loss and has a lifelong impact on airway health, so deciding which children should be treated to prevent exacerbations while also avoiding irreversible health consequences is crucial. The purpose of this review is to provide a practical approach to the pediatric patient under 5 years of age with asthma, with particular attention to the recent enhanced identification of wheeze phenotypes.

Here, we note the difficulty of defining 'asthma' for this age group and advocate that it be determined by the set of respiratory symptoms presented, without assumptions about the underlying mechanisms of the disease. In addition, we propose a forward-looking approach, what treatment to apply to particular phenotypes, which child should be treated, and, if so, which treatment strategy to choose. No clear recommendation exists for the management of nonallergic preschool wheezing, a substantial clinical and research gap.

We recommend an empathetic approach to parent anxiety and considering objective markers: timing, severity, and frequency of symptoms, along with an assessment of other biomarkers, including viral etiology, aeroallergen sensitization, and blood eosinophils, that contribute to successful decision-making.