Phenotype-directed treatment of pre-school-aged children with recurrent wheeze.

Wheeze in childhood may comprise different underlying diseases. Disease-specific treatment could potentially improve treatment efficacy. Various attempts have been made to differentiate between pre-school wheeze phenotypes. In this review, the results of clinical trials evaluating treatment of pre-school wheeze are discussed, with specific emphasis on the characteristics and phenotype of the study populations. Evidence suggests that systemic corticosteroids are not beneficial for the treatment of mild-to-moderate exacerbations of pre-school wheeze, irrespective of phenotype. The use of high-dose intermittent inhaled corticosteroid treatment cannot be recommended because of unacceptable side effects. Treatment with regular inhaled corticosteroids and leukotriene antagonists offer modest benefit, but neither treatment reduces hospitalisation rates. There is currently some evidence for a phenotype-specific effect of treatment. Phenotype-directed treatment of pre-school wheeze is currently limited by our ability to accurately differentiate between clinically useful phenotypes.