Abstract
Preschool wheezing is extremely common. Despite its prevalence, prognosis is often hard to determine. Preschool wheezing is not without significant associated morbidity which may result in increased utilization of medical resources. The child with preschool wheezing may represent one of at least three distinct phenotypes, each having different clinical significance and therapeutic implications. The challenge to the clinician is to correctly identify the operative phenotype as a basis for family education, effective therapy and ultimately a reasonable assertion regarding prognosis. The current article reviews clinical presentation, potential etiologies and triggers as well as historical, hereditary and laboratory markers that may aid in the diagnosis and management of this challenging presentation among preschool children.