Prevention and treatment of recurrent viral-induced wheezing in the preschool child.

OBJECTIVE: To summarize the recent evidence in the treatment of viral-induced wheezing in the infant and preschool aged child. DATA SOURCES: Published literature obtained through PubMed database searches. STUDY SELECTIONS: Studies relevant to phenotypes and treatment of wheezing illnesses in infants and preschool children were included. RESULTS: Recurrent wheezing in preschool children is common and is frequently triggered by viral respiratory tract infections. Certain phenotypes may respond to treatments differently, depending on the risk factors identified. Inhaled corticosteroids, administered continuously or intermittently, reduce the risk of virus-induced wheezing episodes. The use of leukotriene modifying agents may have a role in wheezing episodes in a select group of preschool children. Early administration of azithromycin reduces the risk of severe lower respiratory tract illnesses in children. The effect of oral corticosteroids on wheezing episodes in young children varies by degree of episode severity. CONCLUSION: Recurrent viral-induced wheezing illnesses has been the focus of many clinical trials, which now provide an increasingly robust evidence base for management. Additional research is needed to define optimal strategies, to best match therapies to specific phenotypes and endotypes, and will eventually begin to include therapies directed specifically at the viral triggers.