Phenotypes of Recurrent Wheezing in Young Children

Abstract

Nearly 25% of preschool children have recurrent wheezing. Early identification of those who are at higher risk for exacerbations and respiratory infections is key. To investigate early-onset wheezing in children aged 24-72 months, a review from a 7-year period in an asthma specialist clinic was performed. Criteria included presence of recurrent wheezing with a recent history of >2 systemic steroids (OCS) bursts per year and/or ≥3 courses of antibiotics (ABX) per 6 months. Both OCS and ABX treatments were for wheezing exacerbations prescribed by their PCP/ER staff. Patient characteristics and labs were collected, and questionnaires were sent to families to document subsequent use of OCS or ABX. Of 101 children (mean 51 months, 59% male) studied, 43% had >2 OCS/yr, and 57% had ≥3 ABX/6months. At baseline, mean serum eosinophils was 233/uL, total IgE was 102 kU/L, and only 2 normal antibody titers to S. pneumoniae were present. Post-vaccination pneumococcal titers were responsive with 14 titers normalized. Other characteristics were presence of positive allergen sensitization 45%, eczema 39%, parental asthma 28%, and household pets 47%. Of 72 returned questionnaires, 82% responded with less bursts/use of OCS and ABX for wheezing exacerbations post-vaccination. Vaccine responder’s baseline eosinophils was 215/uL, while non-responders were significantly higher at 370/uL. There was no significance in any other baseline values. Identification and vaccination for low pneumococcal titers in those with non-elevated eosinophil counts can reduce wheezing exacerbations. Higher eosinophil counts in young wheezers can identify those at higher risk for increased OCS and ABX use.