Early skin sensitization to aeroallergens.

BACKGROUND: Early detection of aeroallergen sensitization is important as a prognosis factor but may be more difficult in young children. OBJECTIVE: We sought to demonstrate that skin sensitization to aeroallergens was present in a selected group of 0-2-year-old children and that it was associated with environmental exposure and a family history of allergic disease. METHODS: Data on exposure and history were extracted from the files of 824 children seen in the asthma clinic and who were skin tested to a panel of aero- and food allergens. RESULTS: Forty percent of our children demonstrated atopy, 28% were sensitized to aeroallergens, the majority of which to house dust mite. Higher sensitization rates were found in children with large weals to histamine (P<0.001) and in those who slept with soft toys [odds ratio (OR) 1.45, 95% confidence interval (CI) 1.02-2.08]. With a definition of sensitization including the size of the weal to histamine, there was a negative association with a personal history of eczema only (OR 0.66, 95% CI 0.45-0.99). There was no gender-dependent effect and no association with day-care attendance. CONCLUSION: This is one of the largest studies to evaluate skin testing in a selected population of young children. We found a high prevalence of sensitization to aeroallergens, which was associated with exposure to soft toys. Further follow-up of this population will allow assessment of the predictive value of this sensitization.