Allergic sensitization profile in 0-5 year old children with wheezing and/or atopic dermatitis

Background: Although allergic diseases are frequent in childhood, few studies have characterised the IgE sensitization profile among young children with allergic-like symptoms. Objective: To determine the prevalence and the type of allergic sensitization, as well as the demographic and environmental factors related to both characteristics, among 0-5 year old children presenting with wheezing and/or atopic dermatitis. Methods: Collaborative cross-over study developed in the paediatric setting of 20 Spanish Primary Health Care Centres. An allergology evaluation including blood determination of specific IgE antibodies to common inhalant and food allergens was performed on 468 children who presented with wheezing and/or atopic dermatitis. Results: Allergic sensitization was detected in 32.4% of the children with wheezing (95% confidence interval, 95%CI, 26.3-38.6%), in 54.8% of the children who had atopic dermatitis (95%CI, 42.1-67.6%) and in 39.2% of the children with both processes (95%CI, 32.0-46.4%). The risk of allergic sensitization was sex related (mate versus female adjusted odds ratio, ORA, 1.91, 95%CI, 1.24-2.95), and also related to the age (3-5 versus 0-2 year old ORA 1.96, 95%CI, 1.27-3.0), type of early feeding (maternal milk versus infant formula ORA 0.51, 95%CI, 0.31-0.84) and geoclimatic area (ORA Continental versus Atlantic 2.26, 95%CI, 1.30-3.93). Compared to the Atlantic area, the Continental area the sensitization was lower to mites (ORA 0.16, 95%CI, 0.07-0.36) and higher to grass (ORA 4.65, 95%CI 1.99-10.86), cow milk (ORA 5.17, 95%CI, 1.71-15.62) and egg (ORA 5.26, 95%CI, 2.04-13.62), whereas in the Mediterranean area the sensitization was lower to mites (ORA 0.29, 95%CI, 0.13-0.64) and higher to cow milk (ORA 3.81, 95%CI, 1.20-12.14) and egg (ORA 5.24, 95%CI, 1.94-14.20). Conclusion: A significant proportion of small children treated at the paediatric primary health care centres due to wheezing and/or atopic dermatitis had allergic sensitization. There appears to be a geoclimatic variation in the prevalence of sensitization to inhalant and food allergens among young children with allergic like symptoms who live in Spain. (C) 2009 Asociacion Espanola de Pediatria. Published by Elsevier Espana, S.L. All rights reserved.