Atopic dermatitis: Correlation of severity with allergic sensitization and eosinophilia

Background: It is widely acknowledged that food sensitization is related to atopic dermatitis in infants and young children. Objective: To investigate the association of aeroallergen sensitization with increased rates and severity of atopic dermatitis in school children. Methods: We enrolled 576 children (mean age, 9.4 ± 1.8 years) from six elementary schools. Atopic dermatitis was diagnosed by questionnaires, and severity was rated by physical examinations graded by using the Scoring Atopic Dermatitis (SCORAD) index. Skin-prick tests to 22 common allergens (6 aeroallergens and 16 food allergens) were conducted. Logistic and linear regression analyses were performed by using two models: model I adjusted for age, sex, and body mass index z score; and model II adjusted for all model I factors plus asthma and allergic rhinitis. Results: We diagnosed atopic dermatitis in 22.4% (n = 129) of the children, sensitization to foods in 48.3% (n = 278), and sensitization to aeroallergens in 11.3% (n = 65). A total of 26.2% of the children (n = 149) had mild and 6.5% had moderate-to-severe symptoms and signs of atopic dermatitis (n = 37). Atopic dermatitis was associated with sensitization to aeroallergens and eosinophilia (model I), but this risk was no longer significant after additional adjustment for current allergic status (model II). However, the relationship of the total SCORAD score with aeroallergen sensitization and eosinophilia was significant in model I and model II. Conclusion: The severity of atopic dermatitis correlated with the extent of allergic sensitization and eosinophilia. Analysis of our results suggests that more sensitization to dust mites and eosinophilia are related to increased rates and high severity scores of atopic dermatitis.