Development of Respiratory Allergies, Asthma and Allergic Rhinits in Children with Atopic Dermatitis.

Children with atopic dermatitis (AD) usually develop symptoms when they reach the age of 6-7 years, but the risk of developing respiratory allergies, asthma and allergic rhinitis (AR) remains high. In most children with AD, the development of asthma and AR is associated with sensitization to food allergens and/or aeroallergens, while only a small percentage missed atopic diathesis. In about 35% of children with AD, food allergy is the provoking cause, and 60% of infants who had AD in the first 3 months of life were sensitized against aeroallergens by the age of 5. The aim of the study was to follow development of asthma and AR and to assess the most significant risk factors for developing respiratory allergy. A total of 114 children with AD were followed up for five years. At annual visits, the severity of disease, total immunoglobulin E (IgE) antibody values, skin prick tests, specific IgE antibodies to food allergens and aeroallergens, and absolute eosinophil count were assessed. Information on the family history of atopy and AD, feeding patterns during infancy, data on sensitivity to food allergens and/or aeroallergens, and on the occurrence of bronchial obstruction and nose symptoms were obtained. Asthma developed in 36 children, median age 7.7 years; 33 children had symptoms of AR, and 13 children with AD had both diseases associated; 38 children had sensitivity to food, of which 24 developed asthma and 13 AR; asthma developed in 18/23 children with sensitivity to aeroallergens, and almost an equal number of children developed AR. The increased absolute eosinophil count and specific IgE to aeroallergens and food allergens were the best asthma predictors, while AR predictors were family history and early onset of AD. In conclusion, children with AD are at a significant risk of developing respiratory allergies, and those with the increased absolute eosinophil count, positive specific IgE to aeroallergens and food allergens, heredity of AD, and early onset of AD are at the highest risk. Identification of risk factors will enable us to improve the treatments of AD in order to reduce the severity of disease and prevent manifestation of respiratory allergy.