DETERMINANTS OF TOTAL AND SPECIFIC IGE IN INFANTS WITH ATOPIC-DERMATITIS

ETAC (Early Treatment of the Atopic Child), a multi-centre predominant ly European study to investigate the potential for cetirizine to preve nt the development of asthma in infants with atopic dermatitis has com pleted enrolment: 817 children have been randomised to 18 months' trea tment with either active or placebo and a subsequent 18 months of post -treatment follow-up. Results of the therapeutic effects will not be a vailable for some time, but the study has provided an opportunity to i nvestigate influences on sensitization to allergens in a large cohort of 1-2 years olds with already established atopic dermatitis, resident in different countries and in different environments. The study shows that in infants with atopic dermatitis, raised serum total IgE has si gnificantly different determinants from that a specific allergen sensi tization. In infancy, increased total IgE is more affected by factors increasing risk of intercurrent infection and non-specific airway infl ammation, such as environmental tobacco smoke exposure (p<0.001) and t he use of gas cookers (p=0.02). Specific allergen sensitization as rep resented by detectable IgE antibodies is influenced primarily by aller gen exposure. In Sweden, low level exposure to allergens is associated with reduced specific allergen sensitization rates even though the in fants already have atopic dermatitis.