Atopic dermatitis in early infancy predicts allergic airway disease at 5 years.

Background: Screening tests for atopy risk in newborns have a low predictive value. If early atopic symptoms and signs could be used as predictors for the next expected atopic disorder then secondary prevention could be employed. The aim of this study was to evaluate the capacity of early atopic dermatitis to predict aeroallergen sensitization and the manifestation of respiratory atopic disorders at 5 years of age.

Methods: 1314 children of a German prospective birth cohort study MAS-90 were followed from birth up to 5 years of age. Atopic dermatitis, asthma and rhinoconjunctivitis were diagnosed from symptoms and signs at physical examinations and by interviews of the parents. Blood was drawn at 1, 2, 3, and 5 years of age. Aeroallergen sensitization was diagnosed by a specific IgE value of at least 0.35 kU/L (CAP class > or = 1) against any of five respiratory allergens (mite, cat, dog, birch, grass).

Results: Atopic dermatitis in the first 3 months was a risk factor for aeroallergen sensitization at 5 years. The risk increased with a positive family history for atopic diseases. Seventy-seven per cent of children with two atopic parents and early atopic dermatitis were sensitized against aeroallergens at 5 years, i.e. could have been predicted in early infancy without any laboratory tests. Although these risk factors were also significantly associated with the manifestation of allergic airway disease, the positive predictive value for this outcome at age 5 years was not yet as high, i.e. 50%.

Conclusion: Infants with very early signs of atopic dermatitis and a positive family history are candidates for early intervention measures against respiratory allergies.