Prediction and detection of allergy development: influence of genetic and environmental factors.

The prevalence of atopic diseases is increasing in northwestern Europe and probably also in the rest of the Western world. Detecting cord blood IgE, in combination with obtaining a family history of atopic disease, seems to be the most valuable method of predicting all forms of atopic disease; however, this will identify only a small proportion of children with subsequent development of atopic disease. Determination of cord blood IgE cannot, without modifications, be recommended as a single test for identifying infants for allergy prevention programs. Skin prick reaction to egg white during the first year of life seems to identify a majority of children in whom allergic disease is going to develop during infancy. Other methods, such as genetic markers of an atopic constitution, eventually may facilitate early identification of infants at risk of atopic disease.