Does a positive IG-E test mean an elimination diet in atopic dermatitis?

A study of 125 children (median age, 4 years) who had been placed on elimination diets primarily because of a positive serum immunoglobulin E (IgE) immunoassay result suggests that the answer to this question is no.

Investigators performed retrospective chart reviews of children who had been referred to a health center for evaluation of atopic dermatitis (AD) and food allergy. Specific IgE tests performed before referral varied and included traditional skin prick tests, fresh food skin prick tests, food-specific immunoassays, and total serum IgE level.

Investigators performed a complete history and physical examination, reviewed previous laboratory data, and performed oral food challenges (OFCs) for foods patients had been avoiding at admission, giving them between 6 and
10 doses of a food at 15- to 30-minute intervals. They also initiated an intensive skin care and AD education program in the 96% of patients who had AD, noting that initial optimal clearing of the skin is essential to accurately assess the effects of food elimination and reintroduction on AD.

Commentary

This study puts into question the practice of relying on food-specific immunoassays in children with atopic disease, especially for foods other than the most common food allergens. For nearly 90% of the children described here, a food challenge under the supervision of an allergist led to a liberalized diet. So consider calling a pediatric allergist before restricting the diet of a child with AD because of immunoassay results.
-Michael Burke, MD