Extraordinarily high serum IgE levels and consequences for atopic phenotypes.

Background: IgE plays a central role in allergic diseases. Recent studies have postulated an association between serum IgE levels and bronchial asthma.

Objective: To examine the differences of atopic phenotypes in a group of individuals with extraordinarily high serum IgE levels (>10,000 kU/L) compared with children with moderately elevated IgE levels (400-1,000 kU/L).

Methods: We investigated 20 children with serum IgE levels greater than 10,000 kU/L and compared them with 56 age-matched children with serum IgE levels of 400 to 1,000 kU/L regarding prevalences of atopic dermatitis, bronchial asthma, allergic rhinoconjunctivitis, allergic sensitization, and history of anaphylaxis.

Results: The mean eczema severity score as determined by the Severity Scoring of Atopic Dermatitis Index was 56 vs 18 (P < 0.003), and anaphylactic reactions were reported in 20% of the group with very high serum IgE levels vs 7% in the group with moderate levels (P < 0.02). Sensitization to both aeroallergens and food allergens was detected in 80% of the group with very high serum IgE levels vs 32% of the group with moderate levels (P < 0.001).

Conclusions: Our results indicate that children with very high serum IgE levels are at risk for anaphylactic reactions and more severe atopic dermatitis.