Prevalence and role of serum IgE antibodies to the Staphylococcus aureus-derived superantigens SEA and SEB in children with atopic dermatitis

Background: The skin of patients with atopic dermatitis exhibits a striking susceptibility to colonization and infection with Staphylococcus aureus. I n this contest it has been previously shown that S aureus-derived superanti gens could function as classic allergens, inducing production of functional ly relevant specific IgE antibodies. Objective: The aim of this study was to determine the prevalence and the ro le of circulating staphylococcal enterotoxin A (SEA)- and staphylococcal en terotoxin B (SEB)-specific IgE antibodies in children with atopic dermatiti s. Methods: In a cross-sectional study of 58 children with atopic dermatitis, the presence of IgE antibodies to SEA and SEE was correlated with the sever ity of the disease and the total and other unrelated allergen-specific IgE titers and density of colonization with S aureus strains on atopic skin and episodes of superficial S aureus skin infections. Results: Twenty of 58 children (34%) were sensitized to superantigens (45% to SEB, 10% to SEA, 45% to SEA and SEE). In this group, severity of atopic dermatitis and levels of specific IgE to food and air allergens were signif icantly higher. The degree of disease severity correlated to a higher exten t with the presence of SEA/SEB-specific antibodies than with total serum Ig E levels. Density of colonization with superantigen-secreting S aureus stra ins was higher in the superantigen IgE-positive group, Sixty-three percent of these children experienced repeated episodes of superficial S aureus ski n infections. Conclusions: Sensitization to S aureus-derived superantigens may be involve d in disease exacerbation. The presence of SEA/SEB-specific antibodies had additional explanatory value for disease severity and therefore may be help ful in the characterization of children with severe atopic dermatitis.