IgE values and T-lymphocyte subsets in children with atopic eczema/dermatitis syndrome

High levels of IgE and IgE-mediated reactions represent a typical finding in patients with atopic eczema/dermatitis syndrome (AEDS). However, 10-30% of patients usually do not show any increase of total blood IgE levels and any detectable specific IgE sensitization. We performed this study to evaluate the difference of T-lymphocyte subsets in AEDS patients with high or normal IgE values. We enrolled 21 children with AEDS who were at least two years of age (8 boys and 13 girls, aged 2-13 years) and 20 children as control cases with the same age and sex. These patients were classified as IgE-associated AEDS or not IgE-associated AEDS syndrome according to their IgE levels. We used monoclonal antibodies against CD3 (T cells), CD4 (T-helper cells), CD8 (T-cytotoxic cells), CD 19 (B cells), CD56 and CD16 (natural killer cells), CD3/HLA-DR (activated T cells), CD45Ra in CD4 (naive lymphocytes), CD25 (interleukin-2 receptor), CD57 in CD3 (suppressor/cytotoxic), and CD5 in CD20 (Becton Dickinson, Mountain View, CA). The severity of atopic dermatitis (AD) was determined according to the Scoring Atopic Dermatitis (SCORAD) index. Moreover, we checked the levels of peripheral blood eosinophils and of total and specific IgE for a panel of inhalant and food allergens. We found that the CD8+ level was significantly lower and the CD4/CD8 ratio was significantly higher than in healthy cases. Moreover, patients with not IgE associated AEDS (aAD) showed CD4+ levels significantly higher than IgE aAD patients and healthy controls. We found no difference of the SCORAD index in the two groups but there was an inverse relationship between this index and CD4/CD8 ratio. We did not find any correlation between IgE levels and the SCORAD index between eosinophils and SCORAD index or between age and IgE values. A decrease of CD8+ circulating T cells and an increase of the CD4/CD8 ratio are peculiar findings in AEDS patients with either high or normal IgE values.