SERUM IMMUNOGLOBULIN E IN ATOPIC AND NON‐ATOPIC CHILDREN AGED 6 MONTHS TO 5 YEARS

Abstract

To obtain serum IgE reference values for small children the total serum IgE concentrations at the ages of 6 mo., 1, 3 and 5 yr were measured in 66 healthy, non-atopic children who were followed from birth to 5 yr of age. From this reference group children with symptoms or signs of atopy during the follow-up period, and children with blood or nasal smear eosinophilia or positive skin prick tests were excluded. Serum IgE levels in groups of children having latent atopy, symptomatic atopy or severe atopic disease were studied. In the definition of reference values the upper limit of normal should be replaced by a zone of uncertainty, lying between the 95th-97.5th percentiles. Serum IgE is a useful test with high specificity but low sensitivity in the differentiation between atopy and non-atopy. High levels suggest atopy, while normal or low values yield little information. A normal serum IgE level does not necessarily exclude atopic disease.