Atopic allergy and serum IgE in randomly selected eight-year-old children

The incidence of atopic allergy and serum IgE levels as well as specific IgE antibodies was studied in a randomly selected sample of 164 8-year-old children who were followed-up for 2 years. The total incidence of atopic disease was 18.9 per cent. Serum IgE levels were above + 2 s.d. for the age before the onset of atopic disease in seven of 11 children who developed an atopic disease during the observation period. The direct paper disc sandwich radioimmunoassay, PRIST, equalled the Phadebas IgE test for discriminating between atopy and non-atopy, but PRIST is preferred because of its simplicity. Actual or future atopic disease disease is most probable when the serum IgE is above the + 2 s.d. limit for age. Serum IgE levels below the geometrical mean for age are rarely found in atopic disease. An IgE determination with PRIST will give more discriminative information than the family history and is recommended for routine purposes when there is a history of possible atopic allergy in a child.