PREDICTORS OF ATOPY IN NEWBORN BABIES

The capacity of laboratory tests and clinical signs to predict allergi c manifestations up to 18 months of age was assessed in 129 newborn ba bies, most of whom had family members with atopic disease. The paramet ers assessed included family history; skin dryness; erythema toxicum; skin reactivity to histamine and IgE levels; eosinophil counts; and pe ripheral white blood cell, leukocyte differential, and platelet counts in cord blood (CB). Erythema toxicum and white blood cell and platele t counts were of no value as predictors of allergy. The sensitivity of family history, skin dryness, and sensitivity to histamine, as well a s IgE levels and eosinophil counts, varied 25-79% and the specificity 40-74%. The efficiency was never higher than 58%. Logistic regression, applied in order to evaluate the joint predictive power of the five p arameters, showed a P value of <0.001. The estimated probability for a topy before 18 months of age was 0.33 for neonates with normal skin te xture, a CB IgE of less than 0.5 kU/l, and a history of fewer than two family members with atopy. The probability increased to 0.89 for babi es with a dry skin, a history of two or more atopic family members, an d a CB IgE of greater than or equal to 0.5 kU/l. In conclusion, not on e parameter nor any combination of them seems suitable for general scr eening. However, a combination of family history and CB IgE and skin a ssessment may be used to identify babies at high risk of allergy for p articipation in prevention studies.