Disagreement between Skin Prick Tests and Specific IgE in Early Childhood.

BACKGROUND

Accurate diagnosis of allergic sensitization is essential in clinical practice and allergy research, and the choice of assessment method may have an important impact. The PASTURE study (Protection against Allergy: Study of Rural Environment) examines the influence of exposure to a dairy farm environment on the occurrence of allergy in a cohort of rural European children from birth to 10 years. The aim of our study was to analyze agreement between skin prick tests (SPTs), to aeroallergens and food allergens, and specific IgE and to evaluate the association of SPT with atopic dermatitis in the 204 French children of the PASTURE study.

METHODS

SPT, atopic dermatitis assessment, and specific IgE measurements were performed at 1, 4.5, and 6 years.

RESULTS

A total of 137 children attended all three visits. The agreement between SPTs and specific IgE was poor except for perennial aeroallergens at 6 years and for an IgE cutoff greater than 0.7 IU/ml (κ = 0.69, 0.5202 - 0.8621). The prevalence of positive SPTs increased with age. Positive SPTs were transient at 1 year, whereas they were persistent between 4.5 and 6 years. Positive SPTs at 1 year were predictive of the occurrence of atopic dermatitis during follow-up.

CONCLUSION

SPTs did not have good agreement with serum-specific IgE in early childhood. Both tests (SPT and specific IgE) should be used. Skin allergenic reactivity increased with age and was transient at 1 year but associated with the occurrence of atopic dermatitis.