The Changes of Allergic Sensitization with Age in Children with Allergic Rhinitis

Background and Objectives: Allergic disease in children has diverse characteristics & sensitization with age because of allergen, pathophysiologic and immunologic differences. There have been few reports regarding the changes of allergic sensitization with age in children in South Korea, so we aimed to find out these changes by CAP test. Materials and Methods: A total of 8994 children (6238 boys, 2756 girls, mean 10.5 years, range from 5 months to 18 years) with allergic rhinitis were subjected to this study. They were classified by age groups into ≤3, 4~6, 7~9, 10~12, 13~15 and 16~18 year-old. All children underwent the CAP test (Fluoroenzyme immunoassay) about two subtypes of house dust mites (D. pteronyssinus, D. farinae), cat, dog, tree mixture and weed mixture allergens. In addition, allergens were classified into indoor, outdoor, or both. We analyzed age-based differences according to the types of allergens. Also we analyzed the total IgE. Results: CAP test analysis of allergic rhinitis patients in children showed that the age group 10-12 had higher titer to house dust mite allergens (DP 18.40±27.64 U/ml, DF 30.56±27.62U/ml) than other groups and the highest degree of positive reaction to multiple allergens (p<0.001). Age under 10 groups (≤3, 4~6, 7~9) were revealed significant difference of D. pteronyssinus IgE titer among other groups (p<0.001). Age over 10 groups (10~12, 13~15, 16~18) showed difference with age under 10 year-old groups (p<0.001) but no difference in each other (p=1.0, 0.984, 0.967) with Kruskal-Wallis test and post-hoc Tukey test. Same results were obtained in the D. farinae test. Sensitization ratio to weed and tree allergens tended to increase with age, while sensitization ratio of cat and dog did not present significant differences according to age. Certain tendencies depending on types of allergens were found – sensitization by indoor allergens were high but did not indicate age-based differences, while sensitization by outdoor allergens tended to grow with age. In addition, total lgE presented difference between age under 7 groups (≤3, 4~6) and age over 7 groups (7~9, 10~12, 13~15, 16~18) with statistical significance (p<0.001) and increased with age in general, with boys showing significantly higher lgE titer than girls (p<0.001). Conclusion: The sensitization in children with allergic rhinitis was changed with age in some allergens by CAP test.