Higher incidence of Dermatophagoides pteronyssinus allergy in children of Taipei city than in children of rural areas.

BACKGROUND AND PURPOSE House dust mites are the most common cause of sensitization in wheezing children in most parts of the world. The aim of this study was to investigate prevalence of sensitization and the levels of specific immunoglobulin E (IgE) to Dermatophagoides pteronyssinus (Der p) in wheezing children in Taipei city and central rural Taiwan. METHODS A total of 3546 children were enrolled in this study. Children were grouped into those living in Taipei city (n = 1340) and those residing in the rural part of central Taiwan (2206). The prevalence of sensitization and level of specific IgE antibody to Der p and cockroach were analyzed by age and geographic area. RESULTS The results showed significantly higher sensitization rates and mean specific IgE levels to Der p with increasing age of patients in both Taipei city and rural central Taiwan. In addition, children from Taipei city had a significantly higher average sensitization rate of Der p than rural children (p<0.05). The proportion of children sensitized to cockroach increased with age both in Taipei city and central rural Taiwan, but the specific IgE levels to cockroach were not statistically different between the 2 groups (p=0.061). CONCLUSIONS Sensitivity to aeroallergens varies with age and with geographical location (city vs rural) in asthmatic children. Circulating IgE antibodies against Der p were common at all ages. Cockroach allergen is also associated with recurrent wheezing in Taiwan. Avoidance of indoor aeroallergens such as Der p and cockroach allergen should be an important component in plans for the management of recurrent wheezing.