Sensitization to Blomia tropicalis and Dermatophagoides pteronyssinus - A comparative study between Singapore and Taiwan

Blomia tropicalis (Bt) and Dermatophagoides pteronyssinus (Dp) are the pred ominant domestic mites species in Singapore and Taiwan. This study aims to characterize and compare the mite sensitization profiles in both countries. Skin prick tests were performed on 203 Singaporeans with Dp and Bt crude e xtracts. In vitro IgE and IgG4 reactivity to extracts and specific allergen s (Der p 1, Der p 2 Der p 5 and Blo t 5) were determined by immunoassays. A pproximately 91% of the tested Singaporeans were skin test positive for bot h Bt and Dp. Both populations share similar frequencies of in vitro IgE rea ctivity to all the allergens tested, but they differ in the pattern and mag nitude of allergen sensitization. Although Der p 1, Der p 2 and Blo t5 are major sensitizing allergens in both countries, Blo t 5 is a more potent one in Singapore, probably reflecting the high level of exposure to Bt. The un ique major Bt and Dp allergens should be included for precise diagnosis and effective immune-therapeutic treatment of mite allergy in both countries.