RESUMEN
Mite surveys in Thailand indicated that Dermatophagoides pteronyssinus (Dp) is predominant, but so far there were no data available on Blomia tropicalis (Bt), which is prevalent in the Asia Pacific region. Skin prick testing (SPT) was performed in 40 atopic children, 45 atopic adults and 17 non-atopic volunteers. Skin reactions to Dp were found in 25/40 (62.5%) and 23/45 (51.1%); skin reactions to Bt were found in 15/40 (37.5%) and 18/45 (40%) in atopic children and adults, respectively. SPT to the major sensitizing allergens Der p 1, Der p 2, Der p 5, and Blo t 5 showed positive results in 14/40 (35%), 12/40 (30%), 1/40 (2.5%) and 4/40 (10%) of atopic children, and in 12/45 (26.7%), 13/45 (28.9%), 5/45 (11.1%), 6/45 (13.3%) of atopic adults, respectively. The results indicate that Dp is one of the major sources of allergy, while Bt is a minor one and that Der p 1 and Der p 2 are important mite allergens in Chiang Mai, Thailand.