RESUMO
BACKGROUND: There are documented molecular homologies between mites from the same group, but intergroup characteristics are not. Although mites share the same taxonomic order, there are species antigenically distinct. At the present we dont know clearly the differences in cutaneous reactivity among several house dust mites species. OBJETIVE: to estimate the correlation of skin reactivity to Dermatophagoides pteronyssinus and Dermatophagoides farinae antigens with that of Blomia tropicalis in patients with allergic rhinitis and asthma. METHODS: a cross sectional, observational, prolective and interpretive study was performed in patients of both genders, aged 2 to 58 with allergic rhinitis and asthma. All patients underwent skin prick tests with allergenic extracts. RESULTS: One hundred and ten patients were included, with an age average of 24.1 years; 50% were males. There were positive skin tests with mites in 59% of the patients, 24.5% for Blomia t; 10% for D. pteronyssinus plus Blomia t. and 7.29% for D. farinae plus Blomia t. The correlation of the skin reactivity between Dermatophagoides pteronyssinus and Blomia tropicalis (r= 0.36) and between Dermatophagoides farinae and Blomia tropicalis (r= 0.27), was not significant in both cases. CONCLUSIONS: We found that most patients with allergic rhinitis and asthma showed positive skin tests with the mite extracts tested. There is a weak correlation between both species of Dermatophagoides and Blomia tropicalis.
