The aim of this study was to determine the level of two major mite allergens Dermatophagoides pteronyssinus (Der p 1) and Dermatophagoides farinae (Der f 1) in 30 urban homes in Zagreb, Croatia, using the enzyme immunoassay with two monoclonal antibodies which has been established as the reference method for indoor allergen analysis. Dust samples were taken by vacuuming a carpeted area and collected on cellulose filters. The ranges of Der p 1 and Der f 1 were (0.1-12.5) μg g-1 (median 0.32 μg g-1) and (0.1-31.2) μg g-1 (median 0.35 μg g-1), respectively. Der p 1 and Der f 1 (>2 μg g-1) associated with increased risk of sensitization to mite allergens were found in approximately 16% homes for each allergen. The sum of allergen (Der p 1 + Der f 1) exceeded the lower threshold in 27% of homes. Analytical evaluation of the ELISA assay showed satisfactory results for precision (intra-assay CV <6.9%, inter-assay CV<13.3%), accuracy (91% to 93%), and sensitivity (2 ng mL-1).
The ELISA assay for the measurement of dust mite allergens demonstrated very good analytical characteristics for routine laboratory use, and will provide the essential basis for our future studies of various indoor allergens.
