MITE ALLERGEN CONTENT IN MATTRESS DUST OF DERMATOPHAGOIDES-ALLERGIC ASTHMATICS RHINITICS AND MATCHED CONTROLS

It has been suggested that the mites Dermatophagoides pteronyssinus an d D. farinae are important indoor environmental factors facilitating b oth the sensitization of atopic subjects and asthmatic attacks of hous e dust-sensitive patients. Contradictory results have been reported ab out the current exposure to mites or their allergens among patients an d control groups of atopic or non-atopic subjects. In order to determi ne whether there is a difference in mite exposure levels between D. pt eronyssinus-sensitized asthmatics and/or rhinitis and control subjects we considered a case-control study of 70 patients with asthma and/or rhinitis and positive skin test reactions to D. pteronyssinus and twic e as many control subjects who were matched as to age and sex. The fir st control subject for each patient was an immediate neighbour of the patient and the second was a patient arbitrarily chosen among hospital ized patients. Mite allergen exposure was measured in mattress dust co llected under standardized conditions, by measuring Der p I + Der f I content and by performing a semiquantitative guanine determination (Ac arex-test(R)). The content of Der p I and Derf I was very high both in the homes of patients and those of healthy individuals: 69% of the to tal samples contained more than 10 mug Derp I + Der f I/g of dust. The re was no significant difference between cases and controls with respe ct to Der p 1, Der f I, Der p I + Der f I content and Acarex(R) class distributions. The calculated odds-ratios associated with the Acarex t est(R) and the mite allergens did not differ significantly from the le vel 1.0. Our findings show that in a Rhine valley city such as Strasbo urg with a high mite allergen load there is no difference in mite expo sure between D. pteronyssinus-sensitized patients and controls who can be considered not to differ from the general population with respect to atopy.