Exposure to indoor allergens in homes of patients with asthma and/or rhinitis in southeast Brazil: effect of mattress and pillow covers on mite allergen levels.
BACKGROUND
Exposure and sensitization to indoor allergens have been associated with the development of asthma and other allergic diseases in many parts of the world. It is important to establish the degree of exposure, and to evaluate whether allergen control measures are effective in a particular area.


METHODS
Concentrations of major allergens of mites, cockroach, cat and dog were measured in dust samples from homes of 24 mite-allergic patients living in Ribeirão Preto, Brazil. Allergen concentrations were quantitated by monoclonal antibody-based ELISA. Mite-impermeable mattress and pillow covers were applied to beds in the homes of 19 of the 24 patients, and group 1 mite allergen levels were measured 1 and 6 months following intervention.


RESULTS
Patients were exposed to high concentrations of mite allergens in their homes. 87.5% of the homes presented concentrations of group 1 allergens >10 microg/g of dust in at least one site. Cockroach allergen concentrations were low in most samples. Dog allergen concentrations were significantly higher in homes with dogs as compared to those without dogs. Mean concentrations of cat allergen were 0.1 microg/g. Mite allergen concentrations in bedding samples dropped from 24 microg/g at baseline to 0.9 and 1.0 microg/g, respectively, 1 and 6 months following encasement of mattresses and pillows.


CONCLUSIONS
Significant mite allergen reduction can be achieved in an area of high degree of exposure to mite allergens. Further studies evaluating the effect of this reduction on symptoms and airway inflammation will be necessary to establish the effectiveness of mite avoidance measures in our area.
Tobias
Kátia R C
KR
Department of Pediatrics, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
Ferriani
Virginia P L
VP
Chapman
Martin D
MD
Arruda
L Karla
LK
D000293:Adolescent; D000328:Adult; D016902:Air Pollution, Indoor / Q000517:prevention & control; D000485:Allergens / Q000276:immunology; D039741:Antigens, Dermatophagoides / Q000276:immunology; D052179:Antigens, Plant; D060829:Arthropod Proteins; D001249:Asthma / Q000276:immunology* / Q000517:prevention & control; D001512:Bedding and Linens; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D003546:Cysteine Endopeptidases; D004391:Dust / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D039981:Pyroglyphidae / Q000276:immunology*; D011897:Random Allocation; D012221:Rhinitis, Allergic, Perennial / Q000276:immunology* / Q000517:prevention & control
D000485:Allergens; D039741:Antigens, Dermatophagoides; D052179:Antigens, Plant; D060829:Arthropod Proteins; D004391:Dust; C091462:allergen Can f I; D003546:Cysteine Endopeptidases; C451159:Dermatophagoides farinae antigen f 1; C451162:Dermatophagoides pteronyssinus antigen p 1