title: Bronchial challenge to house dust can induce immediate bronchoconstriction in allergic asthmatic patients.
abstract: The goal of the study was to evaluate whether natural exposure to house dust could elicit immediate bronchoconstriction. Two groups of asthmatic patients were studied: 12 asthmatics allergic to house dust mites and seven nonallergic asthmatics. The baseline FEV1 was similar in the two groups. Each subject was challenged through a nasal mask connected to nebulizer filled with house dust. Patients were randomly assigned to inhale dust with high or low Group I allergenic level. All allergic patients had an FEV1 drop larger than 20% of the baseline value. This drop was maximal at the 30th minute after challenge. FEV1 remained unchanged in nonallergic asthmatics. Allergic patients challenged with high Group I allergenic house dust (8.4 micrograms/g) had a mean FEV1 drop larger (P less than .01) than those challenged with the low Group I allergenic house dust (0.66 micrograms/g). Late asthmatic reactions were found in only two patients who were challenged with the high Group I allergenic house dust. These two patients had immediate FEV1 drops greater than 50% of the baseline value. Occurrence of symptoms during the test and the drop in FEV1 were correlated (r = .3; P less than .05). Natural exposure to house dust can induce immediate bronchial in allergic asthmatics in a dose-dependent manner.
authors: Department of Respiratory Diseases, St. Marguerite Hospital, Marseille, France.
authors: L
authors: L
authors: M'Raihi
authors: D
authors: D
authors: Charpin
authors: M
authors: M
authors: Thibaudon
authors: D
authors: D
authors: Vervloet
mesh_terms: D000328:Adult; D000485:Allergens / Q000494:pharmacology; D000818:Animals; D001249:Asthma / Q000209:etiology* / Q000503:physiopathology; D001980:Bronchi / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004391:Dust / Q000009:adverse effects*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D008925:Mites; D013997:Time Factors
chemical_list: D000485:Allergens; D004391:Dust