Factors influencing the occurrence of a late reaction to allergen challenge in atopic asthmatics.
Thirty extrinsic asthmatics were challenged by inhalation with Dermatophagoides pteronyssinus extract. In twenty-four an immediate reaction was observed and in sixteen this was followed by a late reaction. Those with late reactions tended to have more severe asthma but did not report greater sensitivity to housedust mite. The occurrence of a late reaction was not related to the degree of airways obstruction before challenge or to the intensity of the immediate reaction. Patients in whom the early reaction was induced by a low dose of inhaled antigen were those most likely to develop a late response. Results of histamine challenge testing suggested that this greater sensitivity of the airway might in part be due to greater non-specific bronchial reactivity.
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000008:administration & dosage*; D001249:Asthma / Q000276:immunology* / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D005541:Forced Expiratory Volume; D006801:Humans; D008875:Middle Aged; D008925:Mites / Q000276:immunology; D013997:Time Factors
D000485:Allergens