Comparative cross-sectional study. It will include 32 allergic and non-allergic asthma patients and 10 healthy volunteers. All patients will have an induced sputum, pulmonary function studies, FENO (exhaled fraction of nitric oxide), total and specific IgE measurement at d1 (the most common perennial pneumoallergen) in blood and induced sputum, as well as a prick skin test with standardized allergen extracts. Measurement of total IgE and IgE for d1 in induced sputum will be performed in the supernatant and by the ImmunoCAP (Phadia ThermoFisher Scientific) immunofluoroassay technique.
