The patient was admitted and successfully treated with IV prednisolone and nebulized salbutamol and ipratropium bromide. After recovery, she was discharged from our hospital and treated with inhaled beclomethasone and fenoterol/ipratropium bromide as needed. Since she remained symptomatic and suffered from recurrent severe asthma exacerbations, treatment was gradually stepped up until she eventually used high-dose inhaled corticosteroids (beclomethasone fine particles, 3 × 400 μg; formoterol, 3 × 36 μg; tiotropium, 1 × 18 μg; fenoterol/ipratropium bromide, as needed; montelukast, oral theophylline, and oral prednisolone, 15 mg daily). During subsequent visits and hospitalizations, additional information was gathered. Again, a careful medical history revealed no suggestions for allergic triggers for any known allergens, including pet dander, grass pollen, house dust mites, and molds. In addition, there were no seasonal or work-related variations in asthma symptoms. Total serum IgE level was 491 IU/L (normal value, 115 IU/L), without specific IgE to any of the most common aeroallergens tested using the Phadia Immunocap (Phadia; Uppsala, Sweden) (eg, pet dander, grass, tree pollen, house dust mites, mugwort). Further, no specific IgE was detected to food allergens (eg, hen egg, cow milk, peanuts, fish, wheat, soy) or molds (eg, Aspergillus fumigatus, Penicillinum, Alternaria, and Cladosporium herbarum). Finally, the results of a skin-prick test for 17 common aeroallergens and 11 food allergens were negative. A bronchoscopy showed diffuse bronchial edema with a thickened basement membrane and diffuse tissue eosinophilia, compatible with asthma in airway wall biopsies (Fig 2). Since aspiration of gastric acid or bile could possibly enhance her asthma symptoms, treatment with high-dose proton pump inhibition and metoclopramide was started. Because of persistent symptoms, it was even decided to carry out a Roux-en-Y gastrojejunostomy to minimize the risk of bile aspiration. However, all these measures did not prevent the occurrence of frequent asthma exacerbations (ie, nine hospitalizations during 2005 and 2006). Some of her exacerbations were accompanied by respiratory insufficiency (pH, 7.28; Pco2, 8.6.kPa; and Po2, 5.7 kPa), which led to intubation and mechanical ventilation twice.