Methods
Clinical evaluation, based on patient reported outcomes (Asthma Control Questionnaire 5 (ACQ5) and Asthma Control Test (ACT), was performed. Pulmonary function tests and FeNO have been used to assess airway function and inflammation, respectively. Sino-nasal Outcome Test 22 (SNOT-22) has been used to score upper airway involvement. Sensitization to Staphylococcus aureus enterotoxins was detected by ImmunoCAP (ThermoFisher Scientific/Phadia, Uppsala, Sweden).