 - Asthma is defined as a chronic inflammatory disorder, leading to recurrent episodes of wheezing, breathlessness, chest tightness, andor coughing, based on variable airway obstruction 18. Children with docter-diagnosed asthma known at the department of Paediatric Pulmonology, were recruited from the University Hospital Maastricht. Atopic and not atopic asthmatic children were allowed; treatment with inhalation corticosteroïd ICS was not obliged. 