[Limits in the evaluation of bronchial reactivity in children with asthma]

Bronchial hyperresponsiveness (BHR) reflects an exaggerated sensitivity of airways to pharmacologic and/or physical stimuli. Patients with symptomatic asthma often have a higher degree of BHR than nonasthmatics, even though BHR shows a variable relationship with the clinical expression of the disease and with medication requirements. Methods of bronchial challenge, initially developed in adults, are increasingly employed also in children. The Authors discuss the clinical significance of the evaluation of bronchial responsiveness in the diagnostic approach and follow-up of children with asthma. Some methodological aspects and limits of bronchial challenging in childhood are expecially addressed.