[Involvement of distal airways in asthma: lessons from pediatric cohorts].

INTRODUCTION

Prospective studies of paediatric cohorts contribute to our knowledge of changes in pulmonary function in children with asthma.

STATE OF THE ART: Asthma is associated with a significant impairment of the distal airways which is more pronounced when asthma has started early, before 5 years of age, or when asthma is persistent. In utero exposure to tobacco smoke allergenic sensitization and persistent bronchial hyperresponsiveness are the main factors associated with an unfavourable respiratory function outcome. This impairment may persist despite the disappearance of symptoms. Distal airway alterations are also poorly responsive to conventional inhaled corticosteroid therapy. This could be due to early remodelling phenomenon or non-optimal deposition of the drugs on distal airways.

PERSPECTIVES AND

CONCLUSIONS

The medium and long term clinical implications of distal airway involvement in paediatric asthma and the impact of treatment need to be evaluated.