[Asthma and chronic obstructive bronchopneumopathy: differential diagnosis].

Asthma and COPD are common problems seen by general practitioners. They share several signs and symptoms, so that a differential diagnosis generally needs lung function testing, with at least a spirometry, either performed on several occasions, or completed by bronchodilation or non specific bronchoprovocation tests. Spirometry should become one of the tools used daily by a general practitioner.