[Etiological diagnosis of cough].

The assessment of cough starts with a search for possible causes, the commonest of which (acute or chronic inflammation of the upper airways, acute bronchial inflammation, smoking, asthma) are usually suggested by history and clinical examination. In chronic cases, where the chest X-ray is normal, the diagnosis must differentiate between ENT inflammation, asthma, post-infectious bronchial hyperresponsiveness and gastroesophageal reflux. Appropriate treatment can be administered solely when the most probable etiology has been determined.