[Screening in asthma].

One of the most important characteristics of asthma is its association with non specific bronchial hyperresponsiveness. This is diagnosed by histamine bronchial challenge tests. This latter is an easy procedure but requires a precise and standardized methodology. We have analysed, in a large group of bronchial challenge tests (n = 162) the clinical correlations with bronchial response to histamine. Our conclusions are in agreement with several recent literature, and may be summarised as follows: 1. more than 10% of patients, clinically considered as asthmatics do not show bronchial hyperresponsiveness and probably will not benefit from bronchodilators; 2. several aspecific respiratory symptoms (cough, chest tightness, blocked nose and sneezing, recurrent bronchitis, etc...) are frequently associated with bronchial hyperresponsiveness and should be considered as asthmatic manifestations. To conclude, we recommend to realise a histamine non specific challenge test in all cases of clinical suspicion of asthma (with normal lung function at basal state) and in all subjects presenting chest symptoms of uncertain etiology.