Bronchial hyperresponsiveness consists in excessive response to bronchial stimuli.Bronchial challenge test is used to confirm/exclude asthma (metacholine or histamine).Protection are used to avoid passive exposure of the technicians performing the test, despite the absence of evidence that they could develop a bronchoconstriction even if they suffer from BHR.The purpose of the study is to determine if patients with a high level of bronchial hyperreactivity and exposed passively to histamine during a bronchial challenge, are developing a bronchoconstriction, when placed in the same conditions that the technicians performing these tests.

Bronchial hyperresponsiveness (BHR) consists in excessive response to bronchial stimuli.Bronchial challenge test is used to confirm/exclude asthma.BHR is also present in other diseases such as allergic rhinitis, Chronic Obstructive pulmonary disease,heart failure..

Thes test is performed with metacholine or histamine with spirometric documented response to incremental doses.Protection are used to avoid passive exposure of the technicians performing the test, despite the absence of evidence that they could develop a bronchoconstriction if they suffer from BHR.

The purpose of the study is to determine if patients, newly diagnosed with a high level of bronchial hyperreactivity and exposed passively to histamine during a bronchial challenge, are reacting to histamine when placed in the same conditions that the technicians performing these tests.

Inclusion Criteria:

• adult patients with positive histamine challenge test (first dose)

Exclusion Criteria:

• other active respiratory disease