[Challenge provocation tests and nonspecific bronchial hyperreactivity in occupational asthma].

The aim of the study is to determine the interest of realistic challenge (nasal and bronchial) in occupational respiratory symptoms appearing during work. 75 patients were included in the study. The protocol included prick tests, measuring total and specific IgE, spirometry and metacholine test to assess bronchial hyperreactivity (BHR), realistic challenge by rhinomanometry and plethysmography measuring NR (nasal resistance) and RWA (Airway resistance). The test was considered positive if the RWA and/or NR were increased by 100%. 68% of the tests were positives in rhinomanometry and/or plethysmography. There is an BHR in 68% cases of occupational asthma. There is a quite strong correlation between the positivity of the realistic tests and the existence of a non specific BHR.