[Chronic course of reactive bronchial dysfunction syndrome. Apropos of 6 further cases]

The reactive airways dysfunction syndrome (RADS) occurs as a persistent bronchial hyper-reactivity with asthmatic-type dyspnoea and occurs after a single and massive inhalation of irritant gases, smoke or vapours, in subjects who had previously had no respiratory disease. We report six cases in patients without any previous asthmatic history or history of atopy who had developed RADS after being exposed to different irritants. The symptoms evolved over 5-84 months after the initial accident. Only moderate airflow obstruction was found, but all subjects had bronchial hyper-reactivity to methacholine. A bronchial biopsy was performed in a patient and this showed moderate sub-epithelial mononuclear inflammatory infiltrate. A specific feature of this syndrome is the facility to inaugurate a susceptibility to asthma after the initial accident and for this to progress of its own accord with secondary aggravation, even in the absence of new exposure to the irritating agent. Its frequency is probably under-estimated because it remains little known in France. It is very important both to recognise and notify inhalational accidents at work to be able, should the nedd arise, to identify the worker and to enable a move to a different job if necessary.