[Occupational asthma].

Background: Occupational asthma (OA) is a frequent work-related disease in industrialised countries. It often leads to severe social and medical consequences.

Two Types Of Oa: A distinction must be made between OA with a latency period, the origin of which is essentially allergic, and OA without a latency period or Reactive airways dysfunction syndrome (RADS), induced by acute inhalation of irritant substances.

Prevalence: This is currently estimated as one case of asthma of occupational origin in one adult out of ten. In many cases its diagnosis is missed because it is not systematically searched for.

Regarding Diagnosis: Diagnosis, initiated on the results of questioning, must be supported by immunological tests whenever possible and notably on functional respiratory explorations (longitudinal monitoring of peak flow or spirometry, repeated measurements of non-specific bronchial reactivity), which objectifies significant variations in the parameters measured and related to professional activity. Bronchial challenge tests specifically identify the causal agent, but such examinations are long, expensive, potentially dangerous and therefore cannot be used in routine.

Management Of Oa: Both social and medical, the management is aimed at stopping the exposure to the risk whilst protecting the person's employment. The declaration of occupational diseases is one of the principle measures of the medico-social care.