[Occupational asthma: an experimental asthma. Apropos of isocyanate-induced asthma].
Isocyanate-induced occupational asthma is a model of experimental asthma related to the environment. Many of its features are identical with those of allergic asthma by sensitization to air-borne allergens. Exposure to isocyanate before the first symptoms of asthma varies from a few weeks to several years. The prevalence of isocyanate-induced asthma has been estimated at 5 to 25%. Atopy is found in less than 30% of the cases. A significant increase of HRBNS can be demonstrated in most patients, but it may be absent. It may also fluctuate with the working periods or after a bronchial provocation test with isocyanate. Elimination of this compound reduces the HRBNS level in only one quarter of the cases. Delayed or biphasic reactions are frequent: 30 to 60% depending of the authors. An early diagnosis followed by total elimination may result in complete cure, but more than 50% of the patients remain symptomatic and with HRBNS. An IgE-dependent mechanism can be demonstrated in about 20% of the cases. The course of isocyanate-induced asthma is interesting in that the same phenomena are probably observed in chronic asthma resulting from repeated exposures to environmental allergens.
Pauli
G
G
Service de Pneumologie, Hôpital Civil, Hôpitaux Universitaires de Strasbourg.
Kopferschmitt
M C
MC
Dietemann
A
A
Blaumeiser
M
M
Bessot
J C
JC
D001249:Asthma / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000175:diagnosis; D001985:Bronchial Provocation Tests; D006801:Humans; D017953:Isocyanates / Q000009:adverse effects*; D009784:Occupational Diseases / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D015995:Prevalence
D017953:Isocyanates
L'asthme professionnel: un asthme expérimental. A propos de l'asthme aux isocyanates.