Prognostic factors in patients with reactive dye or isocyanate-induced occupational asthma after avoidance of causative agents.
- Author:
Sang Fok LEE
;
Yoon Keun KIM
;
Woo Kyung KIM
;
Jee Woong SON
;
Sang Heon CHO
;
Kyung Up MIN
;
You Young KIM
- Publication Type:Original Article
- Keywords:
occupational asthma;
prognosis;
resctive dye;
isocyanates
- MeSH:
Airway Obstruction;
Asthma;
Asthma, Occupational*;
Bronchial Provocation Tests;
Diagnosis;
Follow-Up Studies;
Humans;
Isocyanates;
Lung;
Methacholine Chloride;
Prognosis;
Surveys and Questionnaires
- From:Journal of Asthma, Allergy and Clinical Immunology
1999;19(3):484-491
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Although occupational asthma is defined as a reversible airway obstruction causally related to exposure in the working environment, many occupational asthmatics complain of asthmatic symptoms despite avoidance of the causative agent. Subjects and methods. Twenty-nine patients with occupational asthma who had been confirmed by specific bronchial challenge with reactive dye or isocyanates and had avoided the causative agent for at least 6 months were included in this study. A questionnaire about asthmatic symptoms and medication requirements, a lung functiontest, and a methacholine bronchial provocation test were performed. RESULTS: Asthmatic symptoms at follow-up were remitted in seven (41.2%) isocyanate-induced asthmatics, but none with reactive dye-induced asthma were remitted. At follow-up, the symptom-medication score and FEV1 were significantly improved in isocyanate-induced asthmatics than in those with reactive dye-induced asthma, but the geometric mean of PC20-methacholine was not different between the two groups. Among 17 isocyanate-induced asthmatics, a duration from symptom onset to avoidance was significantly shorter in the remission group than in the nonremission group, although the symptom-medication scores, FEV1 (% predictive value) and logPC20-methacholine at an initial diagnosis, and follow-up period defined as duration from avoidance to follow-up, showed no difference between the two groups. CONCLUSION: The outcome of occupational asthma may be determined by the causative agents and the duration from onset of asthmatic symptoms to avoidance.
