Diagnosing occupational asthma: insight from induced sputum.

The diagnosis of occupational asthma needs to be made objectively using as many criteria as possible. The latter include laboratory exposure tests with occupational a gent(s), which are only available in specialized centers. Another approach is to monitor peak expiratory flow (PEF) and (or) methacholine airway responsiveness during periods at work and away from work. However, these measurements are open to misinterpretation when they are not optimally performed. Airway inflammation is one of the main characteristics of asthma. Induced sputum, a non-invasive method to assess airway inflammation, has been Successfully used in the management of asthma. However, airway inflammation is seldom assessed during the investigation of occupational asthma. This article reviews the studies that have investigated and characterized the changes in Sputum Cell Counts occurring in Subjects with occupational asthma after exposure to occupational agents in the laboratory, or at the workplace to assess to place of induced sputum in the investigation of occupational asthma.