For a study, it was determined that new material on occupational constrictive bronchiolitis from 2009 to 2012 called into question the textbook depictions of the condition, which was previously assumed to be restricted to fixed airflow restriction, potentially caused by accidental overexposure to various hazardous chemicals. A more typical presentation was the indolent progression of dyspnea without a documented harmful exposure. Biopsy-confirmed case series of constrictive bronchiolitis from US soldiers, Iranian survivors of sulfur mustard gassing, hospital-based studies, and flavoring-related cases showed that patients with indolent constrictive bronchiolitis can have normal spirometry or restrictive or obstructive abnormalities. High-resolution computed tomography investigations on expiratory films might be either normal or show air-trapping and mosaic attenuation. In the absence of noninvasive abnormalities, the diagnosis in dyspneic patients necessitated thoracoscopic biopsies in contexts where the danger of exposure had not been identified. Many employees who were suffering from occupational constrictive bronchiolitis improved after avoiding exposures that caused bronchiolar epithelial necrosis.

Regardless of spirometric or radiologic evidence, clinicians must have a high index of suspicion for constrictive bronchiolitis in young patients with quickly developing exertional dyspnea. To give guidelines for safeguarding workers at the risk of this mainly irreversible lung illness, fresh causes and exposure-response relationships for recognized causes must be identified.