BRONCHIOLITIS OBLITERANS IN AN ANIMAL FEED WORKER

A nonsmoking animal feed worker developed severe irreversible airflow obstruction during a 2-year occupational exposure to organic matter, m icroorganisms, proteolytic enzymes, and both amorphous and synthetic s ilicates. Her pulmonary dysfunction failed to improve despite removal from the workplace and treatment with bronchodilators and corticostero ids. Open lung biopsy demonstrated peribronchiolar inflammation, scarr ing within the small airways, and neolumen formation, findings consist ent with bronchiolitis obliterans. Energy dispersive analysis of both the bronchoalveolar lavage fluid as well as the biopsy specimens revea led the presence of silicate particles, suggesting a potential link be tween the silica exposure and the pathologic findings. This case sugge sts bronchiolitis obliterans can occur as a consequence of occupationa l exposure in the animal feed industry. In addition, this entity shoul d henceforth be considered when evaluating symptomatic patients with e xposure to amorphous and synthetic silicates. (C) 1995 Wiley-Liss, Inc .