Diagnosis of asbestosis by transbronchial biopsy. A method to facilitate demonstration of ferruginous bodies.

The diagnosis of asbestos-associated pulmonary fibrosis was established in 3 patients by finding ferruginous bodies in transbronchial lung biopsies. Ferruginous bodies may be difficult to identify in histologic preparations when they are not oriented parallel to the plane of tissue section or when camouflaged by anthracotic pigment. We describe a simple method to enhance diagnostic sensitivity by digesting biopsy tissue and examining the filtered residue for ferruginous bodies.