The role of bronchoalveolar lavage in quantifying inhaled particles in silicosis

Silicosis is a disease caused by inhalation and deposition of crystalline silica that produces a fibrous tissue reaction. Bronchoalveolar lavage is a noninvasive technique that allows identifying particles, thus characterizing exposure to mineral dust. The aim of this work was to study bronchoalveolar lavage as a mean of estimating the amount of alveolar particles in different forms of silicosis. Bronchoalveolar lavage was carried out in 27 silicotic patients with simple (n = 12), complicated (n = 13), and acute (n = 2) forms of the disease and 7 healthy individuals as a control group. Macrophages were scored enumerating the percentage of cells with particles by polarizing light microscopy. Silicotic patients showed a marked increase in BAL cell particles compared to control population, however, relating simple to complicated silicosis, no significant difference was observed. In acute silicotic patients with massive silica dust exposure, more than 70% of BAL alveolar macrophages contained dust particles. When duration of exposure and retirement from work were evaluated, an inverse correlation between duration of exposure and the amount of alveolar dust, and a tendency to a smaller involvement on macrophages with the greater period of retirement from work were observed. These results suggest that particle analysis in BAL may be important in order to establish the nature and intensity of exposure.