[Bronchoalveolar lavage in pneumoconiosis of coal miners. Cytologic aspects].

The cytological characteristics of broncho-alveolar fluid were studied in 94 coal workers and six subjects exposed to varied risks of silicosis. In coal worker's pneumoconiosis with the usual micronodular or nodular type, there was a significant increase in the cellularity of the peripheral airways compared to non-exposed controls, making allowances for smoking habits. There were no striking changes in the white cell count nor any correlation with the possible elevation in the serum angiotensin I-enzyme conversion level. On the other hand a striking elevation of the alveolar lymphocyte count was noted in three cases with rapidly developing silicosis. Where there was the co-existence of another disorder (connective tissue disorders, sarcoid, extrinsic allergic alveolitis, radiation lung or diffuse interstitial fibrosis) the anomalies noted were those occurring during the progress of the associated disease. At the time of collection the alveolar macrophages in the dust exposed subjects showed a similar vitality to these observed in control subjects. After 24 hours of observation " in vitro ", the vitality of the cells and their phagocytic and bactericidal activity was markedly diminished.