Pulmonary silicatosis. A case diagnosed by needle-aspiration biopsy and energy-dispersive x-ray analysis.

The diagnosis of silicatosis was made by observing birefringent crystals in needle-aspiration biopsy specimens of bilateral basilar pulmonary masses in a clay worker, initially suspected of having metastatic neoplasm. Subsequently the crystals were examined by scanning electron microscopy and energy-dispersive x-ray analysis, which gave supportive evidence for their silicate composition. This experience indicates that needle-aspiration biopsy in conjunction with scanning electron microscopy and energy-dispersive x-ray analysis may be used in the diagnosis of benign pulmonary diseases, especially those of the inhalational fibrogenic variety.