부산대학교 도서관

A 63-year-old male patient with hemoptysis was admitted to our hospital for treatment of hemostasis. Prolonged bronchial bleeding from the right upper and middle lobe bronchi was halted by embolization of the right bronchial artery after unsuccessful conservative treatments involving endobronchial tamponade(the wedge method). The chest X-ray film showed a mild increase of linear markings and faint nodular opacities in both lungs. He had been working in polishing both the hard metal alloy blades of many kinds of saws and the hard metal cutting edges of tools, and had inspired the dust powder for 20 years. The hard metals mainly consisted of tungsten, cobalt and a few other elements. The lung tissues obtained by trans-bronchial lung biopsy showed marked infiltration of lymphoid cells and also mild fibrosis in the peribronchial regions and lung parenchyma. An electron microscopy elemental analysis of the lesion demonstrated the presence of most of the metals found in the powder but not of the cobalt. We found numerous particles of the hard metal dust from the polished particulates. Thesewere as small as a few micron and were inspirable as far as the bronchiols. Inspired cobalt was considered to have disappeared from the lesion since it is highly soluble. He responded well to corticosteroid therapy and his chest discomfort disappeared.