A case of hard metal lung disease resembling a hypersensitive pneumonia in radiological images.

A 42-year-old man was admitted to our hospital because of exertional dyspnea. He had worked as a metal grinder for 3 years, but had quit his job 1 month before admission. Chest radiography and high-resolution computed tomography showed diffuse ground-glass opacities like hypersensitivity pneumonitis shadows. The results of high-energy dispersion X-ray microanalysis indicated that the patient had hard metal pneumoconiosis associated with tungsten. Since the histological changes distributed terminal to respiratory bronchiole and surrounding alveoli, and macrophages engulfed black granules within the alveoli, in absence of giant cells, we considered this case to be a type of hypersensitivity pneumonitis of hard metal lung.