[A case of bronchiolitis possibly associated with inhalation of hard metal]

A 36-year-old man, a worker exposed to tungsten and cobalt compounds, was admitted because of chest bilateral micronodular shadow with chronic cough and sputum. Chronic sinusitis, mild hypoxemia, obstructive respiratory impairment and chest radiological findings fulfilled the Japanese diagnostic criteria for diffuse panbronchiolitis, while atypical bronchoalveolar lavage fluid and pathological findings were seen. The surgical lung biopsy specimens showed patchy centrilobular inflammatory change with monocytic infiltrations and particulate deposition inside the area of bronchiolitis, but neither tungsten nor cobalt was found. Treatment with a macrolide antibiotic had no effect on the patient's symptoms, hypoxemia and lung function, suggesting bronchiolitis associated with inhalation of hard metal.