[Pulmonary siderosis: report of a case].

Pulmonary siderosis is one kind of pneumoconiosis caused by the long term inhalation of iron dust. It occurs in a number of occupations including steel rolling and grinding, welding, polishing, casting, boiler scaling, iron ore mining and emery working. Here we report a case of pulmonary siderosis. A 49-year-old male who had worked in an iron foundry for 30 years was admitted because diffuse micronodular lesions were seen in both lung fields on a routine chest radiographic study. A pulmonary function test disclosed a mildly restrictive ventilatory defect. Transbronchial lung biopsy revealed a significant amount of iron dust deposited within a fibrous nodule by which confirmed the diagnosis of pulmonary siderosis.