Hard metal interstitial lung disease (HM-ILD) is a rare form of interstitial lung disease caused by aerosolized particulates containing cobalt inhaled during the manufacture or grinding of hard metal. The high-resolution computed tomography (HRCT) appearance of HM-ILD includes reticulation, traction bronchiectasis, and large peripheral cystic spaces in a mid and upper lung distribution. This appearance, along with a consistent occupational exposure, should specifically suggest the diagnosis of HM-ILD.
From *Department of Radiology, †Division of Pulmonary and Critical Care Medicine, Department of Medicine, and ‡Department of Pathology, University of California, San Francisco, CA.
Address correspondence and reprint requests to Michael B. Gotway, M.D., Thoracic Imaging Section, University of California, San Francisco, San Francisco General Hospital, Room 1X 55A, Box 1325, 1001 Potrero Avenue, Department of Radiology, San Francisco, CA 94110. E-mail: firstname.lastname@example.org