Study Syllabus for Classification of Radiographs of Pneumoconioses
Pathology Basis of Occupational Lung Disease
Lymph Node Silicosis
Lymph node involvement by silicotic nodules frequently accompanies pulmonary silicosis, and is often present as an isolated finding in exposed individuals with no radiologic or histologic stigmata of pulmonary silicosis. The morphology of nodules in lymph nodes is identical to those in the lung parenchyma. Extension of lesions beyond the capsule of the lymph node into the lung hilum can result in hilar fibrosis and bronchial stenosis. Peripheral calcification of silicotic lymph nodes may produce the classical radiographic appearance of “eggshell calcification” in approximately 10% of cases [Silicosis and Silicate Disease Committee 1988]. Erosion of calcified lymph nodes into adjacent airways is an infrequent cause of obstructive broncholithiasis [Cahill et al. 1992].