A 45-year-old sandblasting worker presents with progressive dyspnoea and X-ray showing bilateral upper-zone nodular opacities with eggshell calcification of hilar lymph nodes. The most specific radiological finding that differentiates his occupational disease from sarcoidosis is:
- A Bilateral upper-zone nodular shadows
- B Pleural thickening
- C Eggshell calcification of hilar lymph nodes ✓
- D Progressive massive fibrosis on CT
Correct answer: C. Eggshell calcification of hilar lymph nodes
Explanation
Eggshell calcification of hilar/mediastinal lymph nodes is pathognomonic of silicosis (or rarely coal worker's pneumoconiosis) and does not occur in sarcoidosis. It represents peripheral calcification of lymph nodes due to silica-induced fibrosis. Bilateral upper-zone nodular opacities occur in both. Progressive massive fibrosis can complicate both silicosis and coal-workers' pneumoconiosis but is not specific. Pleural thickening is more characteristic of asbestosis.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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