A 38-year-old sandblasting worker presents with progressive dyspnoea and productive cough. Chest X-ray reveals bilateral upper-zone nodular opacities with 'eggshell calcification' of hilar lymph nodes. Pulmonary function tests show a mixed restrictive-obstructive pattern. The causative occupational exposure and the pathological lesion is:
- A Free crystalline silica (SiO₂) — silicotic nodule with concentric collagen ✓
- B Asbestos fibres — pleural plaques and mesothelioma
- C Coal dust — coal macule with focal emphysema
- D Beryllium — non-caseating granulomas (berylliosis)
Explanation
Sandblasting is among the highest-risk occupations for silicosis due to intense exposure to fine respirable particles of free crystalline silica (quartz). The pathological hallmark of silicosis is the silicotic nodule — a concentrically arranged 'onion-skin' whorled collagen nodule with a central necrotic zone, found predominantly in upper lobes. Eggshell calcification of hilar lymph nodes is pathognomonic of silicosis. Coal worker's pneumoconiosis shows coal macules without eggshell calcification. Asbestos causes pleural plaques and interstitial fibrosis (asbestosis). Berylliosis mimics sarcoidosis with non-caseating granulomas.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.