Question
55-year-old non-smoker presented with progressive exertional shortness of breath for 3 years.He was previously a construction site worker for more than 20 years. Physical examination was unremarkable except that the patient was tachypnoeic.
Laboratory investigations were essentially normal and lung function test revealed a constrictive pattern. A CXR was performed.What is the most possible diagnosis?
A. Mediatinal Lymphadenopathy
B. Silicosis
C. Pulmonary Tuberculosis
D. Bronchogenic Carcinoma
Show Answer
|
Correct Answer » B
Explanation
|
|
Ans:B. Silicosis.
Image shows:Chest radiograph showing multiple small dense nodules in both lungs in silicosis. Note the ‘egg-shell’ calcification of hilar lymph nodes (arrows).
Silicosis
- The small dense nodular opacities represent inhaled silicone particles with local fi brotic reaction.
Discussion
- – Silicosis is an occupational lung disease caused by inhalation of silicone particles
- – There is usually a latent period of ~10-20 years before clinical symptoms occur
Other radiological fi ndings of silicosis not seen in this patient include:
- Progressive massive fi brosis seen as conglomerate masses in both upper lobes due to coalescence of nearby infl ammatory nodules in advanced stage
- Reduction in lung volume due to progressive lung fibrosis
- Apart from diagnosis of silicosis, chest radiograph also helps to detect complications including cor pulmonale, pneumothorax and pulmonary TB
- The differential diagnosis for multiple small pulmonary nodular opacities on CXR include:
- Miliary TB – patient is clinically septic and unwell
- Miliary metastases – background history of underlying malignancy
- Atypical infection (e.g. viral infection)
- Extrinsic allergic alveolitis
Clinical information, particularly relevant occupational history, helps to make the correct diagnosis.
