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Bilateral stony lung: pulmonary alveolar microlithiasis.
Subhash Chandra1, Anant Mohan, Randeep Guleria
1AIIMS, Department of Medicine, Ansari Nagar, New Delhi, Delhi, 110029, India.
BMJ Case Reports
|June 21, 2011
Summary
Pulmonary alveolar microlithiasis (PAM) is a rare lung disease characterized by tiny calcium deposits. This case highlights diagnostic challenges in a paddy field worker mimicking tuberculosis and silicosis.
Area of Science:
- Pulmonary Medicine
- Radiology
- Pathology
Background:
- Pulmonary alveolar microlithiasis (PAM) is an extremely rare lung disease.
- It presents with diffuse bilateral nodular opacities, often challenging to differentiate from other granulomatous lung diseases.
- Occupational exposures can complicate the clinical and radiological presentation.
Purpose of the Study:
- To report a challenging case of pulmonary alveolar microlithiasis (PAM) in a paddy field worker.
- To highlight the diagnostic difficulties in differentiating PAM from silicosis and tuberculosis.
- To emphasize the importance of integrating clinical, radiological, and pathological findings.
Main Methods:
- Case presentation of a 40-year-old male paddy field worker with chronic respiratory symptoms.
- Review of chest radiography, high-resolution computed tomography (HRCT), and pulmonary function tests.
- Confirmation of diagnosis via trans-bronchial lung biopsy.
Main Results:
- Radiological findings included extensive bilateral "sandstorm-like" nodular opacities and "crazy paving" pattern on HRCT.
- Pulmonary function tests showed a restrictive ventilatory defect.
- Histopathology confirmed pulmonary alveolar microlithiasis (PAM) with alveolar calcific bodies.
Conclusions:
- Pulmonary alveolar microlithiasis (PAM) can present insidiously and mimic other lung diseases like tuberculosis and silicosis.
- High-resolution CT findings are crucial for suspecting PAM.
- Definitive diagnosis relies on lung biopsy, underscoring the importance of a multidisciplinary approach.
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