Pulmonary Alveolar Microlithiasis - Clinico-Radiological dissociation - A case report with Radiological review

Area of Science:

• Pulmonary Medicine
• Genetics
• Radiology

Background:

• Pulmonary alveolar microlithiasis (PAM) is a rare chronic lung disease characterized by intra-alveolar calcium and phosphate deposition.
• The exact etiology is unknown, but mutations in the SLC34A2 gene, affecting sodium-phosphate co-transport in alveolar type-II cells, are implicated.
• PAM often presents asymptomatically until the development of hypoxemia and cor pulmonale.

Observation:

• A case of a 44-year-old male with progressive shortness of breath and dry cough is presented.
• Chest radiography revealed a characteristic 'sandstorm' appearance due to dense micronodular opacities.
• High-resolution computed tomography (HRCT) demonstrated microcalcifications, subpleural cystic changes, and pleural calcifications.

Findings:

• Lung biopsy confirmed the presence of calcospherites within alveolar spaces, consistent with PAM.
• The case highlights the typical radiological and pathological findings of pulmonary alveolar microlithiasis.
• The patient's symptoms and diagnostic findings align with the known progression of the disease.

Implications:

• This case report contributes to the understanding of pulmonary alveolar microlithiasis presentation and diagnosis.
• It underscores the importance of genetic factors, specifically SLC34A2 mutations, in the pathogenesis of PAM.
• Further research into the clearance mechanisms of calcium phosphate in the lungs may lead to novel therapeutic strategies.