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Pulmonary Alveolar Microlithiasis "Stone Lungs": A Case of Clinico-Radiological Dissociation
Andrew Chu1, Sameer Shaharyar1, Binna Chokshi1
1Internal Medicine Department GME, Aventura Hospital and Medical Center.
Abstract:
Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by deposition of spherical calcium phosphate microliths called calcospherites within the alveoli. PAM was first described by Friedrich in 1856 and then by Harbitz in 1918. The disease pathogenesis is based on mutations in the SLC34A2 gene that encodes for the Type IIb sodium-phosphate cotransporter. The majority of the patients are diagnosed at an early age, usually between the ages of 20 and 40 years. The hallmark of this disease is a striking dissociation between the radiological findings and the mild clinical symptoms. We report a case of 35-year-old woman who presented post-motor vehicle accident with back pain and with minimal dyspnea on exertion. The final diagnosis was made after computed tomography and lung biopsy. The present case exhibits the remarkable clinico-radiological dissociation with complete calcification of the lungs on radiographic images with a relatively mild clinical presentation.
Insights
Pulmonary alveolar microlithiasis (PAM) is a rare lung disease causing calcium phosphate buildup. This case highlights severe lung calcification with mild symptoms, a common characteristic of PAM.
Area of Science:
- Pulmonary Medicine
- Genetics
- Radiology
Background:
- Pulmonary alveolar microlithiasis (PAM) is a rare infiltrative lung disease characterized by the alveolar deposition of calcium phosphate microliths (calcospherites).
- Pathogenesis is linked to mutations in the SLC34A2 gene, encoding the sodium-phosphate cotransporter.
- PAM typically affects individuals aged 20-40 and presents with a notable discrepancy between imaging results and clinical presentation.
Observation:
- A 35-year-old woman presented with back pain and minimal exertional dyspnea following a motor vehicle accident.
- Radiographic imaging revealed extensive lung calcification.
Findings:
- Computed tomography and lung biopsy confirmed Pulmonary Alveolar Microlithiasis.
- The patient exhibited a striking clinico-radiological dissociation, with complete lung calcification on imaging and mild clinical symptoms.
Implications:
- This case underscores the characteristic dissociation between radiological severity and clinical manifestation in PAM.
- Highlights the importance of considering PAM in patients with unexplained lung opacities, even with minimal symptoms.
- Further research into SLC34A2 gene mutations and their role in PAM pathogenesis is warranted.
