Pulmonary alveolar microlithiasis

This code represents a rare, chronic lung disease characterized by the accumulation of tiny calcium phosphate stones (microliths) within the alveoli of the lungs. This buildup leads to progressive stiffening of the lungs and impaired gas exchange, often resulting in respiratory insufficiency.

Assign this code when documentation confirms a diagnosis of pulmonary alveolar microlithiasis, typically based on characteristic radiographic findings (e.g., "sandstorm" appearance on chest X-ray) and/or lung biopsy. This diagnosis is often made in patients presenting with chronic cough, dyspnea, and progressive respiratory symptoms.

• Ensure the physician documentation explicitly states "pulmonary alveolar microlithiasis" or a clear synonym.
• Do not confuse this with other interstitial lung diseases or calcifications of different etiologies.
• Code any associated respiratory complications, such as respiratory failure, as secondary diagnoses.