[Pulmonary alveolar microlithiasis--a rare cause of bilateral extensive pulmonary infiltrates]

Pulmonary alveolar microlithiasis is a rare disease, which is characterized by pulmonary deposition of calcium phosphate microliths. The radiographic features can be pathognomonic with a "sandstorm"-like opacification throughout the lungs.

A 29-year-old Moroccan presented for the first time 1988 with atypical chest pain. His history was characterized by nephrocalcinosis and pulmonary disease. Physical examination and laboratory values were unremarkable. Chest X-ray revealed extensive bilateral pulmonary infiltrates with "sandstorm"-like opacifications. Sonography showed medullary nephrocalcinosis. The diagnosis of pulmonary alveolar microlithiasis was confirmed by transbronchial biopsy. Over the next 13 years there was only a moderate expansion of the pulmonary infiltrates and a beginning restrictive pattern, whereas the patient was almost symptom-free.

Pulmonary alveolar microlithiasis is a rare cause of bilateral pulmonary infiltrates and should be considered in the differential diagnosis. In some cases there is also an association with calcifications of extrapulmonary organs.