Pulmonary alveolar microlithiasis in an 8-month-old infant.

Pulmonary alveolar microlithiasis (PAM) in an 8-month-old male infant is reported. He presented initially at 2 months of age with worsening respiratory distress and cyanosis. Chest imaging by X-ray and by CT scan showed widespread reticulo-nodular densities mostly in the mid and lower zones. The diagnosis of PAM was confirmed by an open lung biopsy which showed diffuse alveolar calcium deposits.