Pulmonary Alveolar Microlithiasis.

Pulmonary alveolar microlithiasis (PAM) is a rare autosomal recessive condition that is often asymptomatic despite significant changes in chest imaging. Diagnosis is often made when patients become symptomatic in adulthood. There are still no proven treatments, but earlier diagnosis may allow for evaluation of preventative strategies that could improve outcome. It is an important diagnosis to consider in children who have marked radiographic findings with no or very mild symptoms or physical findings. Diagnosis can be made with imaging alone but may necessitate lung biopsy for definitive diagnosis.