Ultrasonography and computed tomography findings in pulmonary alveolar microlithiasis

Introduction

Pulmonary alveolar microlithiasis (PAM) is a rare disease characterized by intra-alveolar calcium and phosphate deposition. It primarily affects the lungs, although extrapulmonary calcifications or comorbidities may also be seen. Sporadic cases or patients with autosomal recessive familial inheritance have been reported in the literature. The genetic factor implicated in familial cases is mutation in the SLC34A2 gene [Castellana G et al. Eur. Respir Rev. 2015; 24: 607 – 620]. Patients may be asymptomatic despite diffuse radiological involvement, especially in the early period. The most common respiratory symptoms in symptomatic cases are dyspnea, cough, and hemoptysis [Rea G, et al. J Med Ultrason. 2015; 42: 591 –59 4].