Pulmonary Hypertension and Polycythemia Secondary to Pulmonary Alveolar Microlithiasis Treated with Sequential Bilateral Lung Transplant: A Case Study and Literature Review.

BACKGROUND Pulmonary alveolar microlithiasis is an autosomal recessive disease in which a mutation in the SLC34A2 gene that codes for a sodium phosphate type IIb transporter protein (expressed in human epithelial tissues and functions in the clearance of phosphate ions) leads to the formation of extensive pulmonary intra-alveolar microliths. The subsequent characteristic clinical features of dyspnea and hypoxia are a manifestation of these microliths. There have been fewer than 1000 cases of pulmonary alveolar microlithiasis reported worldwide, and there have been 19 reported lung-transplanted patients.