Pulmonary alveolar microlithiasis: A rare disease treated with lung transplantation, first case from India

Pulmonary alveolar microlithiasis (PAM) is a rare autosomal recessive condition characterized by widespread alveolar deposition of calcium microliths. A mutation in the SLC34A2 gene in the alveolar Type II pneumocytes is responsible for decreased phosphate clearance and accumulation of calcium as spherules in the alveoli. The presence of this gene in other organs is responsible for the systemic phenotype of the disease. PAM is characterized by the lack of defining symptoms such as cough and progressive dyspnea until it reaches the stage of cor pulmonale and presents with features of respiratory and right ventricular (RV) failure. Radiologically, it is characterized by intense calcification in the lung parenchyma producing specific signs such as the "sandstorm appearance" in the early stages to the "white out lung" with "black pleura sign" in the later stages of the disease. While conventional therapy has not been successful at treatment, bilateral lung transplantation offers to be the only effective remedy. In this report, we present the case of a 54-year-old female who presented in the stage of respiratory and RV failure, with oxygen and noninvasive ventilation (NIV) dependence. She was treated with bilateral lung transplantation. Postoperatively, she was monitored closely for immunosuppression, prophylactic anti-infective measures, and bronchoscopies to evaluate for airway complications. The patient gradually improved and was discharged from the hospital without any need for oxygen or NIV.