PULMONARY ALVEOLAR MICROLITHIASIS: CLINICAL AND RADIOPATHOLOGICAL REVIEW.

Pulmonary alveolar microlithiasis (PAM) is a rare and slowly progressive diffuse chronic lung disease characterized by deposition of small calcium phosphate spherules within the alveolar cavity. The etiology of the disease is still unknown and is supposed to be due to defect in the inherited local enzyme that is responsible for calcium deposition. The disease is usually seen from birth up to 40 years of age. Most of the patients are asymptomatic or having very mild symptoms and majority of patients either having normal or restrictive pulmonary function tests. Clinically, the disease course is different; it remains static in few patients or it my progress to pulmonary fibrosis, respiratory failure and cor-pulmonale. Often, diagnosed incidentally during radiography of chest for other reasons. Here, we present a 44-year-old male who presented with moderate shortness of breath and dry cough, which has progressed over years. Clinically, on auscultation late fine inspiratory crepitations heard over interscapular, infrascapular and infraaxillary areas. On chest x-ray and HRCT chest, diffuse, dense, large calcifications noted in bilateral lung fields. Spirometry showed restrictive pattern. Bronchoscopic guided lung biopsy was done, which revealed pulmonary alveolar microlithiais. Treatment with corticosteroids was given and on follow up visits, patient improved symptomatically