Choking on Sand: Diffuse Calcification of the Lungs From Pulmonary Alveolar Microlithiasis

Abstract

Widespread pulmonary calcification is a relatively uncommon finding in patients presenting with dyspnea; differential diagnosis is limited, particularly when accompanied by a diffuse "sandstorm" appearance on plain radiographs. Pulmonary alveolar microlithiasis (PAM) is an extremely rare genetic disease characterized by deposition of calcium phosphate microliths in the alveoli and small airways. CASE PRESENTATION: A 33-year-old female from the Mediterranean region presented for acute on chronic dyspnea. Her 10year history of exertional dyspnea was punctuated by two days of acute, unremitting, exertional and resting dyspnea with associated fever, pleurisy, and anxiety. Initial room air oximetry of 68% increased to 92% on 2L supplemental O2. Exam showed cachexia, tachypnea without accessory muscle usage, and diffuse bronchial breath sounds. Laboratory evaluation revealed polycythemia. Computed tomography showed essentially complete lung opacification with diffuse confluent sand-type calcific opacities with air bronchograms. Extensive inpatient workup for precipitating infectious or rheumatologic etiology of acute decline was largely fruitless, including blood and sputum cultures, atypical respiratory panel, fungal cultures, and autoimmune workup. Quantiferon gold testing was positive. Bronchoalveolar lavage showed scattered calcified concretions. She was discharged on supplemental O2 to follow up with an interstitial lung disease specialist and complete latent tuberculosis treatment. She was unfortunately lost to follow up after return to her home country.