Pulmonary Alveolar Microlithiasis: A Rare Case with Characteristic Radiological Findings

Background: Pulmonary alveolar microlithiasis (PAM) is an extremely rare autosomal recessive lung disease characterized by intra-alveolar accumulation of calcium phosphate microliths. The condition demonstrates pathognomonic radiological features with striking clinical-radiological dissociation. Case Presentation: We report a case of PAM discovered incidentally in an asymptomatic patient during routine trauma evaluation following a road traffic accident. Chest radiography revealed the characteristic "sandstorm" appearance with diffuse bilateral micronodular opacities. High-resolution computed tomography (HRCT) demonstrated pathognomonic features including diffuse ground-glass attenuation, calcified interlobular septa creating a "crazy-paving" pattern, subpleural cysts, and bilateral pleural calcifications. The micronodules showed random distribution with lower lobe predominance, particularly in posterior segments of lower lobes and anterior segments of upper lobes. Management and Outcome: The diagnosis was established based on characteristic imaging findings without requiring invasive procedures. The patient remained completely asymptomatic despite extensive bilateral lung involvement, demonstrating the classic clinical-radiological dissociation typical of PAM. Genetic counseling and family screening were recommended given the autosomal recessive inheritance pattern. Conclusion: This case emphasizes the importance of recognizing PAM's pathognomonic radiological features, particularly the sandstorm appearance on chest radiography and crazy-paving pattern on HRCT. Early recognition allows for confident non-invasive diagnosis, appropriate genetic counseling, and long-term monitoring without unnecessary invasive procedures.