Pulmonary Alveolar Microlithiasis Diagnosed by High-Resolution Computed Tomography, Bronchoalveolar Lavage, and Genetic Testing in a Young Adult

We report the case of a 19-year-old Saudi man who presented with a four-day history of cough, whitish sputum, and shortness of breath.Despite relatively mild symptoms and preserved oxygen saturation, chest imaging showed extensive bilateral pulmonary calcification.High-resolution computed tomography demonstrated diffuse sand-like calcified micronodules, interlobular septal thickening with a crazy-paving pattern, and the black pleura sign.Bronchoalveolar lavage cytology revealed microliths with multinucleated giant cells, while genetic testing identified a pathogenic variant in the SLC34A2 gene, supporting the diagnosis.In this patient, the relatively mild clinical presentation contrasted with the extensive radiological abnormalities.The complementary findings from imaging, bronchoalveolar lavage cytology, and the available genetic result supported the diagnosis without the need for surgical lung biopsy.Following completion of the diagnostic workup, the patient was referred for lung transplantation evaluation, and genetic screening of family members was recommended.