<prompt> Sandstorm appearance on Chest radiograph is characteristic of?Pulmonary edemaPulmonary alveolar proteinosisPulmonary alveolar microlithiasisPulmonary thromboembolism  <response>: Pulmonary alveolar microlithiasis is a chronic disease characterized by widespread diffuse bilateral intraalveolar accumulation of minute calculi microlithiasis especially in mid and lower zones, giving characteristic sandstrom appearance on chest radiographs. 