Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Subtle asymmetric increased density at the left lung base without clear lateral correlate may represent infection given correct clinical circumstance . Cardiomediastinal silhouette and hilar contours are unremarkable . There is no pleural effusion or pneumothorax . The osseous structures are grossly unremarkable .
    OUTPUT:
    
Subtle asymmetric increased density at the left lung base without clear lateral correlate may represent infection in the correct clinical circumstance .