Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . The heart remains mildly enlarged . Patient rotation somewhat limits assessment . There is subtle opacity in the left lower lobe which could represent pneumonia . No large effusion or pneumothorax . Right lung is clear . The aorta is unfolded . Bony structures are intact .
    OUTPUT:
    
Subtle opacity in the left lower lobe is concerning for pneumonia .