Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The hilar and mediastinal contours are unremarkable . There is a new vague opacification at the left lung base posteriorly , which may be from an infectious etiology in the correct clinical setting . There is no pneumothorax or pleural effusion . No other focal consolidations are identified . The visualized osseous structures are normal .
    OUTPUT:
    
Probable left lower lung pneumonia in the appropriate clinical setting . These findings were discussed with Dr . ___ by Dr . ___ , by telephone , on the day of the exam at 5 : 15 pm .