Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest show asymmetric opacification at the left base in response to a retrocardiac opacification on the lateral view . In the appropriate clinical setting , this likely represents pneumonia of the left lower lobe . No other areas of focal opacification are noted . Mild right basilar atelectasis is seen . No pleural effusions or pneumothorax is appreciated . The cardiac and mediastinal contours are normal and unchanged since ___ .
    OUTPUT:
    
New asymmetric opacity at the left base concerning for left lower lobe pneumonia .