Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged including mild - to - moderate unfolding of the descending thoracic aorta . There is new retrocardiac opacity in the left lower lobe , worrisome for pneumonia . The chest is hyperinflated . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Opacity in the left lower lobe suggesting pneumonia .