Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . There is a retrocardiac consolidation with air bronchograms in the left lower lobe , consistent with pneumonia . Elsewhere , the lungs appear clear . There is no pleural effusion or pneumothorax . The bony structures are unremarkable .
    OUTPUT:
    
Fairly extensive focus of pneumonia with air bronchograms in the left lower lobe .