Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiomediastinal contours are a stable . Increasing opacities in the left lower lung are likely infectious in etiology . The upper lungs are clear . There is no pneumothorax or pleural effusion .
    OUTPUT:
    
Increasing ill - defined opacities in the left lower lobe correspond to pneumonia given the provided clinical information