Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear stable . The lung volumes are low . There is no evidence for substantial pleural effusion , although a very small one would be difficult to completely exclude on the left side . Instead , the main finding is opacification of the left lower lobe suggesting pneumonia . There is similar reverse S - shaped curvature to the visualized thoracolumbar spine .
    OUTPUT:
    
Findings suggesting left lower lobe pneumonia .