Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views the chest were provided . Lung volumes are somewhat low . Minimal increased opacity abutting the left heart border could represent a very early pneumonia . Otherwise , lungs appear clear . No congestion or edema . No large effusion or pneumothorax . Cardiomediastinal silhouette is normal . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Very subtle opacity abutting the left heart border which in the correct clinical setting could reflect pneumonia .