Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Lung volumes are low with bronchovascular crowding likely accounting for subtle opacities in the lower lungs . The possibility of an early pneumonia is difficult to exclude in the correct clinical setting . No large effusion or pneumothorax . Heart and mediastinal contours are normal . Imaged osseous structures are intact .
    OUTPUT:
    
Subtle opacity in the lower lungs likely bronchovascular crowding , though difficult to exclude an early pneumonia .