Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Subtle , increased opacity in the left lower lobe with indistinctness of the left hemidiaphragm is more conspicuous compared to the exam in ___ , while could represent a focal pneumonia . The right lung is clear . No pleural effusion or pneumothorax . No edema . Heart size is normal . The descending thoracic aorta slightly tortuous , unchanged .
    OUTPUT:
    
Probable left lower lobe pneumonia .