Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unremarkable . The pulmonary vascularity is normal . Patchy ill - defined opacity within the left lower lobe is concerning for pneumonia . The right lung is clear . No pleural effusion or pneumothorax is present . No acute osseous abnormality is present .
    OUTPUT:
    
Left lower lobe pneumonia .