Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . Mediastinal contours are unremarkable . Hilar contours are stable , and there is no pulmonary vascular congestion . Left lower lobe opacity is concerning for pneumonia . Right lung is clear . No pleural effusion or pneumothorax is demonstrated . There are no acute osseous abnormalities seen .
    OUTPUT:
    
Left lower lobe opacity concerning for pneumonia . Followup radiographs after treatment are recommended to ensure resolution of this finding .