Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Increased opacity in the left lower lobe with air bronchograms and silhouetting of the descending aorta is consistent with infection . No effusion , edema , or pneumothorax . There is mild left lower lobe atelectasis . The cardiomediastinal silhouette is unchanged . No acute ossoues abnormality .
    OUTPUT:
    
Left lower lobe pneumonia .