Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Peribronchial opacity at the base the left lung could be atelectasis or aspiration . If it is pneumonia it is extremely early . There is no pleural effusion , pulmonary edema or pneumothorax . The heart size is normal . The mediastinal contours are normal .
    OUTPUT:
    
Peribronchial abnormality left lower lobe , not clearly pneumonia . Followup advised .