Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac , mediastinal and hilar contours are within normal limits . Pulmonary vasculature is normal . Dense opacification in the left lower lobe is present with a small left pleural effusion , not substantially changed in the interval . Minimal patchy opacity in the right lower lobe may reflect atelectasis . No pneumothorax is demonstrated . Clip is noted in the right upper quadrant of the abdomen . There are no acute osseous abnormalities
    OUTPUT:
    
Persistent small left pleural effusion with adjacent left lower lobe opacity likely atelectasis . Infection is not completely excluded .