Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Diffusely increased interstitial markings likely reflect chronic lung disease . Focal opacity is identified in the left lung base which may reflect atelectasis , however pneumonia is possible in correct clinical setting . There is small left pleural effusion . Cardiac silhouette is moderately enlarged . Heavy calcification is noted in the aorta .
    OUTPUT:
    
Focal opacity is identified in the left lung base which may reflect atelectasis , however pneumonia is possible in correct clinical setting . There is small left pleural effusion .