Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is normal . The mediastinal and hilar contours are unchanged , with mild tortuosity of the thoracic aorta . Increased interstitial markings are again noted diffusely bilaterally , which is unchanged when compared to the prior exams and may be chronic or suggestive of mild interstitial pulmonary edema . Small right pleural effusion is noted , with more focal opacity in the right lung base which may represent area of developing infection . No pneumothorax is present . There are degenerative changes in both acromioclavicular joints as well as within the thoracic spine .
    OUTPUT:
    
Continued bilateral diffuse increased interstitial markings , which may reflect chronic changes or mild interstitial pulmonary edema . More focal opacity within the right lung base may represent an area of infection , with a small right pleural effusion .