Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size is normal . The mediastinal and hilar contours are unchanged . Pulmonary vasculature is not engorged . Persistent patchy interstitial opacities are noted at the lung bases , not substantially changed in the interval . No pleural effusion or pneumothorax is seen . No acute osseous abnormality is identified .
    OUTPUT:
    
Persistent patchy interstitial opacities in both lung bases concerning for ongoing pneumonia , not substantially changed in the interval .