Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The inspiratory lung volumes are decreased from ___ . A retrocardiac opacification is new from the preceding radiograph and may contain air bronchograms , concerning for developing left lower lobe pneumonia . A second new opacity in the medial right lung base does not obscure the right heart border and may represent a focal consolidation of the right middle or lower lobe . No large pleural effusion or pneumothorax is present . The cardiac silhouette is normal in size . The mediastinal and hilar contours are within normal limits and unchanged from the prior study .
    OUTPUT:
    
Bibasilar pneumonic infiltrates , less likely atelectasis .