Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperexpanded , unchanged since priors . The cardiomediastinal silhouette and pulmonary vasculature are stable and unremarkable . There is prominence of the interstitial markings , also unchanged since prior examinations . A new left lower lobe retrocardiac opacity is identified . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Left lower lobe consolidation concerning for pneumonia .