Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Retrocardiac opacity is consistent with left lower lobe pneumonia . Right lung is clear . Cardiomediastinal silhouette is normal . No large effusion or pneumothorax . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
Left lower lobe pneumonia .