Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a consolidation at the left base in the retrocardiac space , most consistent with a left lower lobe pneumonia . The right lung is essentially clear . There is no pulmonary edema , pleural effusion , or pneumothorax . The cardiomediastinal silhouette is normal .
    OUTPUT:
    
Left lower lobe pneumonia .