Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . A severe S - shaped scoliosis is again seen . Retrocardiac opacity is noted raising concern for left lower lobe pneumonia . No large effusion or pneumothorax . No convincing evidence for congestion or edema . Overall cardiomediastinal silhouette appears relatively unchanged .
    OUTPUT:
    
Retrocardiac opacity which could represent left lower lobe pneumonia . Please correlate clinically .