Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable and frontal chest radiograph demonstrates persistent contrast opacification of the left lower lobe concerning for atelectasis versus pneumonia . The right lung is grossly clear . There is no appreciable pleural effusion . The cardiomediastinal and hilar contours are stable . No pneumothorax . VP shunt is identified in constant position . Enteric tube is seen terminating in the stomach in appropriate position .
    OUTPUT:
    
Retrocardiac left lower lobe opacification concerning for atelectasis vs . pneumonia . These findings were communicated to the house staff caring for the patient upon discovery of these findings .