Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is normal in size . The mediastinal and hilar contours appear unchanged . There is a mild interstitial abnormality . It may be due to airway inflammation or atypical infection . Mild pulmonary congestion is not excluded . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Mild interstitial abnormality for which airway inflammation or atypical infection could be considered , among other causes .