Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval progression of severe bilateral interstitial opacities . Mild cardiomegaly is unchanged . The mediastinal and hilar contours are stable . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Interval progression of severe bilateral interstitial opacities . This could be due to sarcoidosis but superimposed chronic interstitial lung disease related to drug reaction can not be excluded .