Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Normal cardiomediastinal contours . Apparent increased density in the right lung and at the left base may reflect differences in image resolution or worsening underlying chronic interstitial lung disease . Pulmonary vascular engorgement reflects mild pulmonary edema superimposed on chronic interstitial lung disease . Possible superimposed viral infection .
    OUTPUT:
    
Mild pulmonary edema superimposed on chronic interstitial lung disease . Possible superimposed infection , likely viral .