Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable upright chest radiograph was obtained . The lungs are well expanded . Left basal opacity has progressed and could reflect a focus of aspiration or pneumonia . Additional focal opacities in the lateral right mid lung and medial right lower lung could reflect additional sites of infection or aspiration . Interstitial prominence is greater than on the prior and a component of pulmonary edema superimposed upon existing chronic lung disease is suspected . No pneumothorax is seen with perhaps trace bilateral pleural effusions . Cardiomediastinal contours are unchanged .
    OUTPUT:
    
Likely multifocal pneumonia , either aspiration or infectious , with presumed pulmonary edema superimposed on a background of chronic lung disease .