Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest radiographs were obtained . Diffuse ill - defined opacities have become more prominent at both lung bases since the prior examinations . No pneumothorax is present . Mild cardiomegaly is stable .
    OUTPUT:
    
Current radiograph may represent exacerbation of chronic diffuse infiltrative disease such as hypersensitivity pneumonitis or reflect the superimposition of a secondary acute process such as edema or pneumonia on top of chronic changes .