Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since prior , there has been increased opacification at the left lung base with interval development of a left pleural effusion . The right lung is grossly clear . The cardiomediastinal contour or is normal . There is calcification at the aortic arch . Multiple compression fractures are present , some have mildly progressed from ___ .
    OUTPUT:
    
Left lower lobe opacity , concerning for pneumonia . Adjacent small pleural effusion .