Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is increased background of vascular congestion ; however allowing this change , there is also increased opacification of the previously aerated left upper lobe concerning for pneumonia with secondary consideration given to increased collapse . There is redemonstration of a dense opacification involving the left mid and lower lungs , likely a combination of atelectasis and effusion . The right border of the cardiomediastinum and hilus are unremarkable .
    OUTPUT:
    
Worsened background of pulmonary vascular congestion . Stable dense left mid and lower lung opacification , a combination of collapse and effusion , with increased opacification in the left upper lobe concerning for pneumonia .