Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest views were obtained with the patient in upright position . Analysis is performed in direct comparison with the next preceding PA and lateral chest examination of ___ . Previously described heart size , mediastinal structures , and permanent pacer with dual electrode system remain unchanged . The same holds also with the previously described loculated pleural effusion that blunts the left - sided lateral pleural sinus . Parenchymal densities in the posterior portion of the left lower lobe remain unchanged as they present on the lateral view . The only significant difference is the appearance of substantial amount of subdiaphragmatic air which was not found on the preceding chest examination . Telephone contact with referring physician , ___ . ___ , explained this finding as the patient is daily abdominal dialysis .
    OUTPUT:
    
Stable chest findings . Persistent loculated pleural density on the left base and parenchymal density occupying posterior portions of the left lower lobe .