Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . There is a small left pleural effusion with associated left basal opacity likely representing atelectasis , difficult to exclude a developing pneumonia . There is mild hilar congestion without frank edema . The cardiomediastinal silhouette is unchanged . Bony structures are intact . Anchors are noted in the left humeral head .
    OUTPUT:
    
Hilar congestion with small left pleural effusion . Left basal opacity likely atelectasis , difficult to exclude a developing pneumonia .