Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright portable chest radiograph provided . The lung volumes are low , which limits the evaluation . There is subtle opacity at the left lung base , which could represent crowding of bronchovasculature / atelectasis , though an early pneumonia is not excluded . Otherwise , the lungs appear clear . No effusion or pneumothorax . Cardiomediastinal silhouette is unremarkable , though rotation limits evaluation . No bony abnormality .
    OUTPUT:
    
Limited exam with subtle opacity at the left lung base , which could represent pneumonia in the correct clinical setting . If needed , a dedicated PA and lateral view may be obtained to confirm with more optimized technique .