Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-upright radiograph of the chest demonstrates a normal cardiomediastinal silhouette and pulmonary vasculature . In the right infrahilar region , new since the prior examination , is an opacity , which in the appropriate clinical context , may represent pneumonia . Vague left basilar opacity is also noted . No large pleural effusion or pneumothorax is identified .
    OUTPUT:
    
Bilateral lower lobe opacities , consistent with pneumonia / possibly aspiration .