Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-upright radiograph of the chest demonstrates worsening , bilateral , confluent airspace opacities with relative sparing of the extreme lung periphery . Peripheral septal lines are not appreciably changed . The cardiac silhouette is stable in size . A small left pleural effusion and possible right pleural effusion are noted . There is no pneumothorax .
    OUTPUT:
    
Worsening confluent bilateral airspace opacities , which may be due to progressive multifocal pneumonia with or without superimposed secondary process such as noncardiogenic pulmonary edema , aspiration or hemorrhage .