Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph obtained . Comparison is also made with a prior study from ___ . Extensive bilateral pulmonary opacities persist , which is compatible with known pneumonia . There may be a component of superimposed edema though this is somewhat difficult to assess given the extensive background pneumonia . A right pleural effusion appears somewhat loculated . Cardiomediastinal silhouette is impossible to assess .
    OUTPUT:
    
Extensive bilateral pulmonary opacities compatible with known pneumonia with possible superimposed mild edema .