Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The right PICC line is unchanged in position . The lung volumes are extremely low . There is mild pulmonary vascular congestion . Additionally , there is worsening opacity in the left lung base that may represent pleural effusion vs . atelectasis vs . pneumonia . There is no pneumothorax . No acute osseous abnormalities .
    OUTPUT:
    
Worsening left lung base opacity that is most likely due to pleural effusion and adjacent atelectasis . However , pneumonia can not be excluded in the appropriate clinical setting .