Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: New , moderate right pleural effusion with linear atelectasis at the right base . Superimposed pneumonia can not be excluded . Normal mediastinal and hilar contours . No cardiomegaly . No definite osseous or soft tissue abnormalities .
    OUTPUT:
    
Moderate right pleural effusion . Underlying pneumonia can not be excluded .