Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest are provided . No prior exams for comparison . There is opacity obscuring the left mid and lower lung compatible with pneumonia with an associated pleural effusion . The left lung is essentially clear . No pneumothorax . The heart size can not be assessed due to silhouetting of the right heart border , limiting evaluation . The mediastinal contour appears normal . The bony structures appear intact with degenerative changes at the left shoulder partially imaged .
    OUTPUT:
    
Opacity involving the left mid and lower lung which is concerning for pneumonia with associated effusion . Followup to resolution advised .