Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single frontal portable view of the chest was performed . Again seen is chronic diffuse interstitial reticulation with bronchiectasis as previously described . Increased opacification at the left lung base may represent atelectasis or pneumonia in the correct clinical setting . There is no pleural effusion or pneumothorax . The heart size is normal . There are no suspicious osseous lesions .
    OUTPUT:
    
Opacification of the left lung base may represent atelectasis , however , pneumonia can not be excluded in the right clinical setting .