Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . Patchy left base opacity is seen , which could be due to atelectasis , although underlying infectious process may be present in the appropriate clinical setting . No large pleural effusion is seen . No right base atelectasis . No evidence of pneumothorax . The cardiac and mediastinal silhouettes are similar to prior .
    OUTPUT:
    
Left base opacity worrisome for pneumonia . Recommend followup to resolution .