Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There slight increase in interstitial markings bilaterally which may be due to mild interstitial edema . No definite focal consolidation is seen . There is no pleural effusion or pneumothorax . The cardiac and mediastinal silhouettes are stable . Multiple old left - sided rib fractures are seen , new since ___ .
    OUTPUT:
    
Mild interstitial edema .