Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Widespread airspace and interstitial opacities are minimally improved since ___ . There do not appear to be new pleural effusions . There is no pneumothorax . The heart and mediastinum are within normal limits . A rounded calcification in the right upper quadrant likely corresponds to a gallstone . Right shoulder degenerative changes are advanced .
    OUTPUT:
    
Slightly improved widespread airspace and interstitial opacities , which may be due to alveolitis in the setting of drug reaction , noncardiogenic pulmonary edema or infection such as PCP .