Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged . The heart is mildly enlarged . The aortic arch is partly calcified . The lung volumes are again low . There is widespread peripheral coarse reticulation of each lung , most consistent with pulmonary fibrosis , most confluent in the mid to lower than upper lungs . Best seen on the lateral view is a new patchy opacity obscuring the left hemidiaphragm on the lateral view with slight upward tenting . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Patchy left posterior basilar opacity for which pneumonia or atelectasis could be considered , superimposed upon severe background pulmonary fibrosis . Noting comparison with earlier radiographs from ___ , interstitial disease has apparently been worsening .