Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Severe generalized pulmonary reticulation due to pulmonary fibrosis could obscure either pneumonia or mild pulmonary edema . Heart is mildly enlarged . Pleural effusions are small if any .
    OUTPUT:
    
Severe pulmonary fibrosis . Concurrent pneumonia and pulmonary edema can not be excluded