Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mildly decreased lung volumes . The patient continues to demonstrate several features of asthma , including peribronchial thickening and increased interstitial markings . However , upon review of numerous prior chest radiographs , there is no evidence of lung hyperexpansion at times when the pulmonary parenchyma appears most pathologic , mass making asthma an unlikely primary diagnosis . Additionally , there is an apparent focal airspace opacity overlying the left lower lobe . There is no pleural effusion or pneumothorax . Chronic , mild cardiomegaly . Slight differences in mediastinal contours are likely secondary to patient rotation .
    OUTPUT:
    
1 . Diffusely increased interstitial markings , waxing and waning over the past several months chest radiographs . Given the lack of lung hyperexpansion , as well as well less likely . The findings may represent a recurrent toxic / allergic inhalation or underlying cardiac disease . 2 . Possible superimposed left lower lobe pneumonia . 3 . Chronic , mild cardiomegaly .