Isolated diffuse ground-glass opacification

Isolated diffuse ground-glass opacification/opacity (GGO) has a relatively well-defined differential diagnosis although this remains broad and clinical correlation, like many respiratory diseases, is key to diagnosis.

Differential diagnosis

Miller et al. have described the following differential diagnosis :

• acute alveolar disease
  • pulmonary edema
    • cardiogenic pulmonary edema
    • acute respiratory distress syndrome (ARDS)
  • diffuse alveolar hemorrhage
• infections
  • opportunistic
    • pneumocystis pneumonia (PCP)
    • cytomegalovirus pulmonary infection
    • herpes simplex virus pneumonia
    • respiratory syncytial virus bronchiolitis
  • viral
    • COVID-19
• interstitial lung disease
  • hypersensitivity pneumonitis
  • desquamative interstitial pneumonia (DIP)
  • respiratory bronchiolitis interstitial lung disease (RB-ILD)
  • non-specific interstitial pneumonia (NSIP)
  • acute interstitial pneumonia (AIP)
  • lymphocytic interstitial pneumonia (LIP)
  • sarcoidosis
• miscellaneous
  • drug-induced lung disease
  • pulmonary alveolar proteinosis (PAP)
  • cryptogenic organizing pneumonia (COP)
  • adenocarcinoma-in-situ