Diffuse pulmonary nodules

Diffuse pulmonary nodules are usually seen as multiple pulmonary nodular opacifications on a HRCT chest scan. They can signify disease processes affecting either the interstitium or the airspace. They can range from a few millimeters to up to 1 cm and when very small and numerous there can be some overlap with the term miliary nodules. They can arise from a vast number of pathological entities.

Differential diagnosis

Differentials to be considered include:

• sarcoidosis
• silicosis
• respiratory bronchiolitis (infective or non-infective)
• other forms of infection                                      
  • tuberculosis: bronchogenic disseminated tuberculosis
  • non-tuberculous mycobacterial infection
  • other infective bronchiolitides
    • pulmonary haemophilus influenzae infection
    • pulmonary mycoplasma pneumoniae infection
  • fungal infections such as forms of aspergillus infection
  • septic emboli from infective endocarditis or infected tube 
• small airway disease
• hypersensitivity pneumonitis
• malignant entities ​
  • nodular metastases
  • bronchoalveolar carcinoma (now known as AIS-MIA)
  • forms of pulmonary lymphoma
  • kaposi sarcoma
• other miscellaneous conditions​
  • granulomatosis with polyangitis
  • alveolar microlithiasis: very dense
  • diffuse panbronchiolitis
  • diffuse idiopathic pulmonary neuroendocrine cell hyperplasia
  • pulmonary amyloidosis: nodular forms

Related articles

• approach to diffuse pulmonary nodules
• solitary pulmonary nodule