Pulmonary Sarcoidosis

Differential Diagnosis

The following must be ruled out in every case

Infection
- Fungi
  - Stain and culture
  - Usually more associated inflammation
- Tuberculosis
  - Stain and culture
  - Usually caseous necrosis
  - Usually more associated inflammation
- Mycobacteria avium intracellulare
  - Stain and culture
  - Usually non-lymphatic pattern, predominantly peribronchial
Reaction to metals/minerals
- Berylliosis may appear identical to sarcoidosis
  - Must be excluded by history
- Aluminum and talc may appear identical to sarcoidosis
  - Must be excluded by history
Hypersensitivity pneumonitis
- Usually loose granulomas with more inflammation
- Must be excluded by history
Local sarcoid-like reactions
- Seen in tissue adjacent to neoplasms and in draining nodes
- Sarcoidosis typically diffusely involves the lung
Wegener granulomatosis
- Necrosis is suppurative with neutrophils
- Necrosis surrounded by palisaded histiocytes