Discussion: Sarcoidosis is a disorder of unknown etiology characterized by non-necrotizing granulomatous inflammation. Radiographically, the disease is often characterized by bilateral hilar adenopathy, with or without pulmonary or systemic disease. The disease is common among African-Americans. There is a female predominance in the middle-aged years (3:1) . Although the disease can occur at any age, the peak incidence occurs between 20 and 40 years of age. There is an acute form (Lofgren Syndrome) characterized by fever, erythema nodosum, arthralgia of large joints and bilateral hilar adenopathy. Also, there is a chronic form with individuals being asymptomatic 50% of the time or presenting with fever, malaise, weight loss, dry cough and shortness of breath, or hemoptysis (4%). This is a multi-systemic disease which may involve the CNS, eyes, liver/ spleen, GI tract, testes, and heart. 70% have increased ACE titers.
CXR:
Mediastinum / hila:
Adenopathy: *intrathoracic adenopathy (80%)
*"1-2-3" sign or Garland triad---> paratracheal, azygous, and bilateral hilar adenopathy.
*unilateral hilar adenopathy (3-8%)
*mediastinal adenopathy common
Lung disease:
*seen without adenopathy in 16-20% of patients
*reticulonodular 2-3mm (46% of patients)
*acinar 6-7mm nodules (20% of patients)
*alveolar form: multiple large nodules > 10mm +/- air-bronchogram
*progressive fibrosis with upper lobe retraction and bullae (20% of patients)
*end-stage (11% of patients).
HRCT:
*irregular septal thickening *perilymphatic nodules
*traction bronchiectasis *ground-glass opacity
*honeycombing *nodular bronchial wall thickening
Atypical features:
*effusions *solitary nodules
*mycetoma *cavitation
*isolated hilar/mediastinal adenopathy
Staging:
0: (10%) initial normal film
I: (50%) adenopathy only
II: (30%) adenopathy with pulmonary opacities
III:(10%) pulmonary opacities without adenopathy
IV: pulmonary fibrosis, upper lobes with bullae
