Sarcoidosis is a multisystem autoimmune disease characterized by non-caseating granulomas. Lung and lymphatic involvement is seen in 90% of patients. Majority of patient has stable disease or in remission with a minority of patient progressed to lung fibrosis. 

Chest radiograph appearance can be classified according to the Stiltzbach system ¹:

• stage 0: normal
• stage 1: lymphadenopathy
• stage 2: lung involvement
• stage 3: both lung involvement and lymphadenopathy
• stage 4: lung involvement only
• stage 5: lung fibrosis.

Although widely known, this classification may not be a good indicator of disease severity. 

CT findings is variable but most commonly manifested by well-defined nodules in the perilymphatic distribution. CT can also better characterized mediastinal adenopathy. Patient with progressive disease can develop pulmonary fibrosis as late sequelae.