Definition
Sarcoidosis is a pathologic condition which affects multiple organs and is characterized by the presence of noncaseating granulomas.

Pathology

• The characteristic, but not pathognomonic, histologic finding is the noncaseating granuloma.
• Healing of the granuloma results in fibrosis and hyalinization.
• Granulomas often contain Schaumann's bodies and asteroid bodies. Refer to Figures 15-33 and 15-34 in your textbook.
• Although any organ or tissue may be involved with granulomas, the lungs, peri-hilar lymph nodes and mediastinal lymph nodes are very common sites. Pulmonary interstitial fibrosis may occur.
• Involvement of the spleen, liver, bone marrow, skin, eye and salivary glands is relatively common.

Etiology/Pathogenesis
Unknown

Epidemiology
More common in women and African-Americans.

Pathophysiology
Patients commonly present with respiratory abnormalities, constitutional findings (fever, fatigue, weight loss, anorexia, night sweats) or a routine chest x-ray with bilateral hilar adenopathy. Clinical finding may be unique to the organ involved, e.g. skin or eye.