Sarcoidosis is a multisystem granulomatous disease of unknown etiology.
This is a worldwide disease with the lowest prevalence in the far east and the highest in Sweden. Sarcoidosis has a higher frequency in people of color and in women, but the disease is also common in whites and men in the U.S. and throughout the world. Sarcoidosis does occur in children and elderly, but most patients present between ages 20-40 years. The most common presenting findings are thoracic lymphadenopathy, lung parenchymal abnormality, and lesions of the skin and eye.