• Definition

    Sarcoidosis is a disease in which swelling (inflammation) occurs in the lymph nodes, lungs, liver, eyes, skin, or other tissues.

    Causes, incidence, and risk factors

    The cause of the disease is unknown. In sarcoidosis, clumps of abnnormal tissue (granulomas) form in certain organs of the body. Granulomas are clusters of immune cells.

    The disease can affect almost any organ of the body, but it most commonly affects the lungs.

    Possible causes of sarcoidosis include:

    • Excess sensitivity to environmental factors
    • Genetics
    • Extreme immune response to infection

    The condition is more common in African Americans than Caucasians. Females are usually affected more often than males. The disease typically begins between the ages of 20 and 40. Sarcoidosis is very rare in young children.