Sarcoidosis - Causes - Causes

Your immune system creates inflammation to help defend you against germs and sickness. But in sarcoidosis, inflammation goes off track and the cells in your immune system form lumps, called granulomas, in your body. Over time, inflammation may lead to permanent scarring of organs.

How sarcoidosis can affect the lungs. This illustration shows a close-up view of granulomas and scarring in the lungs, as well as enlarged lymph nodes near the lungs.
How sarcoidosis can affect the lungs. This illustration shows a close-up view of granulomas and scarring in the lungs, as well as enlarged lymph nodes near the lungs.

Studies suggest that triggers to your immune system, including infections without symptoms or coming into contact with substances in the environment, can lead to sarcoidosis in certain people. Some of these people have genes that put them at risk for the disease.