Sarcoidosis is an inflammatory disease that may affect many different parts of the body. Small round spots, called granulomas, form in various organs. The spots slow down normal functioning of those organs.

The cause of sarcoidosis is not known. It seems to be related to malfunctioning of the immune system. The disease may be triggered by an infection or exposure to a toxin in the environment.

Some people may be more susceptible to sarcoidosis due to genetic or environmental factors.