Sarcoidosis is a disease that affects multiple body systems, according to WebMD. The disease is characterized by a buildup of immune cells in organs that form granulomas, which are a small cluster of cells that cause inflammation.
Scientists believe that sarcoidosis is caused by an abnormal immune response, but as of 2015, they are unable to say what exactly triggers the response, states WebMD. Although it can occur within families, there is no hereditary factor in sarcoidosis, nor is the disease contagious. In most cases, people who develop sarcoidosis see the disease appear briefly and then disappear on its own. About 20 to 30 percent people develop some type of permanent lung damage from the disease, and around 10 to 15 percent of people experience chronic sarcoidosis.