Sarcoidosis is a relatively rare autoimmune disease that can affect the skin, lungs, heart, brain and nervous system, eyes, and other organs. Although the disease was first recognized about 100 years ago, little is known about what causes it and there is no cure. As an autoimmune disease, sarcoidosis is similar to diseases like rheumatoid arthritis and lupus in how it behaves and how it is treated.
Depending on the severity, treatment may be needed to control what sarcoidosis does. Sarcoidosis can go dormant on its own or with treatment, and its symptoms often do not recur after the initial onset. In a small percentage of cases, sarcoidosis is chronic, requiring on-going treatment, with possible occurrence in other organ systems. Chronic sarcoidosis is apparently cyclic in its activity level, with flares of symptoms and more dormant periods lasting weeks or months. No markers have been identified as indicating how sarcoidosis is going to behave in any individual or how an individual with sarcoidosis is going to respond to treatment, although a physician experienced with sarcoidosis may be able to make a "good guess" based on his or her experience. Whether he or she is willing to voice that guess is another story entirely!
Despite a century of research, little is known about sarcoidosis. Research has discovered what it is not. Among other things, it is not a cancer or tuberculosis or AIDS-related. It is not caused by pine pollen or other identifiable agents like pollution, airborne or otherwise. It is not progressive or contagious. You did not get it from someone else and you cannot give it to another person. As far as we know, nothing you did specifically caused your sarcoidosis.