Sarcoidosis is an inflammatory disease that affects multiple organs in the body, but mostly the lungs and lymph glands. In people with sarcoidosis, abnormal masses or nodules (called granulomas) consisting of inflamed tissues form in certain organs of the body. These granulomas may alter the normal structure and possibly the function of the affected organ(s).
The symptoms of sarcoidosis can vary greatly, depending on which organs are involved. Most patients initially complain of a persistent dry cough, fatigue, and shortness of breath. Other symptoms may include:
In some people, symptoms may begin suddenly and/or severely and subside in a short period of time. Others may have no outward symptoms at all even though organs are affected. Still others may have symptoms that appear slowly and subtly, but which last or recur over a long time span.
Who Gets Sarcoidosis?
Sarcoidosis most often occurs between 20 and 40 years of age, with women being diagnosed more frequently than men. The disease is 10 to 17 times more common in African-Americans than in Caucasians. People of Scandinavian, German, Irish, or Puerto Rican origin are also more prone to the disease. It is estimated that up to four in 10,000 people in the U.S. have sarcoidosis.
What Causes Sarcoidosis?
The exact cause of sarcoidosis is not known. It is a type of autoimmune disease associated with an abnormal immune response, but what triggers this response is uncertain. How sarcoidosis spreads from one part of the body to another is still being studied.
How Is Sarcoidosis Diagnosed?
There is no single way to diagnose sarcoidosis, since all the symptoms and laboratory results can occur in other diseases. For this reason, your doctor will carefully review your medical history and examine you to determine if you have sarcoidosis. The main tools your doctor will use to diagnose sarcoidosis include:
Chest X-rays to look for cloudiness (pulmonary infiltrates) or swollen lymph nodes (lymphadenopathy).
CT scan to provide an even more detailed look at the lungs and lymph nodes than provided by a chest X-ray.
Pulmonary function (breathing) tests to measure how well the lungs are working.
Bronchoscopy to inspect the bronchial tubes and to extract a biopsy (a small tissue sample) to look for granulomas and to obtain material to rule out infection. Bronchoscopy involves passing a small tube (bronchoscope) down the trachea (windpipe) and into the bronchial tubes (airways) of the lungs.