Sarcoidosis is characterized by the development and growth of tiny clumps of inflammatory cells in different areas of your body — most commonly the lungs, lymph nodes, eyes and skin.

Doctors believe sarcoidosis results from an abnormal immune response — most likely to something inhaled from the air — but just what triggers this response isn’t known. The course of sarcoidosis is variable from person to person. Often, it goes away on its own, but in some people signs and symptoms of sarcoidosis may last a lifetime.

If you have minor signs or symptoms of sarcoidosis, you may just need to be monitored until the illness resolves. But if signs or symptoms are bothersome or put vital organs at risk, treatment with prescription anti-inflammatory medications can be helpful.


Signs and symptoms of sarcoidosis tend to vary, depending on which organs are affected and for how long you’ve had the disease. Sometimes sarcoidosis develops gradually and produces signs and symptoms that last for years. Or symptoms may appear suddenly and then disappear just as quickly. Many people with sarcoidosis have no symptoms, so the disease may not be discovered until you have a chest X-ray for another reason. For many people, sarcoidosis begins with the following signs and symptoms:
  • Fatigue, Fever, Swollen lymph nodes, Weight loss
  • Lung symptoms:Persistent dry cough, Shortness of breath, Wheezing, Chest pain


Doctors don’t know the exact cause of sarcoidosis. Some people appear to have a genetic predisposition for developing the disease, which may be triggered by exposure to specific bacteria, viruses, dust or chemicals. Researchers are still trying to pinpoint the genes and trigger substances that may be associated with sarcoidosis.

Normally, your immune system helps protect your body from foreign substances and invading microorganisms, such as bacteria and viruses. But in sarcoidosis, some immune cells clump together to form lumps called granulomas. As granulomas build up in an organ, the function of that organ worsens.

Tests and diagnosis

Sarcoidosis can be difficult to diagnose, partly because the disease produces few signs and symptoms in its early stages. And when symptoms do occur, they vary by organ system affected and can mimic those of other disorders. A variety of diagnostic tests can narrow the possibilities and rule out other conditions.:
  • X-ray:A simple chest X-ray can reveal evidence of lung damage or enlarged lymph nodes in your chest. In fact, some people have been diagnosed with sarcoidosis before they have any symptoms — from the evidence provided by chest X-rays taken for other reasons.
  • CT scan:Computerized tomography (CT) uses a computer to combine a large number of X-rays views taken from many different directions into detailed, cross-sectional images of your internal structures.
  • Biopsies:A biopsy is a small sample of tissue taken from a part of your body believed to be affected by sarcoidosis. The sample can be tested for the types of granulomas that are commonly seen in sarcoidosis. Biopsies can most easily be taken from your skin, from lymph nodes right under the skin, or from the outer membrane of your eye.