Sarcoidosis is an autoimmune disease that leads to inflammation that can affect almost any organ in the body, but mostly the lungs, lymph nodes and/or skin are affected. The characteristic feature of sarcoidosis is the formation of granulomas, which are microscopic clumps of cells, in affected tissues. These granulomas can alter the normal structure and impair the function of the affected organ(s).

The cause of sarcoidosis is unknown. It is most likely due to a combination of environmental and genetic factors.

Who is affected?

Sarcoidosis most often occurs between 20 and 40 years of age with women being diagnosed more frequently than men. It is more commonly found in African-Americans and people of Scandinavian, German, Irish or Puerto Rican descent.

Signs & Symptoms

Many people display little or no symptoms and diagnosis is often made by excluding other similar diseases. A third of patients will experience non-specific symptoms of fever, fatigue, weight loss, night sweats and an overall feeling of ill health. Some of the more common signs and symptoms are:

  • Persistent cough
  • Shortness of breath, particularly with exertion and chest pain
  • Enlarged lymph nodes around the lungs
  • Painful or red, raised bumps on the legs or arms (erythema nodosum)
  • Joint pain
  • Blurred vision, eye pain
  • Enlarged or inflamed liver


There is no cure but for some no treatment is required if the signs and symptoms are relatively mild. Sarcoidosis often goes away on its own. If organ function is threatened then medication in the form of immunosuppressants is often prescribed to prevent organ damage. Although sarcoidosis is not often serious, about one-third of people diagnosed with the disease experience permanent organ damage (eg permanent scarring of the lung).

The Centre for Personalised Immunology is investigating the cause of this rare autoimmune disease, to improve treatments and to help to find a cure for this little known autoimmune disorder. Read more on how CPI is helping.

Information on this page is not intended to replace medical advice and any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner.