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What is sarcoidosis?

What is sarcoidosis?

Sarcoidosis is a rare condition that causes small patches of red and swollen tissue, called granulomas, to develop in the organs of the body. Sarcoidosis affects the lungs in about 9 out of 10 people with the condition (pulmonary sarcoidosis). Other organs such as the skin, eyes, brain, nervous system, liver and heart may also be affected (extrapulmonary sarcoidosis).

It's thought that sarcoidosis is caused by the body's immune system starting to attack its own tissues and organs. This leads to inflammation with patches of swelling and redness (granulomas).

For many people with sarcoidosis, symptoms are not severe and improve in a few months or years without treatment. However, in a few people, symptoms gradually get worse over time and become severe. This is known as chronic sarcoidosis.

If treatment is needed, prednisolone (steroid) tablets are usually used to reduce inflammation. Immunosuppressants are sometimes used if steroids don't work well enough or there are concerns about their side effects. Immunosuppressants may help to improve symptoms because they reduce the activity of the body's immune system.

There is more information on sarcoidosis on NHS Choices.