Sarcoidosis is the growth of tiny collections of inflammatory cells (granulomas) in different parts of your body — most commonly the lungs, lymph nodes, eyes and skin.
Doctors believe sarcoidosis results from the body's immune system responding to an unknown substance, most likely something inhaled from the air.
There is no cure for sarcoidosis, but most people do very well with little or only modest treatment. In half of cases, sarcoidosis goes away on its own. In a few cases, however, sarcoidosis may last for years and may cause organ damage.
Signs and symptoms of sarcoidosis vary depending on which organs are affected. Sarcoidosis sometimes develops gradually and produces symptoms that last for years. Other times, symptoms appear suddenly and then disappear just as quickly. Many people with sarcoidosis have no symptoms, so the disease may be discovered only when you have a chest X-ray for another reason.
See your doctor if you have signs and symptoms of sarcoidosis.
For many people, sarcoidosis begins with these symptoms:
- Swollen lymph nodes
- Weight loss
Many patients with sarcoidosis experience lung problems, which may include:
- Persistent dry cough
- Shortness of breath
- Chest pain
Some people who have sarcoidosis develop skin problems, which may include:
- A rash of red or reddish-purple bumps, usually located on the shins or ankles, which may be warm and tender to the touch
- Disfiguring sores (lesions) on the nose, cheeks and ears
- Areas of skin that are darker or lighter in color
- Growths under the skin (nodules), particularly around scars or tattoos
Sarcoidosis can affect the eyes without causing any symptoms, so it's important to have your eyes checked. When eye symptoms do occur, they may include:
- Blurred vision
- Eye pain
- Severe redness
- Sensitivity to light
Signs and symptoms related to cardiac sarcoidosis may include:
- Chest pain
- Shortness of breath (dyspnea)
- Fainting (syncope)
- Irregular heartbeats (arrhythmias)
- Rapid or fluttering heart beat (palpitations)
- Swelling caused by excess fluid (edema)
Doctors don't know the exact cause of sarcoidosis. Some people appear to have a genetic predisposition to develop the disease, which may be triggered by bacteria, viruses, dust or chemicals.
This triggers an overreaction of your immune system and immune cells begin to collect in a pattern of inflammation called granulomas. As granulomas build up in an organ, the function of that organ can be affected.
While anyone can develop sarcoidosis, factors that may increase your risk include:
- Age and sex. Sarcoidosis often occurs between the ages of 20 and 40. Women are slightly more likely to develop the disease.
- Race. African-Americans have a higher incidence of sarcoidosis than do white Americans. Also, sarcoidosis may be more severe and may be more likely to recur and cause lung problems in African-Americans.
- Family history. If someone in your family has had sarcoidosis, you're more likely to develop the disease.
For most people, sarcoidosis resolves on its own with no lasting consequences. But sometimes it causes long-term problems.
- Lungs. Untreated pulmonary sarcoidosis can lead to permanent scarring in your lungs, making it difficult to breathe.
- Eyes. Inflammation can affect almost any part of your eye and can eventually cause blindness. Rarely, sarcoidosis also can cause cataracts and glaucoma.
- Kidneys. Sarcoidosis can affect how your body handles calcium, which can lead to kidney failure.
- Heart. Granulomas in your heart can cause abnormal heart rhythms and other heart problems. In rare instances, this may lead to death.
- Nervous system. A small number of people with sarcoidosis develop problems related to the central nervous system when granulomas form in the brain and spinal cord. Inflammation in the facial nerves, for example, can cause facial paralysis.