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
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.
Sarcoidosis can be difficult to diagnose because the disease produces few signs and symptoms in its early stages. When symptoms do occur, they may mimic those of other disorders.
Your doctor will likely start with a physical exam, including a close examination of any skin lesions you have. He or she will also listen carefully to your heart and lungs and check your lymph nodes for swelling.
Diagnostic tests can help exclude other disorders and determine what body systems may be affected by sarcoidosis. Your doctor may recommend the following tests:
- Chest X-ray to check for lung damage or enlarged lymph nodes
- Computerized tomography (CT scan) if complications are suspected.
- Positron emission tomography (PET) scan or magnetic resonance imaging (MRI) if sarcoidosis seems to be affecting your heart or central nervous system.
- Blood tests to assess your overall health and how well your kidneys and liver are functioning.
- Lung (pulmonary) function tests to measure lung volume and how much oxygen your lungs deliver to your blood.
- Eye exam to check for vision problems that may be caused by sarcoidosis.
Your doctor may order a small sample of tissue (biopsy) be taken from a part of your body believed to be affected by sarcoidosis to look for the granulomas commonly seen with the condition. Biopsies can most easily be taken from your skin if you have skin lesions. Biopsies can also be taken from the lungs and lymph nodes if needed.
There's no cure for sarcoidosis, but in half of cases it goes away on its own. You may not even need treatment if you don't have significant signs and symptoms of the condition, but you should be monitored with regular chest X-rays and exams of the eyes, skin and any other organ involved.
If your symptoms are severe or organ function is threatened, you will likely be treated with medication.
- Corticosteroids. These powerful anti-inflammatory drugs are usually the first-line treatment for sarcoidosis. In some cases, corticosteroids can be applied directly to an affected area — via a cream to a skin lesion or drops to the eyes.
- Medications that suppress the immune system. Medications like methotrexate (Trexall) and azathioprine (Azasan, Imuran) reduce inflammation by suppressing the immune system.
- Hydroxychloroquine. Hydroxychloroquine (Plaquenil) may be helpful for skin disease and elevated blood-calcium levels.
- Tumor necrosis factor-alpha (TNF-alpha) inhibitors. These medications are commonly used to treat the inflammation associated with rheumatoid arthritis. They can also be helpful in treating sarcoidosis that hasn't responded to other treatments.
Organ transplant may be considered if sarcoidosis has severely damaged your lungs, heart or liver.
Because sarcoidosis normally involves the lungs, you may be referred to a lung specialist (pulmonologist) to manage your care.
What you can do
Here's some information to help you get ready for your appointment and know what to expect from your doctor:
- Write down your symptoms, including when they started and how they may have changed or worsened over time.
- Take a list of all your medications, vitamins or supplements.
- Write down your key medical information, including other diagnosed conditions.
- Write down questions to ask your doctor.
What to expect from your doctor
Be ready to answer questions your doctor may ask:
- What types of symptoms are you experiencing? When did they start?
- Have you ever been exposed to environmental toxins, perhaps in a manufacturing or farming job?
- Do you know if anyone in your family has ever had sarcoidosis?
- What types of medical conditions have you had in the past?
- What types of medications or supplements do you take?
Although sarcoidosis usually goes away by itself within two years, some people's lives are forever altered by the disease. If you're having trouble coping, consider talking with a counselor. Participating in a sarcoidosis support group may also be helpful.