Sarcoidosis is an inflammatory disease characterized by the development and growth of tiny lumps of cells called granulomas. If these tiny granulomas grow and clump together in an organ, they can affect how the organ works, leading to the symptoms of sarcoidosis. The granulomas can be found in almost any part of the body, but occur more commonly in the lungs, lymph nodes, eyes, skin, and liver. Although no one is sure what causes sarcoidosis, it is thought by most scientists to be a disorder of the immune system responding to an unknown substance, most likely something inhaled from the air. The course of the disease varies from person to person, but most people do very well with little or only modest treatment. It often goes away on its own, but in some people symptoms of sarcoidosis may last a lifetime. For those who need treatment, anti-inflammatory medications and immunosuppressants can help. 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.
For many people, sarcoidosis begins with these symptoms:
- Swollen lymph nodes
- Weight loss
- Skin rashes, ulcers or discoloration
- Joint stiffness or pain
- Enlarged liver or spleen
- Vision problems, eye dryness or irritation
- Headaches, seizures, or weakness on one side of the face
- Aches and pains in the muscles and bones
- Abnormal heart beats
- Kidney stones
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
No one yet knows what causes sarcoidosis. It is thought by most scientists to be a disorder of the immune system, where the body's natural defense system malfunctions 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. Some physicians believe that sarcoidosis may result from a respiratory infection caused by a virus. Others suspect that exposure to toxins or allergens in the environment is to blame. It's also possible that some people have a genetic predisposition to developing sarcoidosis, which, when combined with an environmental trigger, produces the disease. Studies are ongoing to investigate the genetic and environmental components of this disease.
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.
The course of the disease is variable, but most people do well with little or modest treatment. In some people, sarcoidosis can become chronic and lead to complications, including lung scarring, eye disease, skin disease, nervous system problems, heart and liver problems. The mortality rate for sarcoidosis is less than 5%. In the United States, mortality is most commonly due to respiratory failure from pulmonary involvement, cardiac involvement, or neurosarcoidosis. Complications of therapy are additional causes of morbidity and mortality. Prognosis is worse for African Americans, those with advanced pulmonary disease, and those with heart or neurological complications.
The treatment of sarcoidosis depends on
- The symptoms present
- The severity of the symptoms
- Whether any vital organs (e.g., your lungs, eyes, heart, or brain) are affected
- How the organ is affected.
Some organs must be treated, regardless of your symptoms. Others may not need to be treated. Usually, if a patient doesn't have symptoms, he or she doesn't need treatment, and probably will recover in time.
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.
- Mayo Clinic