Sarcoidosis

Definition

Sarcoidosis (sahr-koi-DO-sis) is characterized by the development and growth of tiny clumps of inflammatory cells in different areas of your body — most commonly the lungs, lymph nodes, eyes and skin.

Doctors believe sarcoidosis results from an abnormal immune response — most likely to something inhaled from the air — but just what triggers this response isn't known. The course of sarcoidosis is variable from person to person. Often, it goes away on its own, but in some people signs and symptoms of sarcoidosis may last a lifetime.

If you have minor signs or symptoms of sarcoidosis, you may just need to be monitored until the illness resolves. But if signs or symptoms are bothersome or put vital organs at risk, treatment with prescription anti-inflammatory medications can be helpful.

Symptoms

Signs and symptoms of sarcoidosis tend to vary, depending on which organs are affected and for how long you've had the disease. Sometimes sarcoidosis develops gradually and produces signs and symptoms that last for years. Or symptoms may appear suddenly and then disappear just as quickly. Many people with sarcoidosis have no symptoms, so the disease may not be discovered until you have a chest X-ray for another reason.

Generalized symptoms
For many people, sarcoidosis begins with the following signs and symptoms:

• Fatigue
• Fever
• Swollen lymph nodes
• Weight loss

Lung symptoms
Almost everyone who has sarcoidosis eventually experiences lung problems, which may include:

• Persistent dry cough
• Shortness of breath
• Wheezing
• Chest pain

Skin symptoms
Up to 25 percent of the individuals who have sarcoidosis develop skin problems, which may include:

• Rash. A rash of red or reddish-purple bumps, most commonly located on the shins or ankles, may be warm and tender to the touch.
• Lesions. Disfiguring skin sores may occur on your nose, cheeks and ears.
• Color change. Areas of skin may get darker or lighter in color.
• Nodules. Growths just under the skin may develop, particularly around scars or tattoos.

Eye symptoms
Sarcoidosis can affect the eye without causing any symptoms, so it's important to have your eyes checked by a professional. When eye symptoms do occur, they may include:

• Blurred vision
• Eye pain
• Severe redness
• Sensitivity to light

When to see a doctor
Sarcoidosis can cause blindness, so see your doctor promptly if you experience blurred vision, eye pain or extreme sensitivity to light.

Causes

Doctors don't know the exact cause of sarcoidosis. Some people appear to have a genetic predisposition for developing the disease, which may be triggered by exposure to specific bacteria, viruses, dust or chemicals. Researchers are still trying to pinpoint the genes and trigger substances that may be associated with sarcoidosis.

Normally, your immune system helps protect your body from foreign substances and invading microorganisms, such as bacteria and viruses. But in sarcoidosis, some immune cells clump together to form lumps called granulomas. As granulomas build up in an organ, the function of that organ worsens.

Risk factors

While anyone can develop sarcoidosis, factors that may increase your risk include:

• Age and sex. Sarcoidosis usually occurs between the ages of 20 and 40. Women are slightly more likely to develop the disease than are men.
• Race. Black Americans have a higher incidence of sarcoidosis than do white Americans. Also, sarcoidosis may be more severe in blacks and more likely to cause skin problems.
• Ethnicity. Worldwide, sarcoidosis is most commonly reported in people whose families originally came from Northern Europe — particularly Scandinavia and Britain. People with Japanese ancestry are more likely to develop eye or cardiac complications from sarcoidosis.
• Family history. If someone in your family has had sarcoidosis, you are more likely to develop the disease yourself.

Complications

In about two-thirds of people with sarcoidosis, the condition resolves with no lasting consequences. But in some people, sarcoidosis can become chronic and lead to complications that may affect different parts of your body, such as your:

• Lungs. Untreated pulmonary sarcoidosis can lead to irreversible damage to the tissue between the air sacs in your lungs, making it difficult to breathe.
• Eyes. Inflammation can affect almost any part of your eye and can eventually cause blindness. Sarcoidosis can also cause cataracts and glaucoma. However, this is rare.
• Kidneys. Sarcoidosis can affect how your body handles calcium and this can result in kidney failure.
• Heart. Granulomas within your heart can interfere with the electrical signals that drive your heartbeat, which can cause abnormal heart rhythms and even death. This occurs very rarely.
• Nervous system. A small percentage 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 can cause facial paralysis.
• Reproductive system. In men, sarcoidosis can affect the testes and possibly cause infertility. Women with sarcoidosis may find it more difficult to conceive, and their signs and symptoms may worsen after delivery.

Preparing for your appointment

You're likely to start by seeing your family doctor. He or she may eventually refer you to a lung specialist since sarcoidosis most commonly involves the lungs. The pulmonologist might then refer you to other specialists, if needed.

What you can do
Before your appointment, you might want to write a list that answers the following questions:

• 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?

What to expect from your doctor
During the physical exam, your doctor will closely examine any skin lesions you may have, and will listen carefully to your heart and lungs. He or she will also check your lymph nodes for any swelling. Your doctor may also be interested in seeing past chest X-rays, to check for signs of early sarcoidosis that may have been overlooked.

Tests and diagnosis

Sarcoidosis can be difficult to diagnose, partly because the disease produces few signs and symptoms in its early stages. And when symptoms do occur, they vary by organ system affected and can mimic those of other disorders. A variety of diagnostic tests can narrow the possibilities and rule out other conditions.

Imaging tests

• X-ray. A simple chest X-ray can reveal evidence of lung damage or enlarged lymph nodes in your chest. In fact, some people have been diagnosed with sarcoidosis before they have any symptoms — from the evidence provided by chest X-rays taken for other reasons.
• CT scan. Computerized tomography (CT) uses a computer to combine a large number of X-rays views taken from many different directions into detailed, cross-sectional images of your internal structures.

Lab tests
Samples of your blood may be tested to check your general health and to see how well your kidneys and liver are functioning.

Lung function tests
These tests typically measure:

• The volume of your lungs
• How much air you can breathe in and out
• How fast you can breathe air out
• How well your lungs deliver oxygen to your blood

Biopsies
A biopsy is a small sample of tissue taken from a part of your body believed to be affected by sarcoidosis. The sample can be tested for the types of granulomas that are commonly seen in sarcoidosis. Biopsies can most easily be taken from your skin, from lymph nodes right under the skin, or from the outer membrane of your eye.

Lung biopsies can be obtained during a bronchoscopy (brong-KOS-kuh-pee). This procedure uses a thin, flexible tube that contains a fiber-optic camera and a grasping tool. After the tube is inserted down your throat, a doctor uses the grasping tool to remove a small sample of lung tissue — about the size of a grain of rice. The sample is sent to a microbiology laboratory to look for specific organisms.

Treatments and drugs

You may not need treatment if you don't have any signs and symptoms of sarcoidosis or if they aren't bothering you. Sarcoidosis goes away on its own in many cases, but you should undergo close surveillance with regular chest X-rays and exams of the eyes, skin and any other organ involved. Treatment becomes necessary if organ function is threatened.

Medications

• Corticosteroids. Prednisone and other corticosteroids are the first-line treatment for sarcoidosis. In some cases, these powerful anti-inflammatory drugs can be applied directly to an affected area — via a cream to a skin lesion or with an inhaler to your lungs. Oral corticosteroids affect your whole body and can cause weight gain, mood swings, insomnia and weakened bones (osteoporosis).
• Anti-rejection drugs. Drugs such as methotrexate (Trexall) or azathioprine (Imuran) reduce inflammation by suppressing your immune system. But these drugs carry their own risks, such as making you more vulnerable to infections.
• Anti-malarial drugs. Hydroxychloroquine (Plaquenil) may be helpful for skin disease, nervous system involvement and elevated blood-calcium levels. Anti-malarial drugs can harm your eyes, so regular eye exams should be scheduled
• TNF-alpha inhibitors. Tumor necrosis factor-alpha (TNF-alpha) inhibitors are most commonly used to treat the inflammation associated with rheumatoid arthritis. Some studies have indicated that infliximab (Remicade) is also helpful in treating sarcoidosis. Potential side effects include congestive heart failure, blood disorders and lymphoma.

Surgery
Organ transplant may be considered if sarcoidosis has severely damaged your lungs or liver.

Coping and support

There's no cure for sarcoidosis. Treatments simply help manage the symptoms. And while 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, you might want to consider talking with a counselor about your problems. Participating in a sarcoidosis support group may also be helpful.