Signs and symptoms of sarcoidosis. Image source: National Heart, Lung, and Blood Institute.
Sarcoidosis involves inflammation that produces tiny lumps of cells in various organs in the body. The lumps are called granulomas because they look like grains of sugar or sand. They are very small and can be seen only with a microscope.
These tiny granulomas can grow and clump together, making many large and small groups of lumps. If many granulomas form in an organ, they can affect how the organ works. This can cause symptoms of sarcoidosis.
Sarcoidosis can occur in almost any part of the body, although it usually affects some organs more than others. It usually starts in one of two places:
Sarcoidosis also often affects the:
Less often, sarcoidosis affects the:
Rarely, sarcoidosis affects other organs, including the:
Sarcoidosis almost always occurs in more than one organ at a time.
Sarcoidosis has an active and a nonactive phase:
The course of the disease varies greatly among people.
Changes in sarcoidosis usually occur slowly (e.g., over months). Sarcoidosis does not usually cause sudden illness. However, some symptoms may occur suddenly. They include:
In some serious cases in which vital organs are affected, sarcoidosis can result in death.
Sarcoidosis is not a form of cancer.
There is no known way to prevent sarcoidosis.
Sarcoidosis was once thought to be an uncommon condition. It's now known to affect tens of thousands of people throughout the United States alone. Because many people who have sarcoidosis have no symptoms, it's hard to know how many people have the condition.
Sarcoidosis was identified in the late 1860s. Since then, scientists have developed better tests to diagnose it and made advances in treating it.
What causes sarcoidosis?
The cause of sarcoidosis is not known. And, there may be more than one thing that causes it.
Scientists think that sarcoidosis develops when the immune system responds to something in the environment (e.g., bacteria, viruses, dust, chemicals) or perhaps to the body's own tissues (autoimmunity).
Normally, the immune system defends the body against things that it sees as foreign and harmful. It does this by sending special cells to the organs that are being affected by these things. These cells release chemicals that produce inflammation around the foreign substance or substances to isolate and destroy them.
In sarcoidosis, this inflammation remains and leads to the development of granulomas or lumps.
Scientists have not yet identified the specific substance or substances that trigger the immune system response in the first place. They also think that sarcoidosis develops only if a person has inherited a certain combination of genes.
A person cannot catch sarcoidosis from someone who has it.
More research is needed to discover what causes sarcoidosis.
Who is at risk for sarcoidosis?
Sarcoidosis affects people of all ages and races worldwide.
It occurs mostly in:
In the United States, sarcoidosis affects African Americans somewhat more often and more severely than Caucasians.
Studies have shown that sarcoidosis is more likely to affect certain organs in certain populations. For example,
People who are more likely to get sarcoidosis include:
Brothers and sisters, parents, and children of people who have sarcoidosis are more likely than others to have sarcoidosis.
What are the signs and symptoms of sarcoidosis?
Many people who have sarcoidosis have no symptoms. Often, the condition is discovered by accident only because a person has a chest X-ray for another reason, such as a pre-employment X-ray.
Some people have very few symptoms, but others have many.
Symptoms usually depend on which organs the disease affects.
Lymph node symptoms
Joint and muscle symptoms
Parotid and other salivary gland symptoms
Blood, urinary tract, and kidney symptoms
Nervous system symptoms
Pituitary gland symptoms (rare)
Sarcoidosis may also cause more general symptoms, including:
These general symptoms are often caused by other conditions. If a person has these general symptoms but doesn't have symptoms from affected organs, he or she probably does not have sarcoidosis.
How is sarcoidosis diagnosed?
Sarcoidosis is diagnosed by taking a detailed medical history and conducting a physical exam and several diagnostic tests. The purpose is to:
A doctor will ask for a detailed medical history. He or she will want to know about any family history of sarcoidosis and what jobs a person has had that may have increased their chances of getting sarcoidosis.
The doctor may also ask whether a person has ever been exposed to inhaled beryllium metal, which is used in aircraft and weapons manufacture, or organic dust from birds or hay. These things can produce granulomas in the lungs that look like the granulomas that are caused by sarcoidosis but are actually signs of other conditions.
A doctor will look for symptoms of sarcoidosis, such as red bumps on the skin; swollen lymph nodes; an enlarged liver, spleen, or salivary gland(s); or redness in the eyes. He or she will also listen for abnormal lung sounds or heart rhythm, and will check for other likely causes of the symptoms.
There is no one specific test for diagnosing sarcoidosis. It is harder to diagnose sarcoidosis in some organs (e.g., heart, nervous system) than in others. A doctor will probably conduct a variety of tests and procedures to help in the diagnosis.
Doctors usually use a staging system for chest X-rays taken to detect sarcoidosis:
Stage 0: Normal chest X-ray
Stage 1: Chest X-ray showing enlarged lymph nodes but otherwise clear lungs
Stage 2: Chest X-ray showing enlarged lymph nodes and shadows in the lungs
Stage 3: Chest X-ray showing shadows in the lungs, but the lymph nodes are not enlarged
Stage 4: Chest X-ray showing scars in the lung tissue.
In general, the higher the stage of the X-ray, the worse the symptoms and lung function are. But there are a lot of differences among people. If the X-ray results show Stages 0, 1, 2, or 3, the patient may not have symptoms or need treatment, and may get better and have normal chest X-rays again over time.
Another test measures how much air the lungs can hold. Sarcoidosis can cause the lungs to shrink, and they will not be able to hold as much air as healthy lungs.
Biopsies of the skin and liver are sometimes done to detect granulomas in these organs.
A person may have sarcoidosis in other organs as well and multiple biopsies may be necessary. However, every organ involved does not need to be biopsied for a diagnosis to be made.
A doctor may do a CT scan to:
Obtain more information about how much of the lung is affected by sarcoidosis.
Detect sarcoidosis in the liver. A CT scan of the abdomen will show if the liver is enlarged and if there is a pattern suggesting granulomas.
This test gives information on the tissue in the body that has been affected by sarcoidosis and the amount of damage to it. But since this test shows all inflammation in the body, even inflammation caused by conditions other than sarcoidosis, it does not give a definite diagnosis of sarcoidosis.
Your doctor may not need to find every one of the organs affected by sarcoidosis, only those that cause symptoms. Often the organs affected by the condition continue to function well and don't need to be treated.
How is sarcoidosis treated?
The goals of treatment are to:
Treatment may shrink the granulomas and even cause them to disappear, but this may take many months. If scars have formed, treatment may not help, and a person may have ongoing symptoms.
A person's treatment depends on:
Some organs must be treated, regardless of the symptoms. Others may not need to be treated. Usually, if a person doesn't have symptoms, he or she doesn't need treatment, and they probably will recover in time.
Prednisone almost always relieves symptoms of inflammation. If a symptom doesn't improve with prednisone treatment within a couple of months, consult your physician.
Prednisone is usually given for many months, sometimes for a year or more.
Low doses of prednisone can often relieve symptoms without causing major side effects.
When used at high doses, prednisone can cause serious side effects.
Side effects can include:
When it is time to stop taking prednisone, a person should cut back slowly, with a doctor's help. This will help prevent flare-ups of sarcoidosis and allow the body to adjust to life without the drug.
A person may also want to see an endocrinologist to make sure that the endocrine glands are making enough hormones. The endocrinologist may prescribe certain hormones for the patient to take until their endocrine glands are working well again.
Other drugs used to treat sarcoidosis
Other drugs are sometimes used to treat sarcoidosis. A doctor may prescribe one of them if:
Most of these other drugs are immune system suppressants. This means that they prevent the immune system from fighting things like bacteria and viruses. As a result, a person may have a greater chance of getting infections.
Most of these drugs also can cause serious side effects. Some also could increase the chances of getting cancer, especially if they are taken at high doses.
A person and his or her doctor must weigh living with the symptoms of sarcoidosis against the side effects of the drugs.
Some drugs work better than others for different people.
A person may be given more than one drug.
Some drugs used to treat sarcoidosis are taken by mouth. Others are applied locally to an affected area.
Local therapy is the safest way to treat sarcoidosis. The drug is applied directly to the affected area. As a result, only small amounts of the drug reach other parts of the body.
Drugs used for local therapy include:
Drugs can be used locally only if the affected area is easily reached. For instance, inhaled steroids can ease coughing and wheezing in the upper airways, but they don't seem to relieve these symptoms when the affected lung tissue is deep within the chest.
A person should talk with their doctor about these treatments and the side effects that may occur.
The other drugs used to treat sarcoidosis include:
A decrease in infection-fighting white blood cells. A person then has a greater chance of getting an infection. If this drug is taken, a person should have regular blood tests to check the levels of their white blood cells.
An allergic reaction in the lungs that goes away when the person stops taking the drug. This is extremely rare.
Liver damage. This is the most serious side effect. If methotrexate is taken, a person should be monitored regularly by a physician.
If a person is pregnant, they should not take this drug. Taking folic acid can help reduce the chances of having bad side effects from methotrexate.
Reduced white blood cell levels, which increases a person's chances of getting an infection.
This drug has caused cancer in some people, especially when they have taken it at high doses. It should not be taken by patients who are pregnant.
Treatments for specific types of sarcoidosis
A cardiac pacemaker, a small battery-operated device, often put under the skin, that regulates the heartbeat
A defibrillator, an implanted device that shocks the heart into a normal heartbeat or, if it has stopped, into beating.
If the heart is severely affected and doesn't respond to treatment, a transplant may be done. But this is rarely needed.
Lupus pernio is often treated by dermatologists, doctors who specialize in skin diseases, working with a sarcoidosis specialist. Because sarcoidosis varies so much among different people, a doctor may find it hard to tell whether the treatment is helping.
Other drugs being studied for possible use in treating sarcoidosis
Scientists also are studying drugs that are used for other conditions to see if they can help people who have sarcoidosis. These drugs include:
What does the future hold?
Scientists worldwide are trying to learn more about sarcoidosis and how to improve its diagnosis and treatment. Some recent studies have led to possible new treatments, which, in turn, are being studied. Current research includes studies of:
Living with sarcoidosis
A person should take steps to stay healthy. This includes:
Joining a patient support group may help adjust to living with sarcoidosis. Talking to others who have the same symptoms can help a person see how they have coped with them.
A patient's regular doctor may be able to diagnose and treat the sarcoidosis, but diagnosis and treatment by a doctor who specializes in sarcoidosis is recommended. If a person prefers to use their regular doctor, they should see a doctor who specializes in the organs that are affected by their sarcoidosis at least once. For example, an ophthalmologist should be seen if the eyes are affected or a pulmonologist if the sarcoidosis is in the lungs. These specialists are often found at major medical centers. They will work with a person's regular doctor to help make a diagnosis, develop a treatment plan, and schedule periodic exams and lab tests.
Many women give birth to healthy babies while being treated for sarcoidosis. Pregnancy usually doesn't affect the course of sarcoidosis, and person can continue corticosteroid treatment through their pregnancy. None of the other drugs are recommended for use during pregnancy.
Sometimes sarcoidosis may get worse after the baby is delivered.
Women with severe sarcoidosis, especially if they are older, may have trouble becoming pregnant.
It's important for a person to discuss this issue with their doctor. A patient who becomes pregnant should be sure to get both good prenatal care and regular sarcoidosis checkups during and after pregnancy.
Regular follow-up care is important, even if a person isn't taking medication for their sarcoidosis. New symptoms can occur at any time, and the condition can get worse slowly, without the person noticing.
Follow-up exams usually include:
The frequency of examinations and tests depends on:
A person will probably need routine followup care for several years. Whether they see their regular doctor or a sarcoidosis specialist for this depends on the symptoms during the first year of follow-up.
Here are some examples of how follow-up care can be managed. They are based on either the person's condition at the time of diagnosis with sarcoidosis or the treatment used.
Follow-up after initial diagnosis
A person should plan on having a follow-up exam every 6 to 12 months until their condition is stable or improving.
A breathing test may need to be repeated. The need to repeat it depends on the symptoms and ability to be active.
They should plan on having a follow-up exam in 3 to 6 months.
If treatment is started, follow-up tests may be needed more often.
Follow-up based on the drug treatment
Checks should be carried out for the side effects of high blood pressure, too much weight gain, diabetes, loss of calcium from the bones, and pain in one or both hips.
An eye exam should be performed every 6 months while taking this drug.
Blood tests should be done every month or every other month to see if there is anemia, low white blood cell or platelet levels, or liver inflammation.
Other follow-up tests
Depending on how serious the condition is and what organs are affected, certain tests may need to be done regularly.
Everyone who is diagnosed with sarcoidosis, even if they don't have eye symptoms, should see an ophthalmologist (eye doctor) for eye tests. This is important because there may be eye damage even if there are no symptoms.
These tests may include:
If eye symptoms develop, a doctor will have you repeat the tests.
A person should also have regular eye exams if they are being treated with:
These tests are used to check the course of sarcoidosis in the lungs. The results are compared over time.
A blood test for calcium should be done. If the calcium level is high, treatment is probably needed. A person also should not take vitamin and mineral supplements containing calcium or vitamin D, and should avoid too much exposure to the sun.
This test is needed to make sure that the heart is still not affected by sarcoidosis. The heart can be affected at any time if the sarcoidosis is active.