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Sarcoidosis is a disease that causes inflammation of the body’s tissues. Inflammation
is a basic response of the body to injury and usually causes reddened skin,
warmth, swelling, and pain. Inflammation from sarcoidosis is different. In sarcoidosis,
the inflammation produces small lumps (also called nodules or granulomas) in
The inflammation of sarcoidosis can occur in almost any organ and always affects
more than one. Most often, the inflammation starts in either the lungs or the
lymph nodes (small bean-shaped organs of the immune system). Once in a while,
the inflammation occurs suddenly and symptoms appear quickly, but usually it
develops gradually and only later produces symptoms.
Sarcoidosis usually is a mild condition and does not result in lasting harm
to tissues. In most patients, the inflammation that causes the granulomas gets
better with or without treatment and the lumps go away. In others, however,
the lumps do not heal or disappear, and the tissues remain inflamed. If untreated,
these tissues can become scarred. The tissue is then called “fibrotic.” But
even those who need treatment can usually lead a normal life.
The cause of sarcoidosis is not yet known— there may be several. For instance,
an abnormal response from the immune system may be involved. (The immune system
normally attacks and eliminates foreign substances, such as bacteria, that enter
Once thought rare, sarcoidosis is now known to be common and affects persons
worldwide. In fact, sarcoidosis is the most common chronic fibrotic interstitial
lung disorder. (Chronic illnesses are those that last for some time or recur
often; interstitial lung diseases affect the tissue that surrounds the air sacs,
blood vessels, and air passageways.)
This fact sheet gives an overview of sarcoidosis. It tells who gets sarcoidosis,
the disease’s symptoms, diagnosis, and treatment, and reviews some of the studies
underway to learn more about the illness. In addition, it provides references
to articles and support groups to contact for more information. The fact sheet
also has special sections on diagnostic tests, the disease’s effects on various
organs, and commonly asked questions. The fact sheet closes with a glossary.
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Sarcoidosis was first identified more than a century ago. In 1869, Jonathan
Hutchinson, an English doctor, saw a 58-year-old man who had “multiple, raised,
dusty-red patches on his feet, fingers, and arm.” Hutchinson later reported
on more patients with patches or lumps on the skin, eyes, or other organs. These
patients had only one affected organ and only later was the disease known to
involve the whole body. The name “sarcoidosis” was coined by Dr. Caesar Boeck
of Norway, who thought the skin lesions looked like benign (not life-threatening)
sarcomas (tumors). The words “sark” and “oid” come from Greek and refer to the
disease’s flesh-like tumors.
Today, it is known that sarcoidosis can affect almost any part of the body—
lungs, eyes, skin, bones, lymph nodes, spleen, liver, heart, and so on. It also
is now known that sarcoidosis can cause hypercalcemia (in which there is too
much calcium in the blood) and hypercalciuria (in which there is too much calcium
in the urine), both of which can lead to kidney stones.
Knowledge has brought better tests to diagnose the disease and improved treatment.
For example, in the 1970s, the use of a flexible bronchoscopic biopsy was initiated
to help diagnose sarcoidosis in the lungs. In this procedure, doctors take a
sample of lung tissue with a bronchoscope, a long, thin, flexible tube, about
the thickness of a pencil (see Box 1). The bronchoscope also lets a doctor look
inside the lungs and, besides improving diagnosis, has added to scientists’
understanding of how the immune system may be involved in the development of
Treatment too has steadily advanced: Cortisone (a steroid drug) was first used
to treat the disease in 1951. In 1958, an x ray “staging” method that describes
the lung x ray pattern was devised to aid diagnosis and treatment. In 1975,
researchers found that the levels in the blood of a substance called angiotensin
converting enzyme (ACE) could be used as a biochemical marker to help identify
and treat those with sarcoidosis. ACE is made by cells in the granulomas. However,
ACE levels are not always elevated in those with sarcoidosis and a high level
alone does not mean someone has the disease. A high level also does not mean
that treatment must be given. Still, the discovery has handed doctors another
tool to help them make diagnosis and treatment decisions.
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Sarcoidosis occurs worldwide. It affects men and women of all ages and races.
However, it occurs most commonly in adults between the ages of 20 and 40, and
in those of African (especially women), Asian, German, Irish, Puerto Rican,
or Scandinavian origin. In the United States, the disease occurs slightly more
often and more severely among African Americans than whites.
Studies also have shown that the disease is more likely to affect certain organs
in certain populations. For example, sarcoidosis of the heart and eye appears
to be more common in Japan. Painful skin lumps on the legs (erythema nodosum)
occur more often in people from Northern Europe.
Sarcoidosis may occur in families. In the United States, this happens more
often among African Americans than whites.
Environmental factors also may affect the occurrence of sarcoidosis. For example,
sarcoidosis occurs more often in nonsmokers than smokers. Several studies have
noted higher rates of sarcoidosis among health care workers. Other environmental
factors, such as beryllium metal (used in aircraft and weapons manufacture)
and organic dust from birds or hay, may cause sarcoidosis-like reactions in
the lungs. Thus, doctors need to know a person’s history of occupational and
environmental exposure in trying to diagnose sarcoidosis. Infectious agents
have been suspected of causing sarcoidosis, but there is no proof of an infectious
cause. More research is needed to better understand the effect of environmental
factors on a person’s risk of developing sarcoidosis.
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A normal organ is made of an orderly arrangement of cells. Sarcoidosis upsets
this arrangement, eventually causing lumps to form in organs. These lumps get
larger and are called “granulomas” because they look like grains of sugar or
sand. These “grains” are very small and can only be seen with a microscope.
Various other diseases can cause the formation of granulomas. For example,
tuberculosis can cause granulomas. However, in other diseases, the granuloma
forms around a particle, germ, or other foreign substance. In the case of tuberculosis,
for instance, the granuloma forms around the invading organism, which is a mycobacterium.
The immune system causes granulomas to form so that the particles, germs, or
other foreign substances can be isolated or eliminated.
In sarcoidosis, there is no such visible enclosed particle or germ. No cause
for the granuloma can be seen under the microscope. The immune system appears
to be responding to an unknown substance.
When thousands of these microscopic granulomas clump together, they result
in a variety of small and large lumps. These lumps can appear on the lungs,
skin, or other organs, such as the eyes, mouth, salivary glands, liver, spleen,
or lymph nodes in the neck, armpits, and groin. Lymph nodes are small organs
of the body’s immune system.
The lumps can show up as shadows on x rays. If many large groups of granulomas
form, they can affect the organ’s function. This can cause symptoms that need
to be treated.
The disease has active and nonactive stages. In the active stage, the immune
system is fighting the disease and granulomas form or enlarge. In this stage,
symptoms can develop and scar tissue can form. In the nonactive stage, the disease
is easing, and the granulomas are stable, shrinking, or have become scars.
The course of the disease varies: In most persons, the sarcoidosis goes away
over time. In others, the sarcoidosis does not get worse, but the disease remains
and a person can feel well or continue to have symptoms. When treatment is given,
it usually shrinks the granulomas, and they may even disappear. Such treatment
may last for many months. In still other persons, scars can form in the granulomas.
The scars often remain, even with treatment, and symptoms may never go away,
and an affected organ may continue to function poorly.
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Most people with sarcoidosis have no symptoms. Some have only one symptom,
while still others have many. Symptoms typically depend on which organs the
disease affects. General symptoms caused by the disease include weight loss,
fatigue, night sweats, fever, and an overall feeling of ill health.
Most often, the disease will affect the lungs. Thus, the most common symptoms
of the disease are a cough that does not go away and shortness of breath, particularly
with exertion. Symptoms common in sarcoidosis include the following—for more
on each organ and for some not listed below, see Box 2:
- Uneasiness, feeling sick (“malaise“)
- Tiredness, fatigue, weakness
- Loss of appetite or weight
- Sweating at night during sleep
Lymph Node Symptoms
- Enlarged lymph nodes—most often those of the neck, but also may be
those under the chin, in the arm pits, or in the groin
- Skin rash—painful or hot red bumps on the legs or arms, or small brownish
and painless bumps on the arms, legs, and/or back
- Burning, itching, tearing, pain
- Red eye
- Sensitivity to light (photophobia)
- Seeing black spots (called floaters)
- Blurred vision
Lungs and Heart Symptoms
- Shortness of breath
- Chest pain
- Irregular heartbeat (palpitations)
- Joint stiffness, swelling—most commonly of the ankles, feet, and hands
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The symptoms of sarcoidosis are like those of other diseases, some more harmful
and even life-threatening. So it is important to properly diagnose the condition.
Someone who is thought to have the disease should see a doctor who specializes
in sarcoidosis, usually a lung physician (pulmonologist). The specialist will
work with patients and their regular physician to help diagnose the disease
and to develop a schedule of treatment and followup care.
To make a diagnosis, a doctor will ask for a medical history and do a physical
examination. The doctor also may need to take laboratory tests of the blood,
a chest x ray, and breathing tests. Some of the tests and procedures used to
help diagnose sarcoidosis are described in Box 1.
Only a biopsy gives a reliable diagnosis of sarcoidosis. In a biopsy, a sample
of tissue is taken from an affected organ. The biopsy tissue can be taken from
any affected organ. So the simplest and least uncomfortable tissue to biopsy
is usually chosen. For example, if the skin and lungs are affected, the biopsy
will be done on the skin. In many cases, a simple skin or a conjunctival (membrane
lining the eyelid’s inner surface) biopsy is done in a doctor’s office under
local anesthesia, and no hospital stay is needed.
The tissue is examined for the presence of granulomas. As noted, these granulomas
will have no germs or particles within them.
A biopsy may not be needed in every case. For instance, erythema nodosum (painful
red bumps, usually on the legs–see Box 2), may be diagnostic of sarcoidosis
when accompanied by an abnormal chest x ray.
In 1941, a skin test was developed to help diagnose sarcoidosis, but it is
not readily available in the United States. Called the Kveim-Siltzbach test,
it involves injecting a standardized preparation of “sarcoidosis” tissue into
the skin. The test is considered positive if a lump forms at the injection site
and a biopsy of the lump shows granulomas. The result is not always positive,
even if the person has sarcoidosis. It is rarely used in the United States because
the U.S. Food and Drug Administration has not approved a test preparation for
sale. However, some hospitals and clinics may have privately prepared a standardized
|BOX 1: KEY TESTS FOR DIAGNOSIS AND TREATMENT
Various tests and procedures are used to help diagnose sarcoidosis. Some
of these also help monitor the disease during and after treatment. Here
are some of the key tests:
Physical Examination: The doctor will look for symptoms
of the disease, such as red bumps on the skin, swollen lymph nodes, or
redness in the eyes. The doctor also will check for other possible causes
of any symptoms.
Chest X Ray: A chest x ray, which poses little risk
to health, can detect sarcoidosis. About 90 percent of all persons with
sarcoidosis will have an abnormal chest x ray.
X-ray beams cannot pass as easily through granulomatous or scarred tissue
as through normal tissue. The x ray may show granulomas, which appear
as a shadow, or enlarged lymph glands in the chest. Frequently, sarcoidosis
is diagnosed because a chest x ray, taken routinely or for some other
reason, shows an abnormality.
Chest x rays also may be taken to follow the course of the disease. However,
the x rays typically are not done as often for this purpose as are the
pulmonary function tests.
Blood Tests: Blood analyses evaluate the number and
types of blood cells in the body. The tests also measure the blood levels
of various proteins, such as ACE (see page 2), which are known to be involved
in immunological activities, as well as increases in calcium levels. Additionally,
they can show liver, kidney, and bone marrow abnormalities that can occur
Pulmonary Function Tests: Pulmonary function tests are
used to monitor the course of the disease in the lungs. These tests are
safe and easy to do. The results are compared over time.
One pulmonary function test uses a “spirometer,” a device that measures
how much and how fast a person can blow air out of the lungs after taking
a deep breath. This amount will be less than normal if there is significant
inflammation and/or scarring in the lung.
Another test measures lung volume, which indicates how much air the lungs
can hold. In some patients, the lungs may shrink or contract due to sarcoidosis,
and the lung volumes will be smaller than normal.
Other tests check for diffusing capacity, or how well a gas moves into
the bloodstream from the lungs. Sarcoidosis makes it harder for oxygen
to move from the lungs into the bloodstream. In one test, a device called
a pulse oximeter is placed on the finger to give the doctor a rough idea
of the level (or saturation) of oxygen in the patient’s blood. An arterial
blood gas test is a more accurate way to check the level of oxygen in
the bloodstream. Blood from an artery (usually in the wrist) is used because
it has passed through the lungs and taken up oxygen. The blood is then
analyzed for its oxygen and carbon dioxide levels. The better the lungs
are working, the more oxygen there will be in the arterial blood.
Fiberoptic Bronchoscopy: In this procedure, a long,
narrow, flexible tube with a light at the end is inserted into an airway
of the lung. This makes it possible for the doctor to look at the tissue
lining the air passageways of the lungs. It is also possible to use the
bronchoscope to obtain small samples of lung tissue and to obtain lung
washings (that contain lung cells) from various parts of the lungs.
Fiberoptic Bronchoscopy Biopsy: In this procedure, a
sample of lung tissue is removed. The procedure is usually done to make
the diagnosis when pulmonary function tests or chest x rays are abnormal
and characteristic of sarcoidosis. If performed, it is done at the time
of a fiberoptic bronchoscopy. The test is done while the patient is awake
but slightly sedated. The test is usually very safe and done on an outpatient
Bronchoalveolar Lavage: Often, a procedure called a
bronchoalveolar lavage (BAL) is done as part of a fiberoptic bronchoscopy.
BAL involves injecting saline (salt water) into a region of the lung.
The fiberoptic bronchoscope then uses suction to remove the fluid, which
has washed out cells and other materials from the tiny air sacs (alveoli)
of the lung. The pulmonary inflammation associated with sarcoidosis begins
in the lung in these air sacs. The removed sample is then examined for
signs of inflammation that reflect the disease’s active stage.
CT Scan: A computed tomographic (CT) scan is a complicated
kind of x ray that gives a better picture of the lungs than the ordinary
chest x ray. A CT scan may be done to better assess how much of the lung
is affected by sarcoidosis.
CT scans are not done routinely because they expose a person to more
radiation than an ordinary chest x ray and are costly. Instead, they are
done when specific factors call for their need. For example, a CT scan
might be done to diagnose sarcoidosis in the brain, spinal cord, nerves—all
of which are dangerous to biopsy. CT scan of the lungs is important if
the patient is coughing up blood.
MR Scan: Magnetic resonance (also called nuclear magnetic
resonance, NMR scanning, or magnetic resonance imaging, MRI) uses powerful
magnets and radio waves to see inside the body. A computer generates images
of the heart, brain, and other organs. The test is not invasive and has
no known hazards. It can show if features typical of sarcoidosis are present
Thallium and Gallium Scans: These scans are used to
help diagnose sarcoidosis and are often done to see if it is in the heart.
Thallium and gallium are radioactive elements. The doctor injects one
of these into a vein and the element collects at places in the body that
have been affected by sarcoidosis or another inflammatory condition. At
a speci- fied time after the injection, the body is scanned for radioactivity.
An increase in the activity at any site might indicate that inflammatory
activity has developed there. The test gives an idea of which tissues
in the body have been affected by the disease and by how much. Since any
inflammation will cause an uptake of the radioactive element, the test
does not give a definitive diagnosis of sarcoidosis.
Eye Test: All persons diagnosed with sarcoidosis should
have an eye test done by an ophthalmologist (eye doctor). Even if there
are no symptoms of the disease in the eyes, the results of the test can
be used to help monitor the disease. If eye symptoms appear, the test
will be repeated during treatment. It also should be repeated periodically
for those treated for their sarcoidosis with a particular drug called
chloroquine or hydroxycholoroquine (Plaquenil) that can sometimes cause
side effects related to vision. Also, patients receiving corticosteroids
need to be seen by an ophthalmologist to check for signs of cataract development.
For the eye examination, the doctor looks into the eye for abnormalities
and does tests to check for color blindness.
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The treatment of sarcoidosis depends on a person’s symptoms. Often, no treatment
is needed—up to 60 percent of those with sarcoidosis receive no therapy. But,
for some, intense treatment is required, especially if there is critical organ
involvement, such as of the lungs, eyes, heart, or central nervous system.
Here are some key points about the use of treatment:
- Treatment is done to control symptoms or to improve the function
of organs affected by the disease.
- Treatment may or may not affect the long-term outcome of the disease.
One study found that 5-10 years after diagnosis, there was no difference
in recovery between those who had received a short course of treatment and
those who had not.
- Sarcoidosis granulomas result from a response of the immune system. Thus,
most medications used to treat sarcoidosis suppress the immune system.
This can leave a person more likely to get sick from an infection, and this
risk must be considered in making treatment decisions.
Treatment for sarcoidosis involves the use of medications. A wide variety
is available, but most are strong and can cause bad side effects. Different
ones will work better for different persons, and sometimes more than one
is used. Living with the symptoms of the disease must thus be weighed against
the side effects produced by the drugs. Drugs are either taken by mouth
for “systemic” effects throughout the body or are applied locally to an
affected area. Local therapy is the safest way to treat the disease, since
only the affected area is exposed to the drug. Drugs can be applied locally
by drop, inhaler, or cream. Drugs used in this way include corticosteroids.
However, to use drugs locally, the affected area must be easily reached.
For instance, drops and creams help with some eye or skin problems, while
inhalers are used to apply steroids to affected lung tissue, especially
to ease coughing and wheezing. However, it does not appear that an inhaled
drug can relieve such symptoms when the affected lung tissue is deep within
Here is a list of the main drugs used to treat sarcoidosis:
- Prednisone. Prednisone belongs to a group of medicines
called corticosteroids or steroids. It is the most commonly used drug for
sarcoidosis. Sometimes it is used in combination with one of the other drugs
listed in this section. Sometimes other steroids are used.
Prednisone almost always relieves symptoms due to inflammation. If a symptom
does not get better after a couple of months of treatment with prednisone,
then there are two possibilities: either the symptom is not due to sarcoidosis,
or it will not improve because sarcoidosis has already caused scarring.
In the first case, the doctor may look for another cause of the symptom;
in the second case, the symptom will not improve with further prednisone
treatment— the drug may even cause more symptoms due to its side effects.
Prednisone treatment usually lasts for many months, but can go on for many
years. If prednisone treatment is stopped after 3 months, the chance that
symptoms will return is 80 percent. If treatment is stopped after 6 months,
the chance that symptoms will return is 50 percent. But, if treatment is
stopped after 1 year, the chance of a return is only 30 percent and, if
treatment is stopped after 2 years, the chance of a return is only 25 percent.
However, prednisone can have bad side effects. These include weight gain,
diabetes, high blood pressure, mood swings, difficulty sleeping at night,
heartburn, acne, and, when prednisone is taken for long periods, thinning
of the bones (osteoporosis) and skin, cataracts, and occasionally glaucoma.
Side effects usually can be managed by the patient working with his or her
doctor. Also, low doses of prednisone can frequently relieve symptoms without
causing significant side effects.
- Hydroxychloroquine. The brand name of this drug is Plaquenil.
Hydroxychloroquine is used to treat various diseases. It has long been used
for malaria and is given for such other diseases as rheumatoid arthritis
and lupus erythematosis (a disorder that causes inflammation of the skin
and other parts of the body). With sarcoidosis, the drug is effective in
about a third of persons. It is more likely to be effective if sarcoidosis
has affected the skin and if there is a high level of calcium in the blood.
Hydroxychloroquine has few side effects, but it can irritate the stomach
and cause eye problems. Anyone taking the drug should have his or her eyes
examined every 6 months.
- Methotrexate. This drug too has long been used to treat
other diseases. With sarcoidosis, the drug works in 60 to 80 percent of
persons. However, it takes up to 6 months to relieve symptoms. The drug
can have various side effects, including nausea and mouth sores. Methotrexate
also can kill white blood cells, a type of blood cell used by the immune
system to fight off infection. Thus, blood tests must be taken regularly
to check the level of these cells. Rarely (less than 1 percent of the time)
methotrexate causes an allergic reaction in the lungs. But this reaction
goes away when treatment with the drug ends. The most serious possible side
effect with methotrexate is liver damage. If methotrexate must be taken
for more than 2 years, a liver biopsy may be done first to see if the organ
has been damaged or if the drug can continue to be used. The drug also can
harm an unborn baby and should not be taken if a woman is pregnant.
Side effects from methotrexate usually occur when the drug is taken at higher
doses than those needed to treat sarcoidosis. The chance of having a bad
side effect also can often be decreased by taking the vitamin folic acid.
- Azathioprine. The brand name of this drug is Imuran.
It also has long been used to treat various diseases and in organ transplantation.
It works in about 50 percent of those with sarcoidosis. Treatment lasts
for more than 6 months. It can lower the number of white blood cells and
may cause nausea. The biggest concern is that it may increase the risk of
developing cancer after treatment. However, this risk has been found only
in transplant patients–and not in those taking the drug for other diseases.
Azathioprine can harm an unborn baby and should not be taken by a pregnant
- Cyclophosphamide. The brand name of this drug is Cytoxan.
Cyclophosphamide is a very strong drug. It is more likely to lower white
blood cells and cause nausea than either methotrexate or azathioprine. Thus
the level of white blood cells in the blood must be closely monitored during
treatment. The drug also can irritate the bladder. Some of those on the
drug for more than 2 years have developed bladder cancer. Because of these
side effects, the drug is given only to those with severe forms of the disease,
such as neurosarcoidosis. The drug can harm an unborn baby and should not
be taken by a pregnant woman.
- Cyclophosphamide can be given intravenously, which lessens some of its
side effects but does not reduce the risk of cancer.
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Those with sarcoidosis need to have their condition checked during and after
treatment. Those who receive no treatment also need regular checkups, since
symptoms can develop later.
The patient will work with his or her sarcoidosis specialist and regular
physician to develop a schedule of periodic examinations and laboratory
tests. The followup examination usually includes a review of symptoms, a
physical examination, a chest x ray, breathing tests, and laboratory blood
tests. How often these examinations and tests are done depends on the severity
of the symptoms and the organs affected at diagnosis, the therapy used,
and any complications that may develop during treatment.
Routine followup care usually lasts for 2-3 years. Whether the specialist
or primary doctor oversees this care depends on symptoms during the first
year of followup (see the first bullet below). Patients should tell their
doctor about any new symptom that lasts for more than a week. They also
should see the doctor if symptoms appear and do not go away before the next
regularly scheduled followup visit. Changes in sarcoidosis occur slowly—usually
over months. Except for disturbed heart rhythms, sarcoidosis does not cause
sudden illness. If at diagnosis, there are no symptoms, a normal breathing test, and
an abnormal chest x ray, then the following is recommended: A followup
examination should be done every 6-12 months until the illness is stable or
improving. The breathing test may be repeated, depending on a patient’s symptoms
and exercise capacity.
Box 1 gives an overview of followup care. Here are some recommendations
for followup care, based on the condition at diagnosis or the treatment
If new eye symptoms have appeared, then the eye test should be repeated. Eye
symptoms are often severe.
If no new symptoms have developed, and the chest x ray is normal, then the
patient can see his or her regular family physician for future followup care.
- If at diagnosis, there are symptoms and an abnormal chest x ray, but
no treatment is needed, then the following is recommended: A followup
examination should be done in 3-6 months. If the sarcoidosis has worsened
by then–causing symptoms, or another abnormal x-ray and abnormal laboratory
tests–treatment may be needed. If treatment is started, further followup tests
may need to be done more often.
- If after diagnosis, treatment is begun with prednisone, then the following
is recommended: Followup tests will be done to monitor for the side effects
of elevated blood pressure, too much weight gain, diabetes, and arthritis
of one or both hips. If after diagnosis, treatment is begun with hydroxychloroquine,
then the following is recommended: The patient needs to have an eye examination
every 6 months while the drug is being taken.
- If after diagnosis, treatment is begun with methotrexate, then the following
is recommended: Monthly blood tests will be done to avoid anemia (in
which the blood lacks enough red blood cells), low white blood cell and platelet
levels, and inflammation of the liver.
| BOX 2: EFFECTS BY ORGAN
Sarcoidosis is a “multiorgan” disease—it always involves more
than one organ. An organ is affected when granulomas cause an abnormality
that can be found during diagnosis or about which a patient complains.
For example, a biopsy may show that bumps on the skin are made of
granulomas. If no other cause for the granulomas is found and there
is evidence of sarcoidosis in another organ, such as the lungs, the
problem is diagnosed as sarcoidosis. Only one organ biopsy is necessary.
Some organs are affected more often than others. Sarcoidosis occurs
most often in the lungs. It also commonly affects the skin, eyes,
lymph nodes, and liver. Less commonly, it affects the spleen, brain,
nerves, heart, tear glands, salivary glands, and bones and joints.
Rarely, it affects other organs, such as the thyroid gland, breasts,
kidneys, and male and female reproductive organs.
A doctor may not detect sarcoidosis in every organ affected by the
disease. Often, the effects of sarcoidosis in an organ are so mild
that there are no symptoms and the organ continues to function well.
In such cases, identifying the disease in that organ is not necessary
and would not change the treatment given. For more on diagnosis, see
pages 4 and 5.
Here is a rundown of how sarcoidosis affects different organs, starting
with the organ most frequently affected and going to the least affected.
Sarcoidosis most commonly affects the lungs. It may affect the lung
tissue itself and lymph nodes in the chest. Its effects can range
from very mild (without symptoms) to severe. Symptoms caused by the
disease occurring in the lungs include shortness of breath, coughing,
wheezing, and, rarely, chest pain. If chest pain occurs, it often
is felt in the middle of the chest and worsens with deep breathing
The disease is usually seen on an x ray. A staging system is used
to classify chest x rays taken to detect sarcoidosis. Stage 0 is a
normal chest x ray. Stage 1 is a chest x ray with enlarged lymph nodes
but otherwise clear lungs. Stage 2 is characterized by a chest x ray
with enlarged lymph nodes plus infiltrates (shadows) in the lungs.
In Stage 3, the infiltrates are present but the lymph nodes are no
longer seen. In Stage 4, the chest x ray shows scars in the lung tissue.
The x-ray stages do not tell the severity of the disease. However,
in general the higher the stage of the x ray, the worse the person’s
symptoms and lung function (as measured by breathing tests). Persons
with Stage 4 x rays usually have some permanent lung damage. But there
is a lot of individual variation, and persons at Stages 0 through
3 may or may not have symptoms.
When no symptoms appear, treatment usually is not given, and persons
recover with time. With or without treatment, persons with symptoms
often improve, and their x-ray and breathing tests become normal.
All those diagnosed with sarcoidosis should see an eye doctor. The doctor
looks in the eyes and does simple tests. In a third of all those diagnosed
with sarcoidosis, the eyes will be affected by the disease.
The disease can cause eyes to become red and painful, especially
in bright light, and blur vision. Other common symptoms are burning
and itching, discomfort, and, if tear ducts and glands are affected,
dryness. Very rarely, permanent damage results, and blindness may
Sarcoidosis of the eyes almost always responds well to treatment.
Most often, the only treatment needed is eye drops.
Sarcoidosis of the skin can result in rashes or various types of
skin lesions. About 10-35 percent of persons with sarcoidosis develop
skin lesions. Other illnesses also can result in skin lesions, so
a biopsy is frequently done to aid diagnosis.
One type of lesion is called erythema nodosum. It produces painful
bumps that can be warm, tender, and red or painful, purple-to-red,
and slightly raised bumps. The bumps appear on the skin, commonly
on the ankles and shins. The lesions may occur along with fever and
These lesions do not contain granulomas (therefore are not biopsied)
and they may occur in other diseases too. However, the lesions are
usually an early sign of sarcoidosis. Typically, erythema nodosum
lesions go away in weeks to months with or without treatment. Because
of this, treatment does not involve drugs ordinarily given for sarcoidosis.
Persons receive either no drugs or, for those who are very uncomfortable,
aspirin or ibuprofen (an over-the-counter anti-inflammatory medication).
Specific skin lesions are another type of problem, and these show
granulomas when a biopsy is done. These lesions may appear as bumps,
ulcers, or, rarely, flat areas of discolored skin. They occur most
commonly near the nose, eyes, back, arms, legs, and scalp and last
a long time. Typically, they are not painful but sometimes itch.
Another lesion is named lupus pernio. This type causes disfiguring
lesions on the nose. Treatment is frequently needed. Also, the lesions
tend to be chronic and often return after treatment is over.
- Lymph Nodes
The body has lymph nodes (or glands) in various areas, including
the neck, armpits, and groin. The nodes are part of the body’s immune
system. The nodes in these areas may be affected by sarcoidosis and
appear as swollen lumps. Treatment may be given to reduce swelling.
Granulomas often form in the liver. However, the disease rarely causes
significant liver damage. Symptoms of the disease in the liver include
fever, fatigue, itching, and pain in the upper right part of the abdomen
(area of the body under the right ribs). The disease can cause the
liver to enlarge.
Blood tests, a CT scan of the abdomen, or a biopsy may be done to
detect sarcoidosis in the liver. The CT scan will show if the liver
is enlarged and if there is a pattern suggesting granulomas in the
organ. The biopsy is done less often and also shows the formation
of granulomas. Sarcoidosis of the liver almost never causes permanent
damage to the organ and, therefore, is usually not treated unless
it is causing significant symptoms. Followup care includes regular
blood tests to monitor how well the liver is working.
If needed, drug treatment reduces granulomas. Rare cases in which
the disease worsens have been treated successfully by liver transplantation.
- Salivary Glands
These include the two parotid glands, which are below and in front
of the ears. When sarcoidosis affects the parotid glands, it causes
them to swell—making the cheeks look enlarged. Sarcoidosis in the
salivary glands can cause the mouth and throat to be excessively dry.
Treatment can be given to ease symptoms.
- Blood, Urinary Tract, and Kidneys
Sarcoidosis can cause too much calcium in the blood and urine. This
results from an enzyme made by the granulomas. Excess calcium in the
urine can lead to painful kidney stones. A blood test for calcium
should be done. If the calcium level is high, it probably will need
treatment. Sarcoidosis patients with high calcium levels should not
take vitamin and mineral supplements containing calcium or vitamin
- Nervous System
The nervous system includes the brain and all the body’s nerves,
and it may be affected by sarcoidosis. The disease can cause a mass
of granulomas in the brain or meninges, which are the membranes
that cover the brain. The disease also can affect one or more nerves
anywhere in the body. Most often, it affects the nerves of the face.
Symptoms of the
disease in the nervous system vary. If there is a mass in the brain,
symptoms can include headaches, visual problems, and weakness or numbness
of an arm or leg. Coma also can occur, but does so rarely. Sarcoidosis
can also can cause headaches.
When sarcoidosis affects a facial nerve, it can cause one side of
the face to droop. This may be the first symptom that someone has
sarcoidosis. The droop often goes away or improves without therapy.
When sarcoidosis affects the spinal cord, it can cause weakness or
even paralysis of the arms or legs. When multiple nerves in more than
one place are affected, the disease can cause weakness, pain, or a
“stinging needles” sensation in those areas.
Sarcoidosis of the nervous system is often hard to diagnose. To be
sure of the diagnosis, a biopsy may have to be done, but this is hard
to do on the brain, nerves, or spinal cord. For the brain, if symptoms
are typical of sarcoidosis and, especially, if the disease has affected
other organs, a CT or MRI scan will be taken to check for any abnormalities
(see Box 1).
Neurologic sarcoidosis usually needs treatment. Nerve tissue heals
slowly, so treatment lasts a long time and may consist of multiple
drugs at high doses.
Sarcoidosis sometimes affects the heart. This happens most often in
Japanese persons living in Japan. The reason is unknown.
can cause the heart to pump weakly. This results in such symptoms
as shortness of breath, swelling of the legs, wheezing, and coughing.
Sarcoidosis also can affect the heart’s electrical pacing and transmission
system, which tells it when to beat. This can make the heart beat
too fast or very slowly, or skip beats. Symptoms of an electrical-system
problem include palpitations (a fluttering sensation of rapid heartbeats),
skipped beats, and, rarely, fluid buildup in the lungs or sudden loss
Sarcoidosis of the heart is often hard to diagnose. A biopsy can
be taken and a diagnosis made if granulomas are seen. However, granulomas
are often not seen because the tissue sample is small. Thallium or
gallium scans also are used to detect inflammation in the heart (see
Box 1). If a scan shows a particular abnormal pattern, then the diagnosis
of sarcoidosis is made. The diagnosis is more likely if a biopsy has
already proven that the disease exists in another organ.
Sarcoidosis in the heart is usually treated with steroids (see page
6). Additionally, heart drugs are given to improve the heart’s pumping
ability or to correct a disturbed heart rhythm. If a rhythm disturbance
is severe, it may be restored to normal by use of a cardiac pacemaker
(a small battery-operated device, often put under the skin, that regulates
the heartbeat) or defibrillator (an implanted device that shocks a
heart into a normal heartbeat or, if it has stopped, into beating).
If the heart is severely affected and does not respond to therapy,
a transplant may be done. But this is rarely needed.
Sarcoidosis may affect the musculoskeletal system. This includes
the muscles (“musculo”), joints, and bones (“skeletal”).
In muscles—Sarcoidosis of the muscles may cause
severe muscle pain, a mass in the muscle, or muscle weakness.
In joints—Persons with the skin lesions of erythema
nodosum also may develop arthritis in the ankles. This form of arthritis
usually clears up in several weeks. Sarcoidosis also can cause a granulomatous
form of arthritis. Although less common, this condition is chronic
and can last for months or even years. Granulomatous arthritis requires
In bones—Sarcoidosis can cause painless holes in
bones and painless swelling, most commonly in the fingers. Sarcoidosis
also can affect the bone marrow (soft, organic material that fills
bone cavities), which produces blood cells. This can result in anemia,
in which there are too few red blood cells, or a lowered number of
white blood cells. Red blood cells are needed to deliver oxygen to
the body; white blood cells help fight infections. Treatment is usually
given to counter these effects.
Sarcoidosis can affect almost any organ, but rarely strikes the thyroid
gland, the breasts, female and male reproductive systems, or the intestines.
Other areas affected more commonly by the disease include the following:
Sinuses—These are cavities in the skull, and they
can be affected by sarcoidosis and result in frequent bouts of sinusitis
(inflammation of the sinus cavities). Treatment is given to reduce
Spleen—When sarcoidosis affects the spleen, it can
reduce the numbers of red or white blood cells, or platelets (important
in helping blood to clot). The spleen also may enlarge. The person
may feel pain in the upper left part of the abdomen. Treatment is
usually given to increase cell counts and ease pain. Rarely, the spleen
may need to be removed.
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Sarcoidosis affects the body in many ways and the outcome can vary from
person to person. But the chance of recovering from the disease is good.
Most often, the disease goes away within a few years. About 75 percent of
all patients have only the acute form of sarcoidosis and, for about half
of them, the disease leaves no significant problems.
However, sarcoidosis sometimes stays for years and can cause organ damage
and significantly reduce physical activity. About 25 percent of all patients
have the chronic form of the disease. In these patients, the disease usually
leaves scar tissue in the lungs, skin, eyes, or other organ. However, chronic
cases can be improved with treatment.
Sarcoidosis–whether acute or chronic–rarely results in death.
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Scientists in the United States and around the world are trying to learn
more about sarcoidosis and improve its diagnosis and treatment. Much of
this research is being supported by the National Institutes of Health (NIH),
located in Bethesda, MD.
One NIH study is called ACCESS, which stands for “A Case Control Etiologic
Study of Sarcoidosis.” It followed the varied course of the disease in a
large group of persons and resulted in new standards for the diagnosis and
management of sarcoidosis. Other studies now underway are trying to find
the agent or substances that cause sarcoidosis. That knowledge would lead
to much-improved diagnostic tests for the disease, along with treatments
able to target its cause and, perhaps, a prevention.
Research also is aimed at finding out why sarcoidosis appears to behave
differently in different races and why it clusters in some families. For
instance, scientists are comparing sarcoidosis symptoms in African Americans
with those in whites. Other researchers are seeking clues about how genes,
passed from one generation to another, may make some members of a family
more likely than others to develop sarcoidosis.
Still other researchers are examining how sarcoidosis progresses at the
cellular and biochemical levels. They want to know what happens after the
agent or substance causing the disease has invaded the body—how cells behave
and communicate with each other to result in sarcoidosis. Some of these
studies already have led to possible new treatments, which in turn are under
Scientists also are testingnew drug treatments for sarcoidosis. These drugs
include medicines used for other diseases, such as thalidomide, pentoxifylline,
|BOX 3: COMMONLY ASKED QUESTIONS
1. Is sarcoidosis a form of cancer?
Sarcoidosis is not a form of cancer. Also, having sarcoidosis does
not appear to increase a person’s risk of developing cancer. In cancer,
cells multiply out of control and lack order; in sarcoidosis, cells
act as if they are growing around an unseen “invader,” forming granulomas
or lumps. However, persons who have sarcoidosis may be at a slightly
elevated risk for developing some types of cancer–for example, lymphomas,
and liver, lung, and skin cancers. The increased risk may be related
to the chronic inflammation in the organ. The overall risk is similar
to what is seen in other chronic conditions, such as diabetes, inflammatory
bowl disease, and rheumatoid arthritis. Some drugs used to treat sarcoidosis
have been shown to increase the risk of cancer, but only when used
in high doses for other conditions.
2. Is sarcoidosis contagious?
Sarcoidosis is not considered contagious. One person cannot “catch”
it from another person.
3. Is sarcoidosis a genetic disease?
A genetic disease is one passed from parent to child. Sarcoidosis
has not been found to be passed from parents to children. However,
for reasons as yet unknown, it can occur in families. If one family
member has the disease, others may be at an increased risk of developing
it. But that risk is still relatively low.
4. How did I get sarcoidosis?
The cause of sarcoidosis is not known. Thus, it is impossible to
say how anyone got the illness. Once the cause is found, it will lead
to improved ways to diagnose and treat the disease. To help find the
answer, the NIH supports research in the United States and worldwide.
5. Why is it so difficult to make the diagnosis of sarcoidosis?
Since its cause is unknown, sarcoidosis cannot be diagnosed directly.
Instead, it must be diagnosed by a number of factors, including symptoms,
results of a medical examination, laboratory tests, and a biopsy.
The process is like putting together the pieces of a jigsaw puzzle.
The pieces allow the doctor to say, “The diagnosis is sarcoidosis.”
The process gives a correct diagnosis more than 95 percent of the
6. What can I do to avoid sarcoidosis or to make it go away?
Since the cause of sarcoidosis is still a mystery, there is no known
way to prevent the disease. Most experts do not believe that making
environmental or lifestyle changes will affect the course of sarcoidosis.
However, those with sarcoidosis can help protect themselves by staying
healthy: Do not smoke. Keep away from substances, such as dusts and
chemicals, which can harm the lungs. Talk with the doctor about whether
or not to use drugs to help stop the inflammation caused by sarcoidosis.
Most patients will get better without treatment.
7. Can doctors tell if the disease will get worse or go away?
No. But the types and severity of symptoms are clues about how the
disease will progress. For instance, those who have shortness of breath
that grows worse usually develop a chronic and more severe case of
sarcoidosis. Also, those who have sarcoidosis of the skin sometimes
develop a chronic and more severe case of the disease, while those
with erythema nodosum almost always get better.
8. Can I become pregnant and have children?
Severe sarcoidosis can reduce the chance of becoming pregnant, particularly
for older women. Nevertheless, many women have given birth to healthy
babies while being treated for sarcoidosis. In turn, a pregnancy has
little effect on the course of sarcoidosis, and treatment usually
continues without interruption. Occasionally, the disease worsens
in women after delivery of a new baby. Women planning to have a baby
should discuss the matter with their doctor. It is especially important
for women with sarcoidosis to have medical checkups throughout and
9. Does sarcoidosis affect African Americans more than others?
African Americans have a higher risk for sarcoidosis than do other
Americans. However, the illness occurs in every race in the United
States—and throughout the world.
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National Heart, Lung,
and Blood Institute Health Information Center
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