What is sarcoidosis?
Sarcoidosis is an inflammatory
disease that affects multiple organs in the body, but mostly the
lungs and lymph glands. In patients with sarcoidosis, abnormal
masses or nodules (called granulomas) consisting of inflamed
tissues form in certain organs of the body. These granulomas might
alter the normal structure and possibly the function of the
affected organ(s).
Who is at risk for the disease?
Sarcoidosis most often occurs between
20 and 40 years of age, and is diagnosed more often in women than
in men. The disease is 10 to 17 times more common in
African-Americans than in Caucasians. People of Scandinavian,
German, Irish, or Puerto Rican origin are also more prone to the
disease. It is estimated that up to 4 in 10,000 people in the
United States have sarcoidosis.
What causes sarcoidosis?
The exact cause of
sarcoidosis is not known. The disease is associated with an
abnormal immune response, but what triggers this response is
uncertain. How sarcoidosis spreads from one part of the body to
another is still being studied.
What are the symptoms of sarcoidosis?
The symptoms
of sarcoidosis can vary greatly, depending on which organs are
involved. Most patients initially complain of a persistent dry
cough, fatigue, and shortness of breath. Other symptoms and disease
characteristics might include:
- Tender, reddish bumps or patches on the skin
- Red and teary eyes or blurred vision
- Swollen and painful joints
- Enlarged and tender lymph glands in the neck, armpits, and
groin.
- Enlarged lymph glands in the chest and around the lungs
- Nasal stuffiness and hoarse voice
- Pain in the hands, feet, or other bony areas due to the
formation of cysts (an abnormal sac-like growth) in bones
- Kidney stone formation
- Enlarged liver
- Development of abnormal or missed beats (arrhythmias),
inflammation of the covering of the heart (pericarditis), or heart
failure
- Nervous system effects, including hearing loss, meningitis,
seizures, or psychiatric disorders (for example, dementia,
depression, psychosis)
In some people, symptoms might begin suddenly and/or severely,
and subside in a short period of time. Others might have no outward
symptoms at all even though organs are affected. Still others might
have symptoms that appear slowly and subtly, but which last or
recur over a long time span.
How is sarcoidosis diagnosed?
There is no single way
to diagnose sarcoidosis, since all the symptoms and laboratory
results can occur in other diseases. For this reason, your doctor
will carefully review your medical history and examine you to
determine if you have sarcoidosis. The following are the main tools
your doctor will use to diagnose sarcoidosis.
- Chest X-rays look for cloudiness (pulmonary infiltrates)
or swollen lymph glands (lymphadenopathy).
- CT scan provides an even more detailed look at the lungs
and lymph glands than provided by a chest X-ray.
- Pulmonary function (breathing) tests measure how well
the lungs are working.
- Bronchoscopy involves passing a small tube
(bronchoscope) down the trachea (windpipe) and into the bronchial
tubes (airways) of the lungs. The purpose of this test is to
inspect the bronchial tubes and to extract a small tissue sample
(biopsy) to look for granulomas and to obtain material to rule out
infection.