What is Sarcoidosis
Sarcoidosis is an inflammatory disease, an immune system disorder, characterized by small lumps or granulomas in lymph nodes and other organs.
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 your body, although it usually affects some organs more than others. It usually starts in one of two places:
- Lymph nodes, especially the lymph nodes in your chest cavity.
Sarcoidosis also often affects your skin, eyes and liver. Less often it affects your spleen, brain, nerves, heart, tear glands, salivary glands, bones and joints.
Sarcoidosis almost always occurs in more than one organ at a time.
Sarcoidosis has an active and a nonactive phase:
In the active phase, the granulomas form and grow. In this phase, symptoms can develop, and scar tissue can form in the organs where the granulomas occur.
In the nonactive phase, the inflammation goes down, and the granulomas stay the same size or shrink. But the scars may remain and cause symptoms.
The course of the disease varies greatly among people.
In many people, sarcoidosis is mild. The inflammation that causes the granulomas may get better on its own. The granulomas may stop growing or shrink. Symptoms may go away within a few years.
In some people, the inflammation remains but doesn't get worse. You may also have symptoms or flare-ups and need treatment every now and then.
In other people, sarcoidosis slowly gets worse over the years and can cause permanent organ damage. Although treatment can help, sarcoidosis may leave scar tissue in the lungs, skin, eyes, or other organs. The scar tissue can affect how the organs work. Treatment usually does not affect scar tissue.
Changes in sarcoidosis usually occur slowly (e.g., over months). Sarcoidosis does not usually cause sudden illness. However, some symptoms may occur suddenly.
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. 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 are the symptoms of Sarcoidosis
The following is a list of signs and symptoms for Sarcoidosis. Note that Sarcoidosis symptoms usually refers to various symptoms known to a patient, but the phrase Sarcoidosis signs may refer to those signs only noticable by a doctor:
How can Sacroidosis be treated
About 60% to 80% of sarcoidosis cases are self-limiting, meaning that they disappear, at least partially, without intervention, usually within 2 to 3 years. Often the patient does not even know that they have sarcoidosis. About 20% to 30% of sarcoidosis patients suffer some permanent damage, usually to the lungs.
If sarcoidosis does not disappear, it either remains stable or progresses. In about 10% to 20% of cases, sarcoidosis can be quite severe and cause permanent debilitation. In about 5% to 10% of cases, it can even be life threatening.
There may be a correlation between the mode of onset and the course of the disease. If, for example, erythrum nodosum begins suddenly, the painful nodes and other symptoms are usually short-lived and disappear without treatment. If, however, the onset is gradual, it is more likely that the disease will continue to progress to fibrosis, which can be debilitating.
When it remits, spontaneously or as a result of corticosteroid treatment, the granulomas disappear completely or are replaced by scar tissue. The scar tissue, in turn, eventually disappears or leads to fibrosis, causing permanent tissue damage.
It is not clear why, but African Americans tend to develop more severe, chronic sarcoidosis than Caucasians. They also tend to suffer more extensive extrathoracic complications (i.e., symptoms in parts of the body outside of the chest, especially the lymph nodes and skin).
If a patient has unusually high levels of calcium in the blood (hypercalcemia), which is fairly uncommon, it may be advisable to avoid calcium-rich foods. Patients with sarcoidosis are especially sensitive to vitamin D and sunlight, which can aggravate hypercalcemia and hypercalciuria.
Treatment options include:
Nonsteroidal Anti-inflammatory Drugs
Because the cause sarcoidosis is unknown, it is difficult to treat. The symptoms of sarcoidosis result from inflamed granuloma tissue and can be relieved, to some extent, by drugs that stop the swelling – in particular, corticosteroids. The dose and duration of corticosteroid treatment varies considerably from case to case. The most common corticosteroid is prednisone.
Although most physicians and researchers agree that corticosteroids improve symptoms in the short term, long term benefits are not clear. For example, there is no evidence that corticosteroid treatment stops the development of fibrosis in the lungs.
Because of the likelihood that sarcoidosis will disappear spontaneously, with or without corticosteroid treatment, there is some controversy about corticosteroid treatment. Some patients do not tolerate it very well.
When should corticosteroids be prescribed? In each case, the physician must weigh the costs and benefits. Indications for systemic corticosteroid therapy include:
- Certain types of cardiac involvement
- Certain types of neurological involvement
- Disfiguring skin lesions
- Muscle involvement
- Persistent hypercalcaemia and hypercalciuria (to prevent kidney failure)
- Problems with the spleen
- Pulmonary infiltration associated with breathlessness, especially if it worsens
- Severe erythrema nodosum
- Symptoms due to pulmonary fibrosis
- Uveitis (inflammation of the eye)
Generally, corticosteroids are not necessary for stage I sarcoidosis. Patients with stage II sarcoidosis with symptoms or progressive decline in lung function measured by serial pulmonary-function tests are recommended to have therapy. If a patient with sarcoidosis does not receive therapy, they should be followed closely for a decline in lung function. Stage III and IV disease is treated.
Swollen lymph glands do not usually require antiinflammatory treatment because they eventually subside on their own. Mild erythrema nodosum can be treated with nonsteroidal antiinflammatory drugs. Some milder ocular symptoms may be managed with topical steroids.
Therapy with corticosteroids generally consists of approximately 30-40 mg of prednisone daily for 8 to 12 weeks. The prednisone is then gradually tapered to the lowest effective dose over a period of 6 to 12 months.
Corticosteroids have many side effects including the following:
- Adrenal insufficiency
- Aseptic necrosis of the femur
- Cushing's syndrome
- Dermal thinning
- Easy bruising
- Growth suppression
- Mood alterations
- Peptic ulcer disease
- Weight gain
It is important to use preventive therapy for osteoporosis if a patient is on long term cortiocsteroids. Corticosteroids should never be discontinued abruptly because of the adrenal suppressive action; the body will not be able to make steroids and the patient can develop shock.
Nonsteroidal anti-inflammatory drugs
In the case of mild erythrema nodosum, nonsteroidal anti-inflammatory drugs (NSAIDs e.g., ibuprofen) can be effective. Due to potenially severe gastrointestinal and cardiovascular side effects, NSAIDs should only be used as instructed.
Methotrexate may be used in patients intolerant of or who do not respond to steroids. There are no large trials of methotrexate therapy or any alternative drugs in sarcoidosis. At the low dose used for sarcoidosis, methotrexate is a cytotoxic drug that suppresses the immune response. The side effects are nausea, mucositis, and suppressed blood counts. Methotrexate itself can cause lung damage and liver damage after prolonged use, so monitoring liver function is necessary. It is one of the more common substitutes for steroids.
Azathioprine is another commonly used drug in steroid resistant or intolerant cases. The side effects with azathioprine are similar to methotrexate -- nausea, mucositis, and decreased blood counts. Methotrexate and azathioprine can increase the risk for infection.
Cyclophosphamide is a cytotoxic drug that is generally reserved for refractory cases. It, too, can cause nausea, mucositis, and decreased blood counts and increased risk for infection. Cyclophosphamide can cause lung toxicity. A major side effect is hemorrhagic cystitis and long term use can lead to bladder cancer.
Chloroquinine phosphate is an antimalarial drug that works well against lung and skin problems caused by sarcoidosis. Side effects of chloroquinine include eye problems, which need to be carefully avoided. Patients should have their eyes examined by an ophthalmologist every 3 to 6 months. Eye problems do not usually develop if the drug is used for less than a year. In rare cases when corticosteroids are not tolerated by the patient, and the patient is suffering from persistent skin problems, chloroquinine can be tried long term. The NIH's National Heart, Lung, and Blood Institute advises, however, that the effectiveness of chloroquinine has not been proven in clinical trials.