Systemic Sclerosis
Systemic Sclerosis is a diffuse connective tissue disease
characterized by changes in the skin, blood vessels, skeletal muscles, and internal organs
Causes of Systemic Sclerosis
The cause of Systemic Sclerosis is unknown. The disease may
produce local or systemic
symptoms. The course and severity of the disease varies widely in those affected.
Excess collagen deposits in the skin and other organs produce the symptoms. Damage to
small blood vessels within the skin and affected organs also occurs. In the skin,
ulceration, calcification, and changes in pigmentation may occur.
Systemic features may include fibrosis and degeneration of the heart, lungs, kidneys
and gastrointestinal tract.
The disease usually affects people 30 to 50 years old. Women are affected more often
than men. Risk factors are occupational exposure to silica dust and polyvinyl chloride.
Information about Systemic Sclerosis
Connective tissue is found throughout the body. It is a fibrous tissue produced by
special cells called fibroblasts. Many cells of the immune system exist within the
connective tissue. Connective tissue supports all of the structures of the body, including
the skin, the organs, and all of the body's blood vessels and nerves. Collagen is a type
of protein fiber present in connective tissue.
In Systemic Sclerosis, collagen is over produced and is defective. Collagen then
accumulates throughout the body, causing the hardening (sclerosis), scarring (fibrosis),
and the damage characteristic of Systemic Sclerosis. Because collagen is found so widely
throughout the body, the effects of Systemic Sclerosis are almost always widespread.
Systemic Sclerosis occurs in all races of people all over the world. Patients are most
often diagnosed between the ages of 30-50 years old. Women are three to four times more
likely to suffer from the disorder. Young Afro-American women and Choctaw Native Americans
have particularly high rates of the disease. Although some cases of Systemic Sclerosis
clearly run in families, most cases of Systemic Sclerosis occur without any known family
tendency for the disease.
Causes & symptoms
- blanching, blueness, or redness of fingers and toes in response to heat and cold
(Raynaud's phenomenon)
- pain, stiffness, and swelling of fingers and joints
- skin thickening and shiny hands and forearm
- skin is hard
- tight and mask-like facial skin
- ulcerations on fingertips or toes
- esophageal reflux or heartburn
- difficulty swallowing
- bloating after meals
- weight loss
- diarrhea
- constipation
- shortness of breath
Additional symptoms that may be associated with this disease:
- wrist pain
- wheezing
- skin, abnormally dark or light
- joint pain
- hair loss
- eye burning, itching and discharge
The cause of Systemic Sclerosis remains puzzling. Although the accumulation of collagen
appears to be a hallmark of the disease, doctors do not know why this happens. Some
theories suggest that damage to blood vessels may occur prior to fibrosis. When blood
vessels are damaged, the tissues of the body receive an inadequate amount of oxygen (a
condition called ischemia). Some researchers believe that tissue ischemia and damage then
causes the immune system to over react, creating an autoimmune disorder. The immune system
is designed to produce cells that fight foreign invaders like bacteria, viruses, and
fungi. In this theory of Systemic Sclerosis, the immune system gears up to fight an
invader, but no invader is actually present. Cells of the immune system, called
antibodies, recognize the body's own tissues as foreign. The immune system cells turn
against the already damaged blood vessels and then the vessels' supporting tissues. These
immune cells are designed to deliver potent chemicals in order to kill foreign invaders.
Some of these cells dump these chemicals on the body's own tissues instead, causing
inflammation, swelling, damage, and scarring.
Most cases of Systemic Sclerosis occur with no recognizable initiating event. Some
cases, however, have been traced to poisonous (toxic) exposures. For example, coal miners
and gold miners (both of whom have a lot of exposure to silica dust) have higher than
normal rates of Systemic Sclerosis. Other types of chemicals that have been associated
with Systemic Sclerosis include polyvinyl chloride, benzine, toluene, and epoxy resins. In
1981, 20,000 people in Spain were stricken with a syndrome similar to Systemic Sclerosis
when a toxic substance accidentally contaminated cooking oil. Some claims of a Systemic
Sclerosis-like illness have been made by women with silicone breast implants.
About 95% of all patients with Systemic Sclerosis have a condition called Raynaud's
phenomenon as their first symptom. In Raynaud's disease, the blood vessels of the fingers
and/or toes (the digits) react abnormally to cold. The vessels clamp down, preventing
blood flow to the end of the digit and, eventually, to the entire digit. The affected
digit turns white, then blue, then red when it begins to get blood. Numbness, tingling,
and pain are associated with this entire process. Over time, oxygen deprivation to these
tissues may result in open, irritated pits (ulcers) in the surface of the skin. These
ulcers can lead to tissue death (gangrene) and loss of the digit. These extreme symptoms
of Raynaud's disease rarely occur, except when Raynaud's is associated with other
conditions like Systemic Sclerosis. When Raynaud's disease leads to Systemic Sclerosis,
the next symptoms are usually seen within two years of the first sign of Raynaud's.
Involvement of the skin leads to swelling underneath the skin of the hands, feet, legs,
arms, and face. This is followed by thickening and tightening of the skin, which becomes
taut and shiny. When this tightening is severe, it may cause deformity. For example, skin
tightening on the hands may cause the fingers to become permanently curled (flexed), with
no ability to straighten them. Structures within the skin are damaged (including those
producing hair, oil, and sweat), and skin becomes dry and scaly. Ulcers may form, with the
danger of infection. Calcium deposits often appear under the skin (calcinosis).
As the skin grows tight on the face, the mouth and nose become smaller. The small mouth
may interfere with eating and caring for the teeth. Blood vessels under the skin may
become enlarged and obvious through the skin, appearing as purplish marks
(telangiectasis).
Muscle weakness, joint pain and stiffness, and carpal tunnel syndrome are common.
Carpal tunnel syndrome involves scarring in the wrist, which puts pressure on the median
nerve running through that area. This causes numbness, tingling, and weakness of some of
the fingers.
The tube leading from the mouth to the stomach (the esophagus) becomes stiff and
scarred. Patients may experience difficulty swallowing food. The acidic contents of the
stomach may be allowed to flow backwards into the esophagus (esophageal reflux), causing
severe symptoms of heartburn. Inflammation of the esophagus may occur (esophagitis).
The intestine becomes sluggish in processing food, causing bloating and pain. Foods are
improperly processed, resulting in diarrhea, weight loss, and anemia. Telangiectasis
developing in the stomach or intestine may cause rupture and bleeding.
The lungs are affected in about 66% of all patients with Systemic Sclerosis.
Complications include shortness of breath, coughing, difficulty breathing due to
tightening of the tissue around the chest, inflammation of the air sacs of the lung
(alveolitis), increased chance of pneumonia, and an increased risk of cancer. All of these
have made lung disease the most likely cause of death in Systemic Sclerosis.
The lining around the heart (pericardium) may become inflamed (pericarditis). The heart
may have an increasing amount of difficulty pumping blood effectively (heart failure).
Irregular heart rhythms and enlargement of the heart also occur in Systemic Sclerosis.
Kidney disease is a common complication. Damage to blood vessels of the kidneys is
often responsible for a huge spike in blood pressure, called malignant hypertension. The
blood pressure may be so high that the patient suffers from swelling of the brain, with an
extreme headache, damage to the retinas of the eyes, seizures, and failure of the heart to
pump blood into the body's circulatory system. The kidneys may also stop filtering blood
appropriately, leading to kidney failure. Treatments for high blood pressure and these
kidney complications have greatly improved. Prior to these treatments, kidney problems
were the most common cause of death for patients with Systemic Sclerosis.
Other problems associated with Systemic Sclerosis include painful dryness of the eyes
and mouth, a low functioning thyroid gland (hypothyroidism), difficulty of male patients
to achieve/sustain an erection of the penis, and enlargement and destruction of the liver.
Diagnosis
Diagnosis involves recognizing the relatively unique characteristics of Systemic
Sclerosis symptoms. However, some of these symptoms can accompany other connective tissue
diseases. Some nonspecific laboratory tests that may indicate an inflammatory disorder
(but not specifically Systemic Sclerosis) include:
- Elevated results from a special red blood cell test (erythrocyte sedimentation rate)
- Decreased red blood cell count (anemia)
- Positive tests for certain antibodies (including rheumatoid factor, anti-Scl-70
antibodies, anticentromere antibodies, and antinuclear antibodies).
Other tests can be performed to evaluate the extent of the disease. These can include:
- A test that reveals information about the electrical system of the heart (an
electrocardiogram)
- Lung function tests
- X-ray studies of the gastrointestinal tract
- Various blood tests to study kidney functions.
Treatment
There is no cure for Systemic Sclerosis. A drug called D-penicillamine has been used to
interfere with the defective collagen. It is believed to help decrease the degree of skin
thickening and tightening, and to slow the progress of the disease in other organs.
Steroid medications have been used to interfere with the inflammatory process in Systemic
Sclerosis. Other drugs have been studied that reduce the activity of the immune system
(immunosuppressants), including azathioprine, colchicine, interferon, and 5-fluorouracil.
Because they can have serious side effects, these medications are only used for the most
severe cases of Systemic Sclerosis.
The various complications of Systemic Sclerosis are treated individually. Raynaud's
disease requires that patients try to keep their hands and feet warm constantly, and avoid
situations where they will be exposed to cold temperatures. Thick ointments and creams are
used to treat dry skin. Exercise and massage may help joint involvement, and may help
patients retain more movement despite skin tightening. Skin ulcers will need prompt
attention and may require antibiotics. Patients with esophageal reflux will be advised to
eat small meals more often. They should also avoid foods that may make the reflux worse,
like spicy foods and caffeine-containing items like coffee, tea, and chocolate.
Medications may be given to treat heartburn. Patients must be monitored for the
development of high blood pressure, and promptly and aggressively treated with appropriate
medications. When fluid accumulates due to heart failure, diuretic medications can be
given to help get rid of the excess fluid.
Prognosis
The prognosis for patients with Systemic Sclerosis varies. Some patients, in fact, have
a very limited form of the disease and only their skin is affected. This is called
morphea. These patients have a very good prognosis. Other patients with a cluster of
symptoms called the CREST syndrome also have a relatively good prognosis. CREST stands
for:
- C=Calcinosis
- R=Raynaud's disease
- E=Esophageal dysmotility (stiffness and malfunctioning of the esophagus)
- S=Sclerodactyly (thick, hard, rigid skin over the fingers)
- T=Telangiectasis.
In general, patients with very widespread skin involvement have the worse prognosis.
This level of disease seems to be accompanied by involvement of other organs and the most
severe complications. Although women are more commonly stricken with Systemic Sclerosis,
males more often die of the disease. The most common causes of death include heart,
kidney, and lung diseases. About 65% of all patients survive 10 years or more following a
diagnosis of Systemic Sclerosis.
Prevention
There are no known ways to prevent Systemic Sclerosis. People can try to decrease
exposure to those substances associated with high rates of the disease. These include
silica dust, polyvinyl chloride, benzine, toluene, epoxy resins, and silicone breast
implants.
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