Scleroderma: An Overview
What is scleroderma?
Scleroderma is a chronic, although rare, autoimmune disease in which normal tissue is replaced with dense, thick fibrous tissue. Normally, the immune system helps defend the body against disease and infection. In patients with scleroderma, the immune system triggers other cells to produce too much collagen (a protein). This extra collagen is deposited in the skin and organs, which causes hardening and thickening (similar to the scarring process).
Although it most often affects the skin, scleroderma also can affect many other parts of the body including the gastrointestinal tract, lungs, kidneys, heart, blood vessels, muscles and joints. Scleroderma in its most severe forms can be life-threatening.
Forms of scleroderma
There are 2 major forms of scleroderma, localized and systemic. Systemic scleroderma can be broken down into two main types: diffuse and limited.
The more common form of the disease, localized scleroderma, affects only a person's skin, usually in just a few places. It often appears in the form of waxy patches or streaks on the skin, and it is not uncommon for this less severe form to go away or stop progressing without treatment.
As its name implies, this form affects many parts of the body. Not only can it affect the skin, but it also can affect many internal organs, hindering digestive and respiratory functions, and causing kidney failure. Systemic scleroderma can sometimes become serious and life-threatening.
Also known as CREST syndrome, each letter stands for a feature of the disease:
- C alcinosis (abnormal calcium deposits in the skin)
- R aynaud's phenomenon (see the symptoms section)
- E sophageal dysmotility (difficulty swallowing)
- S clerodactyly (skin tightening on the fingers)
- T elangectasias (red spots on the skin)
Patients with limited scleroderma do not experience kidney problems. The skin thickening is restricted to the fingers, hands and forearms, and also sometimes the feet and legs. Digestive involvement is confined mostly to the esophagus. Among later complications, pulmonary hypertension, which can develop in 20% to 30% of cases, can be potentially serious. In pulmonary hypertension, the arteries from the heart to the lungs narrow down and generate high pressure on the right side of the heart, which can ultimately lead to right sided heart failure. Early symptoms of pulmonary hypertension include shortness of breath, chest pain, and fatigue.
How common is scleroderma?
Approximately 250 persons per million American adults are affected by scleroderma. It usually develops between the ages of 35 and 55, although a pediatric form also occurs. Scleroderma is four times more common in women than it is in men.
What causes scleroderma?
The exact cause of scleroderma is unknown. Although rarely, scleroderma can run in families. Most cases do not show any family history of the disease. Scleroderma is not contagious.
What are the symptoms of scleroderma?
In addition to the thickening of skin, the following other symptoms may occur in a person with scleroderma:
- Swelling of the hands and feet
- Red spots on the skin (telangectasias)
- Excessive calcium deposition in the skin (calcinosis)
- Joint contractures (rigidity)
- Tight, mask-like facial skin
- Ulcerations on the fingertips and toes
- Pain and stiffness in the joints
- Persistent cough
- Shortness of breath
- Heartburn (acid reflux)
- Difficulty swallowing
- Digestive and gastrointestinal problems
- Weight loss
- Hair loss
In addition to these symptoms, 2 other conditions—Raynaud's phenomenon and Sjögren's syndrome—also affect patients with scleroderma. Approximately 85% to 95% of scleroderma patients experience Raynaud's phenomenon. However, primary Raynaud's phenomenon is common and often occurs by itself without any underlying connective tissue disorder. Only 10% of patients with Raynaud's phenomenon will develop scleroderma.
Sjögren's syndrome is manifested by dry eyes and mouth. This dryness is due to lack of secretion of tears and saliva as a result of immune damage and destruction of the moisture-producing glands of the body. This condition is named after the Swedish eye doctor, Henrik Sjögren, who first described it. It is seen in approximately 20% of patients with scleroderma.