Systemic scleroderma, also known as systemic sclerosis or SSc, affects connective tissue in many parts of the body. 

The term “systemic sclerosis” indicates that sclerosis (hardening) may occur in the internal systems of the body. Affected body parts may include the skin, lungs, heart, kidney esophagus, gastrointestinal tract (stomach and bowels), and other internal organs. SSc can also affect blood vessels, muscles, and joints. Affected tissues become hard and fibrous, resulting in less efficient function.

Systemic scleroderma may be limited or diffuse.

The extent of skin involvement determines whether a patient has limited cutaneous SSc or diffuse cutaneous SSc. In lcSSc, skin thickening occurs on the hands, forearms, lower legs, and feet. In dcSSc, skin thickening occurs on the hands, forearms, upper arms, thighs, or trunk. Both forms can affect the skin on the face.

Limited cutaneous systemic sclerosis can be slower.

In addition to less widespread skin thickening, internal problems are less frequent and tend to be less severe than in dcSSc. Onset of internal problems is usually delayed for several years. However, the disease can still be extremely severe. Pulmonary hypertension can develop in patients with lcSSc (and occasionally those with diffuse). In pulmonary hypertension, impaired blood flow through the lungs due to the narrowing of the lung’s blood vessels causes shortness of breath.

Limited cutaneous systemic sclerosis was previously known as CREST syndrome.

The acronym “CREST” refers to the five common symptoms of lcSSc: Calcinosis, Raynaud’s Phenomenon, Esophageal dysfunction, Sclerodactyly, and Telangiectasia. (Learn what these words mean in the “Key Terms” page of the Learn Center!) Some patients with diffuse scleroderma will also develop calcinosis and telangiectasias.

Diffuse scleroderma often progresses more rapidly.

Skin thickening typically occurs more rapidly and involves more skin areas in patients with dcSSc than in patients with the limited form. Patients with dcSSc have a higher risk of developing pulmonary fibrosis, also known as interstitial lung disease; in pulmonary fibrosis, scar tissue in the lungs interferes with breathing. Kidney involvement also occurs more frequently in dcSSc patients, especially in the first five years after diagnosis, and usually takes the form of a sudden blood pressure increase. If untreated, this high blood pressure can damage the kidney in a matter of weeks; thus, it is called a scleroderma renal crisis. The likelihood of extensive gut involvement (slowing of stomach/bowel movement or motility) is higher in those with the diffuse form. Patients may feel bloated after eating, have diarrhea, or have alternating diarrhea and constipation.

Several symptoms occur in both the limited and diffuse forms.

These clinical features include Raynaud’s Phenomenon, painful finger ulcers, and loss of the usual esophagus movement (causing heartburn).

Scleroderma sine sclerosis is extremely rare (only about 5% of all cases).

In this unusual form of SSc, the internal organ complications of SSc occur, but there is no skin thickening.