Limited Cutaneous Systemic Sclerosis

Limited cutaneous systemic sclerosis (lcSSc) is a subtype of systemic sclerosis (SSc; see this term) characterized by the association of Raynaud's phenomenon with skin fibrosis limited to the hands, face, feet and forearms.

Epidemiology

The prevalence is estimated at about 1/12,500 adults. Women are predominantly affected (F/M sex ratio around 4:1).

Clinical description

Women are predominantly affected (F/M sex ratio around 4:1). The disease usually manifests at between 40 and 50 years of age. Raynaud's phenomenon is the most common and often the first sign of the disease. The other signs usually appear some years later. Skin involvement is limited to the hands, face, feet and forearms. Skin tautness is absent in the chest, abdomen, back, or thighs. Telangiectasias and sclerodactyly with a risk of digital ulcers are observed. Esophageal dysmotility is common, and provokes gastroesophageal reflux and sometimes dysphagia. About 30-40% of the patients have lung fibrosis on computed tomography (CT) scan and about 10% have pulmonary arterial hypertension. In some early stages of the disease, cutaneous involvement is not yet present; as a consequence the disease is called limited SSc. In rare situations, cutaneous involvement never occurs; as a consequence, the disease is called SSc sine scleroderma. CREST syndrome (see this term) is usually considered a synonym of limited cutaneous SSc but it is rather a subtype with more frequent and more extended telangiectasias.

Etiology

The exact cause of limited cutaneous SSc is unknown. The disease originates from an autoimmune reaction which leads to overproduction of collagen. In some cases, the condition is associated with exposure to chemicals (including silica, solvents and hydrocarbons).

Diagnostic methods

Diagnosis is based on typical clinical manifestations and on evidence of specific microangiopathy with giant loops on nailfold capillaroscopy. Blood tests show a high incidence of anticentromere antibodies (ACA). The extent of the disease should be evaluated by CT, electrocardiogram, echocardiography, radiography of the hands and esophageal and gastric fibroscopy if needed.

Differential diagnosis

Differential diagnoses include Sharp syndrome, systemic lupus erythematosus, antiphospholipid syndrome, and polyarteritis nodosa (see these terms).

Management and treatment

Management is mostly symptomatic. Raynaud's phenomenon can be treated with calcium channel blockers. Proton pomp inhibitors are given for gastric reflux. Patients require regular clinical follow-up with early pulmonary function tests and echocardiography. Low doses of corticosteroids with immunosuppressive agents are needed in cases with progressive lung fibrosis. Pulmonary vasodilators are given in case of pulmonary arterial hypertension.

Prognosis

The prognosis of limited cutaneous SSc is relatively good with a long-lasting disease duration (10-year survival rate is about 80 to 90%). However, pulmonary arterial hypertension may be a complication of the disease (in about 10% of cases) and may lead to a more severe prognosis. Severe lung fibrosis may occur in some patients.