Scleroderma (Systemic Sclerosis)

Key Features

Essentials of Diagnosis

• A rare chronic disorder characterized by diffuse fibrosis of the skin and internal organs

• In limited disease (80% of patients): thickening of skin confined to the face, neck, distal extremities

• In diffuse disease (20%): widespread thickening of skin, including truncal involvement, with areas of increased pigmentation and depigmentation

• Raynaud phenomenon and antinuclear antibodies are present in virtually all patients

• Systemic features of gastroesophageal reflux, hypomotility of gastrointestinal tract, pulmonary fibrosis, pulmonary hypertension and renal involvement

General Considerations

Limited

• Also known as the CREST syndrome (representing calcinosis cutis, Raynaud phenomenon, esophageal motility disorder, sclerodactyly, and telangiectasia)

• The hardening of the skin (scleroderma) is limited to the face and hands

• Patients with limited disease are more susceptible than those with diffuse disease to

  • Digital ischemia, leading to finger loss

  • Life-threatening pulmonary hypertension

Diffuse

• Skin changes also involve the trunk and proximal extremities

• Tendon friction rubs over the forearms and shins

• Cardiac disease is also more characteristic of diffuse scleroderma

Demographics

• Symptoms usually appear in the third to fifth decades

• Women are affected two to three times as frequently as men

Clinical Findings

Symptoms and Signs

• Skin

  • Most frequently, skin involvement precedes visceral involvement

  • With time the skin becomes thickened and hidebound, with loss of normal folds

  • Telangiectasia, pigmentation, and depigmentation are characteristic

  • Ulceration about the fingertips and subcutaneous calcification are seen

• Joints

  • Polyarthralgia and Raynaud phenomenon (present in 90% of patients) are early manifestations

• Gastrointestinal tract

  • Dysphagia from esophageal dysfunction (abnormalities in motility and later from fibrosis) is common

  • Fibrosis and atrophy of the gastrointestinal tract cause hypomotility, and malabsorption results from bacterial overgrowth

  • Small and large bowel hypomotility, which may occur in either form of scleroderma, can cause

    • Constipation alternating with diarrhea

    • Malabsorption due to bacterial overgrowth

    • Pseudoobstruction

    • Severe bowel distention with rupture

  • Large-mouthed diverticuli occur in the jejunum, ileum, and colon

• Pulmonary

  • Diffuse pulmonary fibrosis and pulmonary vascular disease are reflected in low diffusing capacity, restrictive lung physiology and pulmonary hypertension

• Cardiac abnormalities

  • Pericarditis, heart block, myocardial fibrosis

  • Right heart failure secondary to pulmonary hypertension

• Renal crisis

  • Results from intimal proliferation of smaller renal arteries and usually associated with systemic hypertension

  • Carries a grave prognosis

Differential Diagnosis

• Several conditions mimic limited systemic sclerosis (generally limited to the skin and typically in a localized fashion)

  • Eosinophilic fasciitis

  • Overlap syndrome ("mixed connective tissue disease")

  • Raynaud disease

  • Morphea

  • Amyloidosis

  • Graft-versus-host disease

  • Cryoglobulinemia

Diagnosis

Laboratory Tests

• Antinuclear antibody tests are nearly always positive (Table 20–7)

• The scleroderma antibody (SCL-70) directed against topoisomerase III is found in one-third of patients with diffuse ...