Scleroderma is a heterogeneous condition characterised by progressive fibrosis, widespread vascular disease and immunological abnormalities. It is divided into limited cutaneous disease (formerly known as CREST syndrome) and diffuse cutaneous disease (or systemic sclerosis).

Limited cutaneous disease

A relatively benign form of the disease affects the majority of patients with scleroderma syndromes. It is characterised by limited skin involvement and late appearance (if any) of visceral complications.

• Cutaneous manifestations are the result of overproduction of connective tissue, classically collagen. The skin becomes bound-down, taut, crease-free and hairless. The classic changes occur in the fingers (sclerodactyly) with loss of the finger pulp, development of flexion contractures and reduced movement. This type of contiguous skin change does not extend beyond the elbow or knee in the limited form of the disease. Additional patterns of cutaneous disease include small, localised and circumscribed areas (morphoea), linear streaks frequently following a dermatomal distribution, or en coup de sabre, in which the face and scalp are involved. Calcinosis is also a common occurrence.
  
• Vascular abnormalities include Raynaud’s phenomenon, telangiectasia and capillary nail fold abnormalities. Digital ischaemia and ulceration can occur late in the disease.
  
• Gastrointestinal involvement is limited to oesophageal dysmotility leading to dysphagia and reflux. More distal disease is rare.
  
• Pulmonary hypertension occurs as a result of interstitial fibrosis, pulmonary vascular disease or both.

Note that limited cutaneous scleroderma is now preferred to CREST syndrome (Calcinosis, Raynaud’s phenomenon, Esophageal dysmotility, Sclerodactyly and Telangiectasia).

Diffuse cutaneous disease

The complications of diffuse disease are universally more severe.

• Cutaneous manifestations spread proximally to include the trunk and face and patients develop a characteristic appearance with taut skin, a beaked nose and a tight mouth (microstomia) with restricted opening.
  
• Vascular disease is characterised by a renal obliterative endarteritis, which can precipitate a life-threatening renal hypertensive crisis.

• The entire gastrointestinal tract may become involved. The hypomobility generated by increasing fibrosis causes: