Systemic Sclerosis

Systemic connective tissue autoimmune disease characterised by vasculopathy, autoimmunity and fibrosi; categorized into limited SSc and diffuse SSc

Aetiology

• Higher indicence in females

• Peak incidence 30-50 years

• Genetic predisposition + environmental trigger

Pathophysiology

1. Etiological agent + genetic predisposition

2. Endothelial cell and vascular alterations

3. Chronic inflammation

4. Vascular damage (vasculopathy) and tissue fibrosis → skin involvement, organ damage

Limited systemic sclerosis

• Skin involvement tends to be confined to the face, hands, forearms and feet

• In 90% of cases, Raynaud phenomenon precedes the onset of other symptoms

• Organ involvement tends to occur later

• Anti-centromere antibody (ACA) association

Diffuse systemic sclerosis

• Skin changes develop more rapidly and can involve the trunk

• Raynaud phenomenon often coincides with or follows the onset of other symptoms

• Early significant organ involvement

• Anti-SCL-50 antibody and anti-RNA polymerase III association

Clinical presentation

Symptoms

• Thickening and hardening of the skin

• Sclerodactyly - thickening of the skin of the fingers and hands which can cause loss of dexterity of hands

• Raynaud's phenomenon
• The result of vascular spasms that reduce the blood supply to the fingers, usually when the hands get cold
• The fingers will go white (blanching), then blue (acrocyanosis), then as they warm up, or the episode passes, they will become red (reactive hyperaemia)

• Multiple, painful ischaemic digital ulcers (caused by Raynaud's)

• Fatigue, weakness

• Joint stiffness/pain

Signs

• Calcinosis of the fingertips

• When the skin of the face is involved:
• Pinching of the skin of the nose - 'beaking'
• Tightening of the skin around the mouth - small mouth with 'puckered lips'
• Telangectasia
• Lack of wrinkles

Organ involvement

• Arthralgia and myalgia

• Oesophageal dysmotility → dysphagia and reflux

• Small bowel dysmotility → bloating, gas, constipation, cramping

• Pulmonary hypertension

• Interstitial lung disease - dyspnoea, bilateral fine inspiratory crackles, cough

• Fibrosis, myocarditis, pericarditis

• Pulmonary hypertension can cause right sided heart failure

• Non-specific progressive renal dysfunction - due to microvascular changes and fibrosis

• Scleroderma renal crisis
• Uncontrolled hypertension with proteinuria and rapidly worsening renal function
• Associated with anti RNA polymerase III antibody
• Usually early in disease (presenting feature)
• High dose of steroids puts people at risk (incidence decreasing as steroids are used less now)

Investigations

Autoantibodies

• ANA present in 90% of cases (but not very specific)

• Limited SSc: anti-centromere antibody (ACA) - associated with vasculopathy complications

• Diffuse SSc: anti-topoisomerase (SCL-7) (associated with fibrosis complications) and anti RNA polymerase III (associated with renal involvement)

Pulmonary complications

• SSc patients should be screened yearly for pulmonary complications

• Pulmonary arterial hypertension - echo

• Pulmonary fibrosis - PFTs
• If PFTs restrictive - high resolution CT (honeycombing = fibrosis)

Management

• No overall treatment, management tends to be tailored to the specific issues

Non-medical management

• Avoid smoking

• Gentle skin stretching to maintain the range of motion

• Regular emollients

• Avoiding cold triggers for Raynaud’s

• Physiotherapy to maintain healthy joints

• Occupational therapy for adaptations to daily living to cope with limitations

Medical management 

• Nifedipine can be used to treat symptoms of Raynaud’s phenomenon

• Anti acid medications (e.g. PPIs) and pro-motility medications (e.g. metoclopramide) for gastrointestinal symptoms

• Analgesia for joint pain

• Antibiotics for skin infections

• Antihypertensives can be used to treat hypertension (usually ACE inhibitors)

• Treatment of pulmonary artery hypertension

• Supportive management of pulmonary fibrosis