Systemic Sclerosis Clinical Manifestations and Diagnosis

Disease Classification and Initial Presentation

Systemic sclerosis (SSc) is characterized by the extent of skin involvement, with limited cutaneous SSc (lcSSc) involving skin distal to elbows/knees, and diffuse cutaneous SSc (dcSSc) involving both distal and proximal areas including the trunk 1
Some patients (1.5-8%) present with SSc sine scleroderma, lacking definite skin involvement but developing major internal organ complications 1
"Prescleroderma" may present with isolated Raynaud phenomenon, puffy fingers, specific autoantibodies, or SSc-associated capillaroscopic changes 1

The modified Rodnan skin score (mRSS) measures skin thickness on a scale of 0-3 at 17 anatomical sites (score range 0-51) 2
In dcSSc, skin thickening typically increases over the first 4 years of disease and may regress somewhat thereafter 2

Interstitial lung disease (ILD) is common (40-75% based on lung function changes) but progressive in 15-18% of patients 1
Screening for ILD includes history, physical examination, chest radiography, pulmonary function testing, and high-resolution CT when appropriate 3
Patients positive for anti-topoisomerase 1 (Scl-70) antibodies have a higher frequency of ILD 4
Pulmonary arterial hypertension (PAH) risk increases with longer disease duration, older age, and/or low diffusing capacity 4

Scleroderma renal crisis (SRC) occurs predominantly in early dcSSc 4
Patients positive for anti-RNA polymerase III antibodies (anti-RNAPIII) are at high risk for SRC 4
Risk factors for SRC include male sex, tendon friction rubs, rapidly progressive skin involvement, and glucocorticoid use 4

Gastrointestinal involvement affects nearly 90% of SSc patients 1
The esophagus is most commonly involved, followed by small bowel, colon, and anorectum 1
Malnutrition is the leading cause of mortality attributed to GI tract involvement 1

Screen for cardiac involvement if arrhythmias and/or heart failure are present 4

SSc can overlap with other connective tissue diseases including SLE, dermatomyositis, polymyositis, and Sjögren syndrome 4
3% of SSc cases overlap with rheumatoid arthritis 4
Primary biliary cholangitis occurs in 8% of lcSSc cases, usually in anti-centromere antibody positive patients 4

Autoantibody profile is crucial for risk stratification and prognosis 4
Key antibodies include anti-topoisomerase 1 (Scl-70), anti-centromere, and anti-RNA polymerase III 4
For overlap syndromes, test for extractable nuclear antibodies (RNP, SSA/Ro, SSB/La, Smith, Jo1, PM/Scl-70) 4

Screen for malignancy if patient has rapidly progressive dcSSc with weight loss, especially in elderly patients 4
Anti-RNAPIII positivity increases malignancy risk 4
Other associations with malignancy include ILD, cyclophosphamide use, and autologous hematopoietic stem cell transplantation 4

Screen for depression, which is elevated in SSc patients 4
Osteoporosis risk is increased; consider bone density scanning 4
Erectile dysfunction is frequent in men with SSc 4
Assess cardiovascular risk factors including hypertension, diabetes mellitus, hyperlipidemia, and metabolic syndrome 4

Myositis or myopathy affects about 15% of patients, and those with skeletal myopathy are 2.5 times more likely to have heart failure or arrhythmias, according to the American Heart Association 5
Pericardial effusions can manifest with muffled heart sounds or pericardial rub, as noted by the American College of Cardiology 5