About Systemic Sclerosis

Systemic sclerosis (SSc) is a systemic autoimmune disease with characteristic interstitial, vascular fibrosis in the skin +/- internal organs.

Differential Diagnosis

  • If there is no Raynaud’s and/or ANA is negative, SSc is rarely the diagnosis!  
  • Scleroderma renal crisis (SRC): usually with diffuse SSc and early on in disease (first 5 yrs) – presents with sudden increase of BP
  • Labs: creatinine increase, MAHA
  • ACEi rx

Treatment & Monitoring

  • Avoid high dose glucocorticoids due to risk of renal crisis: steroids do not decrease skin tightening
  • Interstitial lung disease (ILD) carries high mortality and seen more with anti-Scl-70
  • Pulmonary HTN is high cause of death for limited SSc
  • Close monitoring of BPs and serial TTEs and PFTs are key

Key Subtypes

Limited SSc (lSSc)
Diffuse SSc (dSSc)
  • Skin tightening in proximal extremities and trunk
SSc Sine Scleroderma
  • SSc antibodies
  • Internal organ involvement
  • No skin tightening
Localized Scleroderma (skin limited)
  • Morphea
  • Linear scleroderma

Evaluation Guide

  • Concern for systemic? Extradermal?
  • Pattern of skin dz? Diffuse or limited to extremities?
  • What internal organs involved?
    • Raynaud’s (view image)
    • Esophageal
    • Lung: ILD: PFTs, high-res CT w/o contrast (view image), chest 
    • pHTN: DLCO, TTE
    • Renal: Scleroderma renal crisis (SRC)
    • Heart
    • Myositis

Basic Labs

  • CBC (anemia of chronic disease, MAHA)
  • CMP
  • ESR/CRP
  • Urinalysis

SSc Serologies

  • ANA (80-90%)
  • SCL70/topoisomerase: dSSc
  • Centromere: lSSc
  • RNA polymerase III: SRC
  • Scleredema (DM2)
  • Scleromyxedema (malignancy?)
  • Perineoplastic?
  • POEMS
  • Chronic graft vs. host disease
  • Nephrogenic systemic fibrosis
  • Eosinophilic fasciitis
  • Amyloidosis
  • Drug exposure (e.g., bleomycin)
  • Environmental exposure (organic solvents, etc.)
  • Highly recommend rheumatology referral before initiating treatment
  • Treatment is based on extent of skin disease, organs involved, severity of disease
    • Avoid prednisone >=20 mg (associated with scleroderma renal crisis [SRC])
  • Skin fibrosis: consider methotrexate (MTX), mycophenolate (MMF)
  • Raynaud’s: CCB, PDE5-inhibitor
  • Arthritis: hydroxychloroquine (HCQ), MTX
  • Interstitial lung disease (ILD): MMF, cyclophosphamide, anti-fibrotics
  • Renal crisis: ACEi
  • pHTN treatment
  • GERD/dysphagia: PPI, reflux rx, GI referral
  • Manage BP to decrease risk of renal crisis
  • SRC is an emergency!
  • Extra-derm disease:
    • ILD (view image)
    • pHTN
    • Renal crisis (20% of dSSc, 5% of lSSc)
    • Myopericarditis
  • CBC, CMP: monitored for drug toxicity and disease activity
  • Follow-up testing for organs of concern: PFTs with DLCO, TTE, CT chest, GI scope
  • Cancer screening