The Differential Diagnosis of Systemic Sclerosis

Conclusion

In summary, diffuse thickening of the skin may be an early presentation of SSc, but other rarer conditions need to be excluded. The distribution of skin involvement, presence or absence of microvascular changes, autoantibodies, especially antinuclear antibodies, and the scleroderma-specific subgroups (anticentromere, Scl-70 and RNA polymerase) and increased mucin or eosinophils in the skin biopsies guide the diagnosis (see list below). Rapid exclusion of other disorders allows an early treatment intervention for SSc. Some diagnostic 'tips' regarding diffuse skin thickening syndromes are as follows:

1. 
   1. diffuse cutaneous mucinoses:
   
   1. 
      scleromyxoedema;
      
   2. 
      scleroedema adultorum Buscke;
      
   3. 
      generalized myxoedema of hypothyroidism;
      
   4. 
      pretibial myxoedema of hyperthyroidism;
      
   5. 
      NSF;
      
   
   
2. 
   paraprotein:
   
   1. 
      scleromyxoedema (mostly);
      
   2. 
      scleroedema (sometimes);
      
   
   
3. 
   face sparing:
   
   1. 
      NSF;
      
   
   
4. 
   Raynaud's/capillaroscopy/ANA:
   
   1. 
      SSc and CTD.