Systemic sclerosis

Abstract

The term ’scleroderma’ describes a group of conditions in which the development of thickened, fibrotic skin is a cardinal feature. This includes localized forms of scleroderma (e.g. morphoea) and also systemic forms of the disease that are more correctly termed systemic sclerosis. Systemic sclerosis (SSc) is a multiorgan, autoimmune disease that has a high clinical burden and mortality, due to affecting the skin as well as internal organs. As with other related diseases there is a female predominance and marked clinical diversity. The pathogenesis of SSc is not fully elucidated; it includes endothelial cell injury fibroblast activation and autoimmunity that lead to skin and internal organ manifestations. The majority of cases exhibit characteristic serum autoantibodies. Some of these antibodies are scleroderma-specific reactivities including anti-centromere (ACA), anti-topoisomerase-1 (ATA or Scl 70) or anti-RNA polymerase III antibodies. These anti-nuclear antibody (ANA) patterns are generally mutually exclusive and serve as useful clinical markers of disease subgroups. Additional subsetting of scleroderma cases, based on the extent of skin sclerosis, permits classification into limited and diffuse subsets. Because of the heterogeneity of the disease patients may suffer from different organ manifestations, such as lung fibrosis, hypertensive renal crisis, severe cardiac disease, gastrointestinal involvement, and pulmonary arterial hypertension. Although outcomes have improved recently, systemic sclerosis still has the highest case-specific mortality of any of the autoimmune rheumatic diseases and requires careful and systematic investigation, management and follow-up. Treatment includes symptomatic strategies with attention to each involved organ system; it is still an area where therapeutic progress and better understanding of pathogenesis is increasingly anticipated.