Scleroderma or systemic sclerosis (SSc) is a term used to describe a connective tissue disorder that is characterized by thickening and fibrosis of the skin.
Localized scleroderma and systemic sclerosis. Localized scleroderma is skin thickening without any organ involvement and includes three subset conditions. Morphea. Linear scleroderma. Scleroderma en coup de sabre.
Systemic sclerosis is a multiorgan disease characterized by fibrosis and vasculopathy. Systemic sclerosis includes skin fibrosis along with variable severe involvement of diverse internal organs.
It is further divided into two major subgroups:
(1) Limited cutaneous SSc (lcSSc), which involves skin thickening of the face, neck, and distal to the elbows and knees; and
(2) diffuse cutaneous SSc (dcSSc), which affects the skin in a more generalized distribution including the proximal and distal extremities, face, neck, and trunk. Clinical features of the major subsets of systemic sclerosis are summarized:
Limited SSc:
Skin sclerosis, distal limbs, and face
Long preexisting RP symptoms
Lower frequency of severe lung fibrosis and renal crisis
High burden of nonlethal morbidity
Diffuse SSc:
Proximal skin sclerosis
Shorter preexisting RP history
High frequency of severe lung fibrosis
Increased risk of scleroderma renal crisis
Inflammatory skin changes and pruritus common for first 1-3 yr
Sine SSc:
Features of RP with scleroderma-associated ANA reactivity and at least one internal organ manifestation of SSc
Frequency uncertain because of likely underdiagnosis
Overlap SSc:
Cases that fulfill classification criteria for SSc and that are diagnosed as SSc but also show features of another autoimmune rheumatic disease
Most often myositis
Other cases of lupus, arthritis, or vasculitis
Comprise up to 20% of SSc cohorts