Systemic lupus erythematosus and other collagen vascular diseases

Introduction: the causal diseases Definitions and epidemiology Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with variable clinical manifestations, characterized by widespread inflammation of blood vessels and connective tissue. The presence of antinuclear antibodies (ANA), especially antibodies to native (double-stranded) DNA (dsDNA) is characteristic. It is a rare disease with an incidence among adults of 2.0 per 100000 per year; few studies on children estimate an annual incidence between 0.36 and 0.6 per 100000 with a higher rate in girls. The term vasculitis indicates the presence of inflammation in a blood vessel wall. It includes a number of diseases which can be classified by the size of the vessels affected as: large-vessel vasculitis (giant cell arteritis, Takayasu's arteritis), medium-vessel vasculitis (polyarteritis nodosa; Kawasaki disease), and small-vessel vasculitis (Wegener granulomatosis, Churg–Strauss syndrome, microscopic polyangiitis, Henoch-Schönlein purpura, cryoglobulinemic vasculitis, cutaneous leukocytoclastic angiitis). Scleroderma is a disorder characterized by an excessive accumulation of collagen in the skin and can be subdivided into localized and systemic forms. It is quite a rare disease with an incidence of 2.7 cases per 100000 per year. Its pathogenesis is still unknown but dysfunction of the immune system plays a prominent role. Some authors consider the endothelial cell injury the central pathogenic event; endothelial cells and fibroblasts may present integrines on their surface facilitating mononuclear cell damage. Moreover an increased number of collagen-producing fibroblasts and a defect in the regulation of genes controlling apoptosis of fibroblasts have been reported.