[Cutaneous vasculitides. A diagnostic approach].

Vasculitis is characterized by an inflammatory reaction of vessel walls with damage to the dependent tissues. Forms of vasculitis which frequently have skin changes include leukocytoclastic angiitis (LcV), Henoch-Schönlein purpura (HSP), cutaneous polyarteriitis nodosum (cPAN), erythema elevatum et diutinum (EED) and urticarial vasculitis (UV). In other forms of vasculitis, systemic manifestations predominate but there are a variety of skin changes. Kawasaki disease (MK), cryoglobulinemic vasculitis (kV), Wegener granulomatosis (WG), Churg-Strauss syndrome (CSS) and microscopic polyangitis (MPA) belong to this group. The causes of vasculitis are heterogeneous. Triggers include infections, drugs, collagen vascular diseases, autoimmune diseases and lymphoproliferative disorders. Idiopathic vasculitis, particularly LcV and EED, occur only once and have a self-limited course. The diagnostic work up depends on the clinical picture and includes inflammatory markers, circulating immune complexes, different types of cryoglobulins and anti-neutrophilic cytoplasmic antibodies, collagen vascular disease specific autoantibodies and additional hematological studies. Vasculitis can manifest in many organs and requires a thorough work up specifically in cases where WG, MPA, CSS and PAN are under consideration.