Abstract
Wegener’s granulomatosis and Churg–Strauss syndrome are the two primary systemic necrotizing vasculitides that are most typically characterized by granulomatous inflammation of small vessel walls. The skin may be involved in both, with biopsies often showing nonspecific leukocytoclastic vasculitis but also, in some cases, granulomatous vasculitis and/or extravascular granulomas. Such lesions can also be seen, but rarely, in Takayasu’s arteritis and giant-cell arteritis, which are large-vessel vasculitides. At onset, these systemic vasculitides usually have other severe systemic and/or organ-specific symptoms that contribute to achieving the diagnosis. However, other diseases or conditions can also be associated with cutaneous granulomatous vasculitis and/or extravascular granulomas and have to be considered in the differential diagnosis, for instance, lymphomatoid granulomatosis, lymphoproliferative hemopathies, inflammatory and autoimmune diseases, such as rheumatoid arthritis or systemic lupus erythematosus, inflammatory bowel disease and, rarely, infections with herpes simplex, varicella-zoster or hepatitis C virus.