Patients with vasculitis may complain of burning or pain in the affected areas. The condition is often accompanied by systemic involvement, manifested as arthralgias, myalgias, fever, abdominal pain, or hematochezia. Palpable purpura is the most common cutaneous sign (Fig. 62-1). However, urticarial lesions, ulcerations, nodules, or livedo reticularis (a bluish discoloration in a net pattern) can also occur. Palpable purpura or urticarial lesions are more common in small blood vessel disease, whereas medium-sized vessel involvement manifests as livedo reticularis, nodules, or ulcers. Vasculitis may be a sign of many underlying conditions, including infections (e.g., bacterial endocarditis, acute respiratory infections, or hepatitis B or C), drug reactions (from aspirin, penicillin, sulfonamides, or others), cryoglobulinemia, collagen vascular disorders (e.g., systemic lupus erythematosus, rheumatoid arthritis, or Sjögren’s syndrome), lymphoproliferative disorders, and Henoch–Schönlein purpura.