The assessment of any patient for possible vasculitis includes a thorough evaluation for other conditions that mimic vasculitis, particularly those in which corticosteroid and immunosuppressive treatment may be more harmful than beneficial. Calciphylaxis, which may be more common than previously recognized, is a syndrome associated with the development of painful skin nodules, often in a livedo reticularis pattern, skin necrosis and ulceration, myalgias, and elevated creatine kinase levels. Usually found in patients with chronic renal failure, the pathology is a distinctive mural calcification of small blood vessels. An incisional skin biopsy will reveal histologic findings of calcification within the media of small dermal blood vessels with superimposed intimal fibroblastic proliferation, causing marked luminal narrowing. Muscle biopsy specimens may also demonstrate calcium deposits within the walls of small perimysial vessels with intimal proliferation. Correction of calcium phosphate product, meticulous wound care, debridement if needed, and antibiotic therapy are essential, but the disease is associated with a high degree of morbidity and mortality. A parathyroidectomy may be beneficial. It has been suggested that corticosteroids and immunosuppressive agents may aggravate the condition. Awareness of this syndrome by rheumatologists will lead to proper diagnosis and treatment.