Urticaria vasculitis

Core Messages: Urticaria vasculitis (UV) is a clinicopathological entity characterized by urticarial papules and plaques lasting longer than 24 h accompanied by histopathologic features of leukocytoclastic vasculitis. Clinical presentation of UV is characterized by urticarial papules or plaques, which can be burning or tender rather than pruritic in 33% of patients, usually persist for more than 24 h leaving residual purpura or hyperpigmentation, and are frequently associated with angioedema. The minimal histopathological criteria for UV have been proposed to include the presence of leukocytoclasis or fibrinoid necrosis in the lesions, irrespective of red blood cell extravasation. A continuum exists in the histopathologic changes of UV, which might reflect the time of evolution of lesions at the moment of biopsy. UV is considered to be due to deposition of immune complexes, which can be found in the circulation of 30-75% of patients. Patients with UV and complement activation are much more likely to have systemic disease than are patients with normocomplementemic UV. As many as 50% have moderate to severe emphysematous chronic obstructive pulmonary disease, and up to 30% have ocular inflammation, particularly uveitis. UV has an unpredictable course, even though the outcome is usually benign in patients with the idiopathic, normocomplementemic form of the disease. © 2010 Springer-Verlag Berlin Heidelberg.