Urticarial vasculitis (UV) is considered a clinicopathologic entity consisting of two elements:
- Clinical manifestations of urticaria
- Histopathological evidence of cutaneous leukocytoclastic vasculitis (LCV) of the small vessels, largely involving the postcapillary venules [1-4]
Although UV is most commonly idiopathic, it can occur in association with autoimmune diseases, drug reactions, infections, or malignancy. UV may be systemic or localized to the skin . Hypocomplementemia, when present, may be associated with extensive vasculitis and systemic features that most commonly involve the musculoskeletal, pulmonary, renal, and/or gastrointestinal systems. Discussion of this topic is confounded by the lack of accepted criteria for distinguishing UV from other cutaneous vasculitides and associated conditions.
A detailed literature review of this subject has been published by the authors . The epidemiology, clinical features, laboratory and biopsy findings, differential diagnosis, treatment and prognosis of UV are reviewed here. A more general discussion of urticaria and related conditions is presented elsewhere. (See "Chronic urticaria: Clinical manifestations, diagnosis, pathogenesis, and natural history".)
UV is characterized by a variety of cutaneous, systemic, and serologic features, which have resulted in a confusing array of names for this disorder(s).