Vasculitis in chronic urticaria

We have explored the problem of the histologic basis of chronic urticaria and its relation to vasculitis and immune complex disease. In a prospective study, 42 consecutive patients with chronic urticaria (from twice weekly to daily episodes lasting more than 6 wk) had skin biopsies and were studied for immunologic variables. Twenty-two patients (52%) had vasculitis on biopsy as defined by the presence of cellular infiltrates within the vessel wall. The other 20 patients (48%) had either edema only or perivascular infiltrates with mononuclear cells (perivasculitis). The group with vasculitis could be subdivided into seven patients with neutrophilic venulitis including three with fibrinoid change, seven with mixed-cellular vasculitis, four with lymphol monocytic vasculitis, and four with eosinophilic vasculitis. Vascular deposits of immunoreactants were found in only four (18%) of the vasculitis patients, compared with 65% of concurrently studied patients who had cutaneous venulitis manifested as palpable purpura, i.e., Henoch-Schönlein syndrome. Urticarial patients with vasculitis were more often male and had a longer mean duration of hives compared with the nonvasculitis group. We saw no differences between the vasculitis and nonvasculitis cases of urticaria with regard to the incidence of arthralgia, elevated erythrocyte sedimentation rate (ESR), or hypocomplementemia. The group with vasculitis did not have more generalized disease nor were the hives more resistant to therapy. We have discussed the definition and histologic criteria for the diagnosis of vasculitis when it occurs in very small blood vessels.