Cutaneous pathology in Wegener's granulomatosis. A clinicopathologic study of 75 biopsies in 46 patients.

While no cutaneous lesion is specific for Wegener's granulomatosis (WG), several histopathologic entities, including leukocytoclastic vasculitis and necrotizing granulomatous inflammation, are characteristic. This report details the histopathologic features of 75 cutaneous biopsies from 46 patients with WG. Biopsies were subdivided into histologic groups that included leukocytoclastic vasculitis (31%), granulomatous inflammation (GI) (19%), nonspecific ulceration (4%), superficial dermal and epidermal necrosis without inflammation (2.7%), erythema nodosum (2.7%), granuloma annulare (1%), chronic inflammation (31%), and acute inflammatory lesions without vasculitis (9%). No convincing example of granulomatous vasculitis was observed. The histopathologic subgroups were correlated with clinical features, and the results were compared with those from a control group of 82 WG patients with no skin involvement. We found that the histopathologic subgroups of leukocytoclastic vasculitis and granulomatous inflammation correlated with different clinical courses. Patients with leukocytoclastic vasculitis developed WG at an earlier age (median age, 30 years) than did the control group (median age, 45 years). Leukocytoclastic vasculitis developed shortly after onset of WG (median, 15 months vs. 35 months for patients with nonspecific chronic inflammation). All lesions occurred during active disease. Active disease with leukocytoclastic vasculitis was associated with a mean erythrocyte sedimentation rate twice that of active disease in the same patient when leukocytoclastic vasculitis was absent. The patients with leukocytoclastic vasculitis had more rapidly progressive and widespread WG than patients with granulomatous skin lesions or patients without skin lesions. A marked excess of joint and musculoskeletal symptoms and renal disease was seen in patients with leukocytoclastic vasculitis. Patients with granulomatous inflammation also developed WG at an early age (median age, 30 years) when compared with the control group. Cutaneous granulomatous lesions also developed shortly after presentation (median, 12 months). Only 64% of granulomatous biopsies were from patients with active disease. These patients frequently had neither renal nor pulmonary manifestations of WG, and their disease progressed at a slower rate than that of the patients with leukocytoclastic vasculitis. These findings suggest that the cutaneous lesions characteristic of WG may correlate with the activity, distribution, and course of the disease.