The Churg-Strauss granuloma: cutaneous, necrotizing, palisading granuloma in vasculitis syndromes.
The cutaneous, necrotizing, palisading granuloma (Churg-Strauss granuloma) was observed on histopathologic study of skin specimens from seven patients. Two patients had Wegener's granulomatosis and one patient each had allergic granulomatosis, limited Wegener's granulomatosis, bacterial endocarditis, systemic lupus erythematosus, and rheumatoid arthritis. The microscopic picture consists of extravascular, palisading, dermal granuloma. The center of the granuloma consists of basophilic fibrillar necrosis in which linear bands of destroyed tissue are interspersed with masses of polymorphonuclear leukocytes and leukocytoclastic debris. This necrotic leukocytic mass is surrounded by histiocytes and some lymphocytes. The clinical lesions are symmetric, erythematous papules or nodules on the extremities. The histopathologic picture of the Churg-Strauss granuloma is unique and, as demonstrated in these cases, indicates the presence of systemic vasculitis.