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Erythema elevatum diutinum (EED) is a chronic leukocytoclastic vasculitis (LCV) that was initially described by Hutchinson in 1888 and subsequently by Bury in 1889. The name EED was first used by Radcliff-Crocker and Williams who separated it into two groups.1–3 The Bury type tended to occur more commonly in younger women with a history of underlying rheumatologic disease, and the Hutchinson type tended to occur in elderly males.
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The incidence of EED is unknown; however, it appears to be a rare disease. There is no significant mortality associated with EED. It presents predominantly in males, in the fourth to sixth decade of life.
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The pathogenesis of EED is not entirely clear; however, the prevailing and traditional theories are based on immune complex deposition within vessel walls, complement fixation, inflammation, and subsequent vascular destruction.1 The various disease associations seen in EED (see Section “Associated Diseases”) have provided further understanding of the underlying pathomechanism of EED.
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Antineutrophil cytoplasmic antibodies (ANCA) of the immunoglobulin G (IgG) type have proven useful for the diagnosis and monitoring of disease activity in various systemic vasculitides, including granulomatosis with polyangiitis (Wegener's), microscopic polyangiitis (MPO), polyarteritis nodosa, and Churg–Strauss syndrome.4
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There are reports in the literature documenting the occurrence of IgA ANCAs in patients with neutrophil-driven dermatoses such as Henoch–Schönlein purpura, inflammatory bowel disease, and various cutaneous vasculitides, including EED.5,6 It seems likely that abnormal functioning or activation of the neutrophil, which is the primary inflammatory cell in EED, may represent the central event. Most importantly, some of the neutrophilic dermatoses, including EED, have been associated with underlying paraproteinemias (monoclonal and polyclonal IgA gammopathies)7 and hematologic malignancies. The severity of EED does not, however, appear to be dependent on the total paraprotein levels. Nevertheless, immunoelectrophoresis screening for monoclonal gammopathies as a marker of EED has been recommended.8 Hence, IgA ANCAs against yet unidentified neutrophilic antigenic targets may prove to be useful clinical markers in EED.9
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In a recent analysis of the clinical, histopathologic, and immunohistochemical features in six patients with EED by Wahl et al,8 the vascular endothelium of EED was immunoreactive for CD31, CD34, vascular endothelial growth factor, and factor VIIIa but nonimmunoreactive for factor XIIIa, transforming growth factor-β, and latency-associated nuclear antigen of human herpesvirus 8. The staining properties of the endothelium in EED were ...