Cutaneous vasculitis

Abstract

Cutaneous vasculitides are inflammatory diseases starting at and evolving around the blood vessels of the skin. They should be separated from occluding vasculopathies, where the pathological process predominantely starts in the blood. They can be graded according to their relationship to systemic vasculitides as a cutaneous component of a systemic vasculitis, as a skin-dominant variant of a systemic vasculitis or as a cutaneous single organ vasculitis. Diagnostic measures, therapy and prognoses depend greatly on this relationship. For diagnostic purposes, a classification based on histopathological features in asscociation with clinicopathological correlation seems most reliable. We differentiate according to vessel size (small-medium-large) and involved cell types (leukocytes, macrophages) as well as extravascular features (necroses, granulomas). Thus, the similarities and overlaps between different manifestations become apparent.

Vasculitides and occluding vasculopathies, challenges in recognizing histopathological patterns, and their solutions

“…Second, some authors do not clearly distinguish between primary vasculitis and coagulopathy which has important therapeutic consequences ( 41 , 42 ); classical vasculitides are treated with the immunosuppressive agents; microorganism-associated vasculitides need specific antimicrobial therapy; and coagulopathies require anticoagulants. Third, vasculitides can present a relatively benign single-organ (e.g., cutaneous) disease or systemic disease with an impaired prognosis ( 13 , 21 – 23 , 27 , 43 , 44 ). The different tissues from organ to organ lead to varying pathologic processes (e.g., hemorrhage is a common manifestation in the affected loose tissue of the lung; or the accumulation of capillary loops makes glomeruli a predisposed area for vascular disease, most commonly seen in leukocytoclastic vasculitis) impeding a precise comparison of morphologic findings ( 12 ).…”