Figure 1.
Segmental acute necrotizing ANCA-associated vasculitis lesions with (a–c) fibrinoid necrosis (hematoxylin and eosin stain) (large arrow) and (a,c) leukocytoclasia (small arrow). (a,b) The inflammatory infiltrate includes a mixture of neutrophils and mononuclear leukocytes. (c,d ) A Masson trichrome stain is useful in distinguishing between (b) acute segmental fibrinoid necrosis and (d) chronic segmental sclerosis.