Eosinophils within blood vessel wall in a patient with EGPA

This biopsy demonstrates the presence of eosinophils within the blood vessel wall of a patient with eosinophilic granulomatosis with polyangiitis (EGPA; Churg-Strauss). Although eosinophils are the hallmark of EGPA, this biopsy does not show fibrinoid necrosis of the blood vessel wall and hence is not diagnostic of vasculitis.