Microscopy
A vessel wall contains an infiltrate of lymphocytes, histiocytes and giant cells (granulomatous vasculitis).
Etiology
Wegener granulomatosis
Churg and Strauss arteritis
necrotizing sarcoidosis
Horton arteritis
Differential diagnosis
lymphomas
lymphomatoid granulomatosis
bronchopulmonary aspergillosis (bronchocentric granulomatosis)
fungal infections
mycobacterial infections