Microscopic description:

Acute necrotizing fibrinoid vasculitis

Granulation tissue

Giant cells

Acute inflammation


Systemic necrotizing vasculitis that typically involves kidneys, lung, upper aerodigestive tract.

Otologic involvement (otitis media, tympanic membrane perforation, sensorineural hearing loss, perforation of ear lobes, external otitis) as well as facial palsy occurs in 20 - 60% who have disease at traditional sites.

Vasculitis, necrosis or granulomatous inflammation (few cases have all 3).

Name changed in 2011. Was earlier called Wegener’s granulomatosis (which is a clinical diagnosis).

Triad of necrotizing angiitis, aseptic necrosis of upper respiratory tract and lungs and focal glomerulonephritis.

Likely a T cell mediated hypersensitivity reaction, the close relationship between c-ANCA titers suggests a pathogenic role.

c-ANCA likely directly activates neutrophils to release oxygen radicals and proteolytic enzymes damaging endothelium.

c-ANCA positive in 90% with active generalized disease and 60% with limited disease.

c-ANCA positive: diffuse cytoplasmic staining directed against neutrophil serine proteinase 3; can monitor course of disease with titers, ELISA test for anti-proteinase 3 now available.

p-ANCA: perinuclear staining, directed against myeloperoxidase, is usually negative, but positive in microscopic polyarteritis, inflammatory bowel disease, crescentic glomerulonephritis; ELISA test for anti-myeloperoxidase now available.


Falk RJ, Gross WL, Guillevin L, Hoffman G, Jayne DR, Jennette JC, Kallenberg CG, Luqmani R, Mahr AD, Matteson EL, Merkel PA, Specks U, Watts R. Granulomatosis with polyangiitis (Wegener's): an alternative name for Wegener's granulomatosis. J Am Soc Nephrol. 2011 Apr;22(4):587-8. doi: 10.1681/ASN.2011010081. Epub 2011 Mar 3. PMID: 21372208.

Raynaud P, Garrel R, Rigau V, Poizat F, Vic P, Cartier C, Rivière S, Baldet P, Costes V. Comment améliorer la rentabilité diagnostique des biopsies de la sphère oto-rhino-laryngée dans la maladie de Wegener: analyse anatomo-clinique de 49 biopsies chez 21 patients [How can the diagnostic value of head and neck biopsies be increased in Wegener's granulomatosis: a clinicopathologic study of 49 biopsies in 21 patients]. Ann Pathol. 2005 Apr;25(2):87-93. French. doi: 10.1016/s0242-6498(05)86171-1. PMID: 16142159.