Immunofluorescence pattern produced by binding of ANCA to ethanol-fixed neutrophils, from a person with<unk> <unk>  is usually suspected only when a person has had unexplained symptoms for a long period of time. Determination of anti-neutrophil cytoplasmic antibodies (ANCAs) can aid in the diagnosis, but positivity is not conclusive and negative ANCAs are not sufficient to reject the diagnosis. More than 90% of people who have<unk>  test positive for ANCA. Cytoplasmic-staining ANCAs that react with the enzyme proteinase 3 (cANCA) in neutrophils (a type of white blood cell) are associated with<unk> . Involvement of the ears, nose, and throat is more common in<unk>  than in the similar condition microscopic polyangiitis. If the person has signs of kidney involvement or cutaneous vasculitis, a biopsy is obtained from the kidneys. On rare occasions, thoracoscopic lung biopsy is required. On histopathological examination, a biopsy will show leukocytoclastic vasculitis with necrotic changes and granulomatous inflammation (clumps of typically arranged white blood cells) on microscopy. These granulomas are the main reason for the name<unk> , although it is not an essential feature. Nevertheless, necrotizing granulomas are a hallmark of this disease. However, many biopsies can be nonspecific and 50% provide too little information for the diagnosis of<unk> . Classification<unk>  is part of a larger group of vasculitic syndromes called systemic vasculitides or necrotizing vasculopathies, all of which feature an autoimmune attack by an abnormal type of circulating antibody termed ANCAs (antineutrophil cytoplasmic antibodies) against small and medium-size blood vessels. Apart from<unk> , this category includes eosinophilic<unk>  (EGPA) and microscopic polyangiitis. Although<unk>  affects small- and medium-size vessels, it is formally classified as one of the small vessel vasculitides in the Chapel Hill system. Criteria In 1990, the American College of Rheumatology accepted classification criteria for<unk> . These criteria were not intended for diagnosis, but for inclusion in randomized controlled trials. Two or more positive criteria have a sensitivity of 88.2% and a specificity of 92.0% of describing<unk> . The left apical region is opacified in a case of<unk> . * Nasal or oral inflammation: * painful or painless oral ulcers or * purulent or bloody nasal discharge * Lungs: abnormal chest X-ray with: * nodules, * infiltrates or * cavities * Kidneys: urinary sediment with: * microscopic hematuria or * red cell casts * Biopsy: granulomatous inflammation * Photo showing the sclerokeratitis associated with<unk> within the arterial wall or * in the perivascular area According to the Chapel Hill Consensus Conference (CHCC) on the nomenclature of systemic vasculitis (1992), establishing the diagnosis of<unk>  demands: * a granulomatous inflammation involving the respiratory tract, and * a vasculitis of small to medium-size vessels. Several investigators have compared the ACR and Chapel Hill criteria.
Granulomatosis with polyangiitis
Microscopic polyangiitis
Polyarteritis nodosa
Thromboangiitis obliterans
Eosinophilic granulomatosis with polyangiitis
Lupus vasculitis
Nephrogenic systemic fibrosis
Transplant glomerulopathy