Author/Editor		Vizjak, Alenka; Rott, Tomaž; Koselj-Kajtna, Mira; Rozman, Blaž; Kaplan-Pavlovčič, Staša; Ferluga, Dušan
Title		Histologic and immunohistologic study and clinical presentation of ANCA-associated glomerulonephritis with correlation to ANCA antigen specificity
Type		članek
Source		Am J Kidney Dis
Vol. and No.		Letnik 41, št. 3
Publication year		2003
Volume		str. 539-49
Language		eng
Abstract		Background: The major antigen specificities of antineutrophil cytoplasmfc antibodies (ANCA) are for proteinase 3 (PR3) and myeloperoxidase (MPO). Only a limited number of studles have systematlcally assessed renal pathology with respect to ANCA antigen specificity. Methods: The authors evaluated renal biopsy light microscopy and immunofluorescence findings, clinical presentation, and outcome In 135 patients with ANCAassociated vasculitides. Results: Patients were divided into 3 groups: PR3-ANCA (n = 55), MPO-ANCA (n = 74), and ANCA of other specificities (n = 6). The mean duration of renal disease at biopsy was significantly longer in patients with MPO-ANCA than in those with PR3-ANCA (6.9 v 3.0 months). Immunofluorescence results showed mostly pauci-immune glomerulonephritis (n = 129) and rarely diffuse granular glomerular immune deposits suggesting immune complex deposition (n = 6). A focal form of crescentic glomerulonephritis was more frequent (P < 0.001), and glomerular necrosis was more prominent (P = 0.013) in the PR3-ANCA group, whereas diffuse crescentic glomerulonephritis, glomerulosclerosis, and interstitial fibrosis predominated in the MPO-ANCA group (P < 0.001). Extraglomerular vasculitis, present in 22.2%, and chronic vascular leslons Indicative of previous vasculitis, present in 11.9% of patients, correlated with systemic involvement. Concluslon: The evolution of the pathologic lesions of PR3-ANCA and MPO-ANCA-associated glomerutonephritis seems to be similar. Differences in histopathology could be explained by the observation that in patients with PR3-ANCA, kidney biopsy was performed soon after renal invotvement appeared, and focal active lesions were prevalent, whereas in patients with MPO-ANCA, kidney biopsy was done late in the course of the disease, and diffuse chronic sclerotic lesions predominated. Renai extraglomerular small vessel vasculitis appeared to be predictive of systemic involvement.
Descriptors		VASCULITIS GLOMERULONEPHRITIS ANTIBODIES, ANTINEUTROPHIL CYTOPLASMIC ANTIGEN-ANTIBODY COMPLEX GLOMERULOSCLEROSIS, FOCAL IMMUNOHISTOCHEMISTRY FLUOROIMMUNOASSAY TREATMENT OUTCOME