MPO-C-ANCA Renal-Limited Vasculitis: A Puzzling Phenomenon

John Michael Bowling, Jesselyn Anne Jozwiak, Mark Lincoln Bunker


Antineutrophil cytoplasmic antibodies (ANCAs) are autoantibodies directed against antigens in the cytoplasm of neutrophils and can be used diagnostically to identify different types of systemic vasculitides such as microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA), and renal-limited vasculitis (RLV). Two methods are used concomitantly to detect ANCAs: indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA). IIF yields either a cytoplasmic (C-ANCA) or peri-nuclear (P-ANCA) pattern with a corresponding antigen identified on ELISA; either proteinase-3 (PR-3) or myeloperoxidase (MPO), respectively. Here, we present a 76 year-old female with a presenting complaint of nausea and emesis, ultimately found to have renal-limited MPO-C-ANCA vasculitis, an unusual IIF and ELISA pairing. The patient presented with lower extremity edema and without nasopharyngeal or pulmonary involvement, complicating the clinical picture for an ANCA-vasculitis. Given other published reports and studies pertaining to this unique finding of C-ANCA with anti-MPO antibodies, we emphasize the importance of using caution while interpreting ANCA results. The diagnosis of vasculitis should be comprehensive and should not solely rely on IIF or physical exam findings. 

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Hauer HA, Bajema IM, Van Houwelingen HC, et al. Renal histology in ANCA-associated vasculitis: Differences between diagnostic and serologic subgroups. Kidney International. 2002;61(1):80-89. doi:10.1046/j.1523-1755.2002.00089.x


Chhabra S, Minz R, Goyal L, Sharma N. Myeloperoxidase-antineutrophil Cytoplasmic Antibodies with Cytoplasmic Fluorescence Pattern. Journal of Laboratory Physicians. 2010;2(1):42. doi:10.4103/0974-2727.66707

Parmar MS, Bashir K. Crescentic Glomerulonephritis. [Updated 2019 Mar 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available from:

Koratala A, Wakefield DN, Alquadan KF, Ahsan Ejaz A. MPO-C-ANCA-associated necrotising and crescentic glomerulonephritis. JRSM Open. 2017;8(4):205427041769271. doi:10.1177/2054270417692710


Lim G, Lim S, Tee S-I, Ling CY. A challenging diagnosis of MPO-C-ANCA EGPA. BMJ Case Reports. 2019;12(7):e228621. doi:10.1136/bcr-2018-228621

Segelmark M, Baslund B, Wieslander J. Some patients with anti-myeloperoxidase autoantibodies have a C-ANCA pattern. Clinical and experimental immunology. 1994;96(3):458-465. doi:10.1111/j.1365-2249.1994.tb06051.x

?7. Hirai Y, Iyoda M, Shibata T, et al. Lupus nephritis associated with positive MPO-ANCA in a patient with underlying autoimmune hemolytic anemia. Clinical and Experimental Nephrology. 2008;12(5):393-397. doi:10.1007/s10157-008-0058-1


Lane SK, Joseph W. Gravel J. Clinical Utility of Common Serum Rheumatologic Tests. American Family Physician. 2002;65(6):1073.

Bossuyt X, Cohen Tervaert J-W, Arimura Y, et al. Revised 2017 international consensus on testing of ANCAs in granulomatosis with polyangiitis and microscopic polyangiitis. Nature Reviews Rheumatology. 2017;13(11):683-692. doi:10.1038/nrrheum.2017.140




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ISSN: 2333-4096