title: Dual anti-neutrophil cytoplasmic antibody-related pauci-immune crescentic glomerulonephritis in a patient with Sjögren's syndrome.
abstract: Sjögren's syndrome is an autoimmune disease that primarily affects exocrine glands. Renal involvement of Sjögren's syndrome may lead to tubulointerstitial disease, whereas secondary glomerulopathies such as anti-neutrophil cytoplasmic antibody (ANCA)-related pauci-immune crescentic glomerulonephritis are rarely observed. In addition, crescent glomerulonephritis that is simultaneously positive for both myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA has never been reported in Sjögren's syndrome. Here, we report a case of pauci-immune crescentic glomerulonephritis exhibiting positivity for both MPO- and PR3-ANCAs in a patient with primary Sjögren's syndrome. A 71-year-old female was hospitalized for cough, blood-tinged sputum, and dyspnea two weeks after diagnosis with Sjögren's syndrome. On admission, serum anti-nuclear antibody, anti-Ro/SS-A antibody, MPO-ANCA, and PR3-ANCA were all positive, and serum blood urea nitrogen and creatinine (Cr) levels were 42.7 and 2.9 mg/dL, respectively. On the seventh day of hospitalization, the patient's serum Cr level was 5.7 mg/dL, indicating rapidly progressive glomerulonephritis. Renal biopsy resulted in the diagnosis of ANCA-related pauci-immune crescentic glomerulonephritis, for which intravenous methylprednisolone (7 mg/kg/day) was administered for three consecutive days, followed by combination therapy with oral prednisolone (1 mg/kg/day) and intravenous cyclophosphamide (500 mg/m(2)). The patient was positive in the Schirmer's I test, and a salivary gland biopsy showed sialadenitis with lympho-plasmacytic infiltrations. On day 28 of hospitalization, the patient was discharged after amelioration of respiratory symptoms and azotemia. At 6 months after discharge, the patient continued to receive appropriate daily medications and was negative for both MPO- and PR3-ANCAs, with a slight elevation in serum Cr levels.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Catholic University of Daegu School of Medicine, 17-Gil 33, Duryugongwon-ro, Nam-gu, Daegu, 42472, Korea. ihlee@cu.ac.kr.
authors.forename: In Hee
authors.identifier: http://orcid.org/0000-0003-3562-7586
authors.initials: IH
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
authors.forename: Seong-Kyu
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Department of Pathology, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Min-Kyung
authors.initials: MK
authors.lastname: Kim
mesh_terms: D000368:Aged; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood* / Q000276:immunology; D003404:Creatinine / Q000097:blood; D005260:Female; D005921:Glomerulonephritis / Q000097:blood / Q000150:complications / Q000276:immunology*; D006801:Humans; D053146:Myeloblastin / Q000276:immunology; D009584:Nitrogen / Q000097:blood; D009195:Peroxidase / Q000276:immunology; D012859:Sjogren's Syndrome / Q000097:blood / Q000150:complications / Q000276:immunology*
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D003404:Creatinine; D009195:Peroxidase; D053146:Myeloblastin; D009584:Nitrogen
keywords: Anti-neutrophil cytoplasmic antibody; Crescentic glomerulonephritis; Rapidly progressive glomerulonephritis; Sjögren’s syndrome