title: Clinical implications of antineutrophil cytoplasmic antibody test in lupus nephritis.
abstract: To elucidate the prevalence and clinical implications of antineutrophil cytoplasmic antibody (ANCA) in lupus nephritis (LN), we examined ANCA by indirect immunofluorescence and by ELISA against antilactoferrin (anti-LF) and antimyeloperoxidase (anti-MPO) antibody. To discriminate perinuclear ANCA (pANCA) with antinuclear antibody (ANA), all the ANCA-positive sera were tested again after incubating patients' sera with single-stranded (SS) and double-stranded (ds) DNA. These results were compared with clinicopathologic manifestations and clinical courses of LN. ANCA was positive in 19 (37.3%) of 51 LN patients. Among these LN patients, 3 had cytoplasmic ANCA (cANCA) and 16 had pANCA. ANCA was not found in 8 SLE patients without nephritis and 30 normal controls. The presence of ANCA, particularly pANCA, was associated with the presence of nephritis (18/51 cases vs. 0/8 cases, p < 0.05), especially with diffuse proliferative lupus nephritis, WHO class IV (17/18 cases vs. 21/31 cases, p < 0.05) as well as the presence of anti-dsDNA antibody (17/19 cases vs. 18/30 cases, p < 0.05). Patients with ANCA frequently had deterioration of renal function (3/16 vs. 0/26 cases). Anti-LF antibody was positive in 13 patients. Among those, 12 patients had nephritis. Five patients with anti-LF antibody did not have ANCA, but 7 had pANCA, and 1 had cANCA. Patients with anti-LF antibody had lower initial creatinine levels than those without it [serum creatinine (mg/dl): 0.78 (0.6-1.0) vs. 1.43 (0.5-5.0), p < 0.05]. Anti-MPO antibody was positive in only 1 patient, suggesting that MPO is a rare antigen for ANCA in LN.
authors.affiliation: Division of Nephrology, College of Medicine, Seoul National University, Seoul, South Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Chin
authors.forename: C
authors.initials: C
authors.lastname: Ahn
authors.forename: C S
authors.initials: CS
authors.lastname: Lim
authors.forename: H K
authors.initials: HK
authors.lastname: Chung
authors.forename: J G
authors.initials: JG
authors.lastname: Lee
authors.forename: Y W
authors.initials: YW
authors.lastname: Song
authors.forename: H S
authors.initials: HS
authors.lastname: Lee
authors.forename: J S
authors.initials: JS
authors.lastname: Han
authors.forename: S
authors.initials: S
authors.lastname: Kim
authors.forename: J S
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000032:analysis*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007781:Lactoferrin / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis; D008181:Lupus Nephritis / Q000175:diagnosis* / Q000276:immunology; D008297:Male; D009195:Peroxidase / Q000276:immunology
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D009195:Peroxidase; D007781:Lactoferrin