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.

Neutrophil extracellular traps mediate transfer of cytoplasmic neutrophil antigens to myeloid dendritic cells toward ANCA induction and associated autoimmunity

“…A minority of SLE patients has been reported to develop ANCA (mainly MPO-ANCAs) but, differently from SVV, the pathogenic role of these autoantibodies in SLE is not clear. Contrasting works have reported the presence 28 or the absence 29,30 of correlation between serum ANCA levels and disease activity in SLE. In a large cohort of SLE patients, serum ANCA levels were found to be correlated with specific clinical manifestations, such as serositis, livedo reticularis, and arthritis.…”

Necrotizing and Crescentic Lupus Nephritis with Antineutrophil Cytoplasmic Antibody Seropositivity

“…The target antigen by ELISA was LF-ANCA in 25% of patients and MPO-ANCA in 2%. ANCA seropositivity was associated with the presence of nephritis, particularly LN IV, as well as anti-dsDNA antibodies (17). Other reports have failed to show a correlation between ANCA and clinical features or organ involvement (14,18,19).…”

Diffuse alveolar hemorrhage in lupus nephritis complicated by microscopic polyangiitis

“…Some reports show no correlation between organ involvement and the presence of MPO-ANCA [6,7]. On the other hand, it has been reported that MPO-ANCA positivity is associated with specific clinical manifestations of SLE such as serositis [8] and nephritis, particularly lupus nephritis class IV [9,10]. Pan et al [11] examined ANCA positivity in new-onset SLE and reported that ANCApositive lupus patients had a higher incidence of nephritis as well as myocarditis, nerves system disorder and serositis.…”