Autoantibodies in lupus nephritis useful in distinguishing proliferative nephritis from membranous nephritis

Abstract

Objectives: This study was conducted to determine autoantibodies associated with lupus nephritis, especially those useful in diagnosing proliferative and membranous nephritis. Methods: 106 patients with lupus nephritis and 63 patients with SLE but no nephritis were enrolled. 55 patients were selected from the lupus nephritis group and were divided into two groups: proliferative nephritis patients (n=36) and membranous nephritis patients (n=19). The autoantibody profiles of patients’ sera were evaluated using the EUROLINE ANA profile 3 (IgG) kit. Results: A higher positivity rate of anti-dsDNA antibody and anti-histone antibody were seen in lupus nephritis patients compared to non-renal SLE patients. In comparing between proliferative and membranous nephritis, positivity of anti-nucleosome antibody was higher in proliferative nephritis compared to membranous nephritis, although it was not statistically significant. However, anti-nucleosome antibody-positive patients with lupus nephritis had higher prevalence of hematuria and pyuria, which are strong indications of proliferative nephritis. Also, a significantly higher positivity rate of anti-RNP70 antibody was seen in membranous nephritis compared to proliferative nephritis. Conclusions: Our results showed anti-nucleosome antibody and anti-RNP70 antibodies may be predictive non-histological factors for discriminating between proliferative and membranous lupus nephritis.