Anti-dsDNA, anti-Sm antibodies, and the lupus anticoagulant: significant factors associated with lupus nephritis

Background: Lupus nephritis (LN) is a common manifestation in patients with systemic lupus erythematosus (SLE). Autoantibodies and ethnicity have been associated with LN, but the results are controversial. Objective: To study the immunological and demographic factors associated with the development of LN. Patients and methods: A retrospective case-control study of 127 patients with biopsy-proven LN, and 206 randomly selected patients with SLE without nephritis as controls was designed. All patients had attended our lupus unit during the past 12 years. Standard methods were used for laboratory testing. Results: Patients with LN were significantly younger than the controls at the time of SLE diagnosis (mean (SD) 25.6 (8.8) years v 33.7 (12.5) years;