Sustained remission of lupus nephritis

Abstract

The aim of this study was to describe the clinical course of patients with lupus nephritis (LN) who attain a sustained remission (SR) and identify predictors of SR. A retrospective study of patients with biopsy-proven LN were followed for up to 10 years. SR was defined as normal renal function, urine protein <0.5 g/day, and an inactive urine sediment without significant immunosuppressive maintenance therapy for no less than three years. Control patients had LN but did not fulfill the criteria for SR. Data was collected at diagnosis of LN (T0), at onset of remission (T1), and at final follow-up (T2). A total of 35 patients were identified, 16 with a SR of LN and 19 controls, with a mean ± SD follow-up of 126.4 ± 8.5 months. Remission of LN was achieved following 37.7 ± 6.8 months of therapy. At diagnosis (T0) the WHO classification of nephritis, activity and chronicity scores of renal biopsies were comparable in the two groups. At final follow-up (T2), the mean estimated creatinine clearance for the SR group was significantly higher than in controls ( P = 0.009) and disease activity (SLEDAI scores) was lower ( P = 0.002). Cumulative damage (SDI scores) in the SR group did not increase after patients entered remission ( P = 0.250), whereas the mean SDI score in the control group increased significantly ( P = 0.014) even when renal variables were excluded ( P = 0.016). Multivariate analysis revealed that female gender ( P = 0.023), older age ( P = 0.034), higher non-renal SLEDAI scores ( P = 0.016) at the time of diagnosis of LN and absence of azathioprine ( P = 0.010) were predictive of SR. It was concluded that remission of LN occurs in a substantial proportion of systemic lupus erythematosus (SLE) patients and may be sustained without maintenance immunosuppressive therapy. It is associated with a significantly slower accrual of both renal and non-renal damage over the ensuing seven years.