BASELINE PREDICTORS OF RENAL OUTCOME AFTER IMMUNOSUPPRESSIVE THERAPY IN PATIENTS WITH PROLIFERATIVE LUPUS NEPHRITIS

Background: The disease course of lupus nephritis (LN) is highly variable. Identifying prognostic factors for outcome after immunosuppressive therapy is important for optimizing treatment strategies in individual patients. Objectives: To evaluate the predictive value of clinical and biopsy parameters at baseline with regard to renal outcome after immunosuppressive therapy in proliferative LN patients of the first Dutch LN Study. Methods: 87 SLE patients with proliferative LN (86% female, 76% Caucasian) were randomly assigned to either intravenous cyclophosphamide (CY) combined with oral prednisone (OP) (CY group; n=50) or azathioprine (AZA) combined with intravenous methylprednisolone (MP) and OP (AZA/MP group; n=37). After 2 years, both groups were switched to AZA combined with OP. Serum creatinine, proteinuria, anti-dsDNA, and complement C3 and C4 were recorded regularly. Renal biopsy samples, obtained at baseline, were scored according to a standardized method. Predictor analyses for time to occurrence of sustained doubling of serum creatinine and primary treatment failure or relapse were performed using forward conditional Cox regression. Predictor analyses for serum creatinine and proteinuria at last visit were performed using stepwise linear regression. Results: After a median follow-up of 9.6 years (range 0.1-13.2), 11% of patients reached sustained doubling of serum creatinine (CY: 8%; AZA/MP: 16%) and 23% of patients had primary treatment failure (n=1) or renal relapse (n=19) (CY: 10%; AZA/MP: 41%). Non-Caucasian ethnicity was the only independent predictor of time to occurrence of sustained doubling of serum creatinine. Induction therapy with AZA/MP was the only independent predictor of time to occurrence of primary treatment failure or relapse. Median serum creatinine and proteinuria at last visit were 83 μmol/l (range 45-900) and 0.22 g/day (range 0.00-9.42), respectively. Male gender, non-Caucasian ethnicity, older age at baseline, and higher serum creatinine at baseline were predictive for serum creatinine at last visit. Non-Caucasian ethnicity and higher percentage of completely sclerosed glomeruli at baseline were predictive for proteinuria at last visit. Conclusions: Non-Caucasian ethnicity, induction therapy with AZA/MP, male gender, older age, higher serum creatinine, and higher percentage of completely sclerosed glomeruli were identified as independent baseline predictors of worse renal outcome after immunosuppressive therapy. Disclosure of Interest: None DeclaredCitation: Annals of the Rheumatic Diseases, volume 70, supplement 3, year 2011, page 323Session: SLE, Sjögren's and APS – treatment (Poster Presentations )