Remission and long-term outcomes of proliferative lupus nephritis: retrospective study of 96 patients from Saudi Arabia

Background Few data are available about the rate of short-term remission and its impact on the long-term outcomes of proliferative lupus nephritis in the Middle East. Methods An observational study was carried out involving 96 adult patients with biopsy-proven focal or diffuse proliferative lupus nephritis (PLN) from four different hospitals. Data on induction, remission and long-term outcomes were collected and analyzed. Results Among the 96 patients with biopsy-proven PLN (median age 27 (IQR: 21,34) years, 85% women and median duration of systemic lupus erythematosus (SLE) prior to diagnosis 27 (IQR: 11, 55) months), 67% developed remission at 6 months (proportion 0.67; 95% CI 0.57, 0.76). Mycophenolate mofetil (MMF) was used in 45/96 (47%), CYC in 41/95 (43%) and other agents in 10/96 (10%). The choice of MMF as induction agent has increased in recent years. Among baseline characteristics, only histologic activity was found to have a significant association with remission, with active lesions more likely to remit than active/chronic and chronic lesions (AOR 6.5, 95% CI 1.44-29.39, p = 0.015). Based on Kaplan-Meier analysis, the 5-year renal survival rate without doubling serum creatinine was 73.8%. Compared to patients with complete remission, lower long-term renal survival rates were observed in patients with no remission (89.7 versus 43%, p = 0.001) and partial remission (89.7 versus 77.6%, p = 0.256). The cumulative rate of doubling serum creatinine, dialysis, relapse and death was 23%, 11%, 10% and 5%, respectively, at 48-month median follow up. Conclusion Approximately two-thirds of patients with PLN develop remission in response to standard induction therapy. Remission was negatively associated with the presence of chronic changes in renal biopsy. Overall, MMF is the most commonly used agent to induce remission; however, with more severe disease CYC, is used more frequently. PLN is associated with significant long-term renal outcomes including a 26% cumulative rate of doubling of serum creatinine at 5 years. Initial remission predicts this long-term renal survival.