PURPOSE:Renal disease is the major cause of mortality and morbidity in systemic lupus erythematosus. The aim of this study was to examine the therapeutic outcome of patients with lupus nephritis (LN) for 21 years. METHODS:We conducted a retrospective study of 100 patients with biopsy proven LN who were admitted at Keimyung University Dongsan Hospital between 1985 and 2006, and were followed with a mean of 73 months. We diagnosed renal pathology according to WHO 1995 classification, and analyzed the therapeutic and long-term outcome of patients with LN treated with steroid alone or steroid with intravenous cyclophosphamide (CYC). RESULTS:The mean age at the time of renal biopsy was 28. 3 years and male to female ratio was 1:9.9. The initial therapy consisted of steroid alone in 69 patients and steroid with intravenous CYC in 31 patients. The proportion of diffuse proliferative LN and titer of anti ds-DNA were significantly higher in patients treated with steroid and CYC than in patients with steroid alone. The percentage of patients with clinical response was significantly higher in patients with steroid and CYC than in patients with steroid alone (p=0.018). The patients who experienced clinical response had an excellent long term outcome compared with those who had no clinical response. CONCLUSION:The clinical response was significantly higher in CYC combination regimen than steroid alone. The response to therapy in LN was an important factor for long-term prognosis. The early diagnosis and aggressive treatment with immunosupppressive agents are valuable for better outcome in patient with LN.