Effectiveness of renoprotective approaches for persistent proteinuria in lupus nephritis: more than just immunosuppression

Abstract

Objective The objective of this study is to evaluate the efficacy of a tightly controlled renoprotective protocol in systemic lupus erythematosus (SLE) patients with persistent proteinuria. Methods Thirteen SLE patients with nephritis and persistent proteinuria (>1 g/24 hours) were included. The protocol consisted of regular clinical evaluations every two weeks to assess blood pressure (BP, target <130/80 mmHg), adherence to therapy, diet and smoking. No change in immunosuppressive drugs was allowed but reduction of glucocorticoid dose was permitted if indicated. Clinical, laboratory and treatment evaluations were performed at baseline and at the end of the study (after three months). Results SLE patients had a mean age of 37.85 +/- 7.68 years and disease duration of 9.85 +/- 7.29 years. At baseline, patients had a mean duration of maintenance therapy of 10.38 +/- 7.56 months, 12 with mycophenolate mofetil (92.3%) and one with azathioprine (7.7%). At least one dose optimization of antihypertensive regimen was required in all patients during the study. Seven patients (53.8%) had BP>130/80mmHg at baseline. At the end, 11 patients (84.6%) achieved stable BP target; 92.3% were using an angiotensin-converting enzyme inhibitor, 53.9% an angiotensin receptor blocker, and 46.2% were using combined therapy. All patients had a significant reduction in proteinuria levels (2.26 +/- 1.09 vs 0.88 +/- 0.54 g/24 hours, p < 0.001) and 61.5% achieved proteinuria <1 g/24 hours. A significant decrease in mean prednisone dose was observed (10.96 +/- 6.73 vs 5.38 +/- 3.36 mg/day, p = 0.013) as well as mean Systemic Lupus Erythematosus Disease Activity Index score (4.38 +/- 0.72 vs 3.08 +/- 1.86, p = 0.043). No significant changes were identified in serum creatinine, albumin, potassium, complement 3 and complement 4 levels (p > 0.05). Conclusion This study provides evidence that a tightly controlled renoprotective protocol is effective in reducing persistent proteinuria in lupus nephritis. The concomitant reduction of prednisone without any change in immunosuppression reinforces the importance of strategies beyond the treatment of nephritis activity.