Predictive risk factors for failure to induction therapy of lupus nephritis in a cohort of Colombian patients

Abstract

Objectives: To determine the predictors of failure to obtain remission after induction therapy for proliferative lupus nephritis in a group of northwestern Colombian patients.

Material and methods: A retrospective study was conducted. We included patients with systemic lupus erythematosus according to the American College of Rheumatology criteria who had nephritis confirmed by renal biopsy.

Results: We followed 84 patients: 88.1% female, and 11.9% male. The mean age at diagnosis of systemic lupus erythematosus was 27.5±11.8 years (9-70). The average time between diagnosis of systemic lupus erythematosus and proliferative nephritis onset was 13.6 months (0-168). Histopathologic type: iv (78.57%), iii (15.47%), iii-iv/v (5.96%). Activity index: 6.7±4.6. Chronicity index: 2±2.7. 24-hour proteinuria (mg): 6,164 (130-18,100). Baseline creatinine: 1.14 mg/dL (0.43-7.4). Induction therapy: Steroids (100%), cyclophosphamide (76.2%) and mycophenolate mofetil (23.8%). At six months, 56% of individuals failed to achieve partial or complete remission. Predictors of failure to induction therapy were, in accordance with the bivariate analysis (OR; 95%CI): creatinine level more than 1.2mg/dL (10.8; 3.18-36.84; P<.005), nephrotic range proteinuria (11.9; 3.09-45.8; P<.001), and an activity index above 8 (5.04; 1.7-14.3; P<.001). In the multivariate analysis, only baseline creatinine higher than 1.2mg/dL (10.92; 2.65-45.02; P=.001), and nephrotic range proteinuria (9.81; 1.85-52.04; P=.007) were significant.

Conclusions: A significant percentage of Colombian patients fail to achieve remission of proliferative lupus nephritis after six months of treatment.

Keywords: Inducción de remisión; Lupus nephritis; Nefritis lúpica; Nephrotic syndrome; Remission induction; Síndrome nefrótico.