Recovery of renal function in patients with lupus nephritis and reduced renal function: the beneficial effect of hydroxychloroquine

Background Reduced renal function is associated with worse renal outcome in patients with lupus nephritis (LN). However, there is insufficient knowledge regarding renal function recovery in patients with LN with reduced baseline renal function. Therefore, the present study aimed to investigate renal function recovery and related factors in patients with reduced baseline renal function. Methods The present retrospective longitudinal cohort study included patients with LN and reduced renal function. Reduced renal function was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m 2 . Recovery of renal function was determined by an eGFR of >60 mL/min/1.73 m 2 at six months after baseline, and factors associated with it were evaluated using logistic regression analysis. Results We included 90 patients with LN, with a mean eGFR value of 37.2 ± 13.9 mL/min/1.73 m 2 . Forty-six (51.1%) patients recovered their renal function after six months. On multivariate analysis, hydroxychloroquine use (odds ratio (OR) = 3.891, 95% confidence interval (CI) 1.196–12.653, p = 0.024), prolonged LN (OR = 0.926, 95% CI 0.874–0.981, p = 0.009) and high-grade tubular atrophy (OR = 0.451, 95% CI 0.208–0.829, p = 0.013) were associated with renal function recovery. During follow up, 25 patients were on end-stage renal disease (ESRD). Kaplan–Meier analysis revealed that renal function recovery after six months and lower probability of ESRD are associated. Conclusions In patients with LN and reduced renal function, renal function recovery at six months was associated with use of hydroxychloroquine and inversely related to longer duration of LN and higher grade of tubular atrophy.