Outcome of childhood lupus nephritis in Saudi children

Abstract

Our aim in this study is to report the long-term renal outcome of a cohort of Saudi children with systemic lupus erythematosus (SLE). All patients with childhood lupus nephritis (cLN) proved by renal biopsy seen between January 2000 and June 2015 were reviewed. The renal outcome was assessed according to serum creatinine level, protein/creatinine ratio at the last follow-up visit, and/or evidence of renal impairment during follow-up period and end-stage renal disease (ESRD). Additional outcome measures include accrual damage measured by pediatric adaptation of the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (pSDI), and death related to SLE was determined. A total of 84 (72 females) cLN patients with follow-up duration of 9.3 years (±5.2) were included in this study. The mean current age was 19.4 years (±5.5) and mean age at onset was 9.2 years (±2.4). The most frequent histopathological class was proliferative glomerulonephritis (64.3%) followed by membranous nephritis (27.4%). The mean activity and chronicity indices were 5.9 (±3.9) and 2.9 (±2.2), respectively. Renal microthrombosis was found in 9 (10.7%) patients. All patients treated with immunosuppressive medications; cyclophosphamide used in 64 followed by mycophenolate mofetil in 42, then azathioprine in 19 patients, while rituximab used in 24 patients. At the last follow-up visit, the mean serum creatinine was 147 umol/L (±197) and the mean protein/ creatinine ratio was 0.8 (± 1.1) while the mean total pSDI was 1.9 (±1.9) and mean renal SDI was 0.7 (±1.1). Sixteen (19%) patients had ESRD and eight of them had class IV nephritis. However, there was no significant difference in ESRD by histological class. The overall survival rates were five years: 94% and 10 years: 87%. Infection was the leading cause of mortality. Our patients had severe cLN and required intensive treatment. Despite the survival rate is comparable to other studies, ESRD is more frequent and this may be attributed to genetic or ethnic factors.