Lupus nephritis in Indigenous Australians: a single-centre study

Background: The incidence, presentation and outcomes of lupus nephritis (LN) vary with geography, ethnicity, socioeconomic status and gender. There are relatively few data on LN in the non-Caucasian populations in Australia. Aims: To describe the clinical presentation, histological features, natural history, and outcomes of a historical cohort of Aboriginal and Torres Strait Islanders people in Far North Queensland with biopsy-proven LN. Methods: This is a retrospective observational study, and the study was conducted in Cairns and Hinterland Hospital and Health Service, Queensland, Australia. The study included Aboriginal and Torres Strait Islander patients with biopsy-proven LN treated between 1990 and 2013. The main outcome measures were renal replacement therapy and overall patient survival. Results: Aboriginal and Torres Strait Islander people represented a substantial proportion (n = 16/40, 40%) of all patients diagnosed with LN during the observation period. The frequency of nephrotic range proteinuria (n = 11/14, 78.5%), estimated glomerular filtration rate <60 mL/min/1.73 m(2) (n = 6/14, 42.8%) and proliferative LN (n = 13/16, 81.25%) was high at the time of presentation. Despite use of multiple immunosuppressive agents, the overall rate of remission was poor (n = 4/14, 28.5%) and incidence of end-stage kidney disease (n = 4/14, 28.5%) and death (n = 5/16, 31.25%) was high. Conclusions: The clinical presentation of LN in Aboriginal and Torres Strait Islanders in Far North Queensland is severe and the response to standard immunosuppressive therapy is unsatisfactory. Larger prospective multi-centre studies are required to better understand ethnic disparities in prognosis and response to immunosuppressive therapy in this specific population.