Plasmapheresis Is Associated With Better Renal Outcomes in Lupus Nephritis Patients With Thrombotic Microangiopathy

The aim of this study was to evaluate the efficacy of plasmapheresis in patients with lupus nephritis-combined thrombotic microangiopathy (TMA) in a Chinese cohort.Clinical and therapeutic data of patients with lupus nephritis-combined TMA were collected retrospectively. A comparison between those with and without plasmapheresis was performed.Seventy patients with renal biopsy-proven TMA in lupus nephritis were treated with conventional combined corticosteroid and immunosuppressive agents as induction therapy, 9 of the 70 patients received additional plasmapheresis. The plasmapheresis group presented with more severe SLE and renal activity indices, including a significant higher ratio of neurologic disorder (P = 0.025), lower level of platelet count (P = 0.009), higher value of serum creatinine (P = 0.038), higher percentage of anti-cardiolipin antibodies positive (P = 0.001), and higher Systemic Lupus Erythematosus Disease Activity Index scores (P = 0.012), than that of the nonplasmapheresis group. However, the plasmapheresis group had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.03). As the baseline data were significantly different between the 2 groups, the propensity score match was further designed to avoid retrospective bias. After re-analysis, the plasmapheresis group still had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.018). More importantly, the plasmapheresis group had significant less composite endpoints than that of the nonplasmapheresis group (P = 0.005).Our study suggested that additional plasmapheresis on conventional induction therapy may benefit patients with lupus nephritis-combined TMA, which warrants further explorations.