Lupus flare and recurrent lupus nephritis following kidney transplantation in patients with lupus nephritis

Background Clinical manifestations and risk factors associated with systemic lupus erythematosus (SLE) flares, including recurrent lupus nephritis (LN), in patients with LN who undergo kidney transplantation have been unclear. Methods Kidney transplant recipients with LN from January 1995 to December 2021 were included in this study. A disease flare was defined as either an increase in the non‐renal SLE disease activity index score or the presence of biopsy‐proven recurrent LN. Results Among a total of 93 patients with LN who underwent kidney transplantation, 11 patients (11.8%) experienced SLE flares during a median follow‐up period of 76.9 months (IQR, 43.0–122.4). The most common clinical manifestations of SLE flares were recurrent LN (4/11, 36.4%) and hematologic manifestations (4/11, 36.4%). Patients who had flares had significantly higher anti‐double‐stranded DNA (anti‐dsDNA) antibody titers both before and after transplantation. Furthermore, an increased anti‐dsDNA antibody level before transplantation was associated with a high risk of an SLE flare (HR, 1.030; p = .008). Conversely, preemptive transplantation was associated with a lower risk of a flare (HR, 0.617; p = .026). The rate of patient death‐censored graft survival was found to be considerably lower in patients with recurrent LN than in those without LN. Conclusions Approximately 10% of patients with LN experienced an SLE flare after transplantation, with recurrent LN being the most frequent manifestation. Anti‐dsDNA antibody titers before transplantation were significantly related to the risk of an SLE flare. Notably, preemptive transplantation was associated with a reduced risk of flares following transplantation.