Kidney Transplantation in Patients With AA Amyloidosis: Outcomes in a French Multicenter Cohort

Rationale & Objective: Outcomes of kidney transplantation for patients with renal AA amyloidosis are uncertain, with reports of poor survival and high rates of disease recurrence. However, the data are inconclusive and mostly based on studies from the early 2000s and earlier. Study Design: Retrospective multicenter cohort study. Setting & Participants: We searched the French national transplant database to identify all patients with renal AA amyloidosis who underwent kidney transplantation between 2008 and 2018. Exposures: Age, cause of amyloidosis, use of biotherapies, and C-reactive protein levels. Outcomes: Outcomes were all-cause mortality and allograft loss. We also reported amyloidosis allograft recurrence, occurrence of acute rejection episodes, as well as infectious, cardiovascular, and neoplastic disease events. Analytical Approach: Kaplan-Meier estimator for mortality and cumulative incidence function method for allograft loss. Factors associated with patient and allograft survival were investigated using a Cox proportional hazards model and a cause-specific hazards model, respectively. Results: 86 patients who received kidney transplants for AA amyloidosis at 26 French centers were included. The median age was 49.4 years (IQR, 39.7-61.1). The main cause of amyloidosis was familial Mediterranean fever (37 cases; 43%). 16 (18.6%) patients received biotherapy after transplantation. Patient survival rates were 94.0% (95% CI, 89.1-9 9.2) at 1 year and 85.5% (77.8-9 4.0) at 5 years after transplantation. Cumulative incidences of allograft loss were 10.5% (4.0-17.0) at 1 year and 13.0% (5.8-20.1) at 5 years after transplantation. Histologically proven AA amyloidosis recurrence occurred in 5 transplants (5.8%). An infection requiring hospit alization developed in 55.8% of cases, and there was a 27.9% incidence of acute allograft rejection. Multivariable analysis showed that C-reactive protein concentration at the time of transplant ation was associated with patient survival (HR, 1.01; 95% CI, 1.00-1.02; P = 0.01) and allograft survival (HR, 1.68; 95% CI, 1.10-2.57; P = 0.02). Limitations: The study lacked a control group, and the effect of biotherapies on transplantation outcomes could not be explored. Conclusions: This relatively contemporary cohort of patients who received a kidney transplant for AA amyloidosis experienced favorable rates of survival and lower recurrence rates than previously reported. These data support the practice of treating these patients with kidney transplant ation for end -stage kidney disease.