Résumé
<b>Rationale & Objective:</b> Outcomes of kidney transplantation for patients with renal AA amyloidosis are uncertain, with reports of poor survival and high rates of disease recurrence. However, data are inconclusive and mostly based on studies from the early 2000s and earlier.<br /><b>Study Design:</b> Retrospective multicenter cohort study.<br /><b>Setting & Participants:</b> We searched the French national transplant database to identify all patients with renal AA amyloidosis who underwent kidney transplantation between 2008 and 2018.<br /><b>Exposures:</b> Age, cause of amyloidosis, use of biotherapies, CRP levels.<br /><b>Outcomes:</b> 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.<br /><b>Analytical Approach:</b> The Kaplan-Meier estimator for mortality and the 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.<br /><b>Results:</b> Eighty-six patients who received kidney transplants for AA amyloidosis at 26 French centers were included. The median age was 49.4 years (interquartile range 39.7-61.1). The main cause of amyloidosis was Familial Mediterranean Fever (37 cases, 43%). Sixteen (18.6%) patients received a biotherapy after transplantation. Patient survival was 94.0% (95% confidence interval 89.1-99.2) at 1 year and 85.5% (77.8-94.0) at 5 years post-transplantation. The cumulative incidence of allograft loss was 10.5% (4.0-17.0) at 1 year, and 13.0% (5.8-20.1) at 5 years post-transplantation. Histologically proven AA amyloidosis recurrence occurred in 5 transplants (5.8%). 55.8% of cases developed an infection requiring hospitalization and 27.9% acute allograft rejection. Multivariable analysis showed that CRP concentration at the time of transplantation was associated with patient survival (HR 1.01, 95% CI 1.00-1.02, p=0.01) and with allograft survival (HR 1.68, 95% CI 1.10-2.57, p 0.02).<br /><b>Limitations:</b> The study lacked a control group and the effect of biotherapies on transplantation outcomes could not be explored.<br /><b>Conclusions:</b> 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 transplantation for end-stage kidney disease.<br/><b>Plain-Language Summary</b><br/>AA amyloidosis is a severe and rare disease. Kidney involvement is frequent and leads to end-stage kidney disease. Because of the involvement of other organs, these patients are often frail, which has raised concerns about their suitability for kidney transplantation. We reviewed all patients with AA amyloidosis nephropathy who underwent kidney transplantation in France in the recent era (2008-2018) and found that the outcomes after kidney transplantation were favorable, with 85.5% of patients still alive 5 years after transplantation, a survival rate that is comparable to the outcomes of patients receiving a transplant for other forms of kidney diseases. Recurrence of amyloidosis in the transplanted kidney was infrequent (5.8%). These data support the practice of kidney transplantation for patients with AA amyloidosis who experience kidney failure.