Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA.
General Clinical Research Center, Clinical & Translational Science Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA.
Kidney Int. 2023 Jan;103(1):187-195. doi: 10.1016/j.kint.2022.09.030. Epub 2022 Nov 1.
Antibody-mediated rejection (AMR) is the major cause of graft loss in kidney transplant recipients. The Banff classification defines two classes of AMR, active and chronic active but over time this classification has become increasingly complex. To simplify the approach to AMR, we developed activity and chronicity indices based on kidney transplant biopsy findings and examined their association with graft survival in 147 patients with active or chronic active AMR, all of whom had donor-specific antibodies and were treated for AMR. The activity index was determined as the sum of Banff glomerulitis (g), peritubular capillaritis (ptc), arteritis (v) and C4d scores, with a maximum score of 12. The chronicity index was the sum of interstitial fibrosis (ci), tubular atrophy (ct), chronic vasculopathy (cv), and chronic glomerulopathy (cg) scores, the latter doubled, with a maximum score of 15. While the activity index was generally not associated with graft loss, the chronicity index was significantly associated with graft loss with an optimal threshold value of 4 or greater for predicting graft loss. The association of the chronicity index of 4 or greater with graft loss was independent of other parameters associated with graft loss, including the estimated glomerular filtration rate at the time of biopsy, chronic active (versus active) AMR, AMR with de novo (versus persistent/rebound) donor-specific antibodies, Banff (g+ptc) scores, concurrent T cell-mediated rejection and donor-specific antibody reduction post-biopsy. The association of the chronicity index of 4 or greater with graft loss was confirmed in an independent cohort of 61 patients from Necker Hospital, Paris. Thus, our findings suggest that the chronicity index may be valuable as a simplified approach to decision-making in patients with AMR.
抗体介导的排斥反应（AMR）是肾移植受者移植物丢失的主要原因。Banff 分类定义了 AMR 的两类，即活动性和慢性活动性，但随着时间的推移，这种分类变得越来越复杂。为了简化 AMR 的处理方法，我们根据肾移植活检结果开发了活性和慢性指数，并在 147 例活动性或慢性活动性 AMR 患者中检查了它们与移植物存活的相关性，所有患者均具有供体特异性抗体并接受 AMR 治疗。活性指数被确定为 Banff 肾小球炎（g）、肾小管周毛细血管炎（ptc）、血管炎（v）和 C4d 评分的总和，最高得分为 12 分。慢性指数是间质纤维化（ci）、肾小管萎缩（ct）、慢性血管病变（cv）和慢性肾小球病变（cg）评分的总和，后者加倍，最高得分为 15 分。虽然活性指数通常与移植物丢失无关，但慢性指数与移植物丢失显著相关，最佳阈值为 4 或更高可预测移植物丢失。慢性指数≥4 与移植物丢失的相关性独立于与移植物丢失相关的其他参数，包括活检时的估计肾小球滤过率、慢性活动性（与活动性）AMR、具有新发性（与持续性/反弹）供体特异性抗体的 AMR、Banff（g+ptc）评分、同时存在 T 细胞介导的排斥反应和活检后供体特异性抗体减少。在巴黎 Necker 医院的 61 例独立队列中证实了慢性指数≥4 与移植物丢失的相关性。因此，我们的研究结果表明，慢性指数可能是 AMR 患者决策的一种有价值的简化方法。
