BACKGROUND Extending survival after heart transplant (HT) is of paramount importance for childhood recipients of HT. Acute rejection is a significant event, and biopsy remains the most specific means for distinguishing between cellular (ACR) and antibody-mediated rejection (AMR). METHODS All children in the Pediatric Heart Transplant Society Registry who underwent HT between January 2015 and June 2022 and had ≥1 rejection episode were included. Survival was compared between AMR and ACR-only. Secondary outcomes of infection, malignancy, and cardiac allograft vasculopathy (CAV) were assessed. Risk factors for graft loss after AMR were identified using Cox proportional hazard modeling. RESULTS Among 906 children with rejection, 697 (77%) with complete biopsy information were included. AMR was present on biopsy in 261 (37%) patients; ACR-only was present in 436 (63%). Time to rejection was earlier for AMR, median time from HT to rejection 0.11 versus 0.29 years, p = 0.0006. Survival after AMR in the 1st year was lower than survival after ACR-only. Predictors of graft loss after AMR were younger age at HT, congenital heart disease, and rejection with hemodynamic compromise. There was no difference in time to CAV, infection, or malignancy after rejection between groups. CONCLUSIONS The largest analysis of pediatric HT rejection with biopsy data to identify AMR underscores the continued importance of AMR on survival. AMR is associated with higher graft loss versus ACR when occurring in the first-year post-HT. Predictors of graft loss after AMR identify patients who may benefit from increased surveillance or augmented maintenance immunosuppression.

中文翻译：

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小儿心脏移植受者抗体介导的排斥反应活检诊断后的临床结果。


背景 延长心脏移植 （HT） 后的生存期对于儿童期 HT 受者至关重要。急性排斥反应是一个重要事件，活检仍然是区分细胞 （ACR） 和抗体介导的排斥反应 （AMR） 的最特异性手段。方法 纳入儿科心脏移植协会登记处所有在 2015年1月至 2022年6月期间接受 HT 且发生 ≥1 次排斥反应的儿童。比较 AMR 和仅 ACR 之间的生存率。评估感染、恶性肿瘤和心脏同种异体移植血管病变 （CAV） 的次要结局。使用 Cox 比例风险模型确定 AMR 后移植物丢失的危险因素。结果 在 906 例排斥反应患儿中，纳入 697 例 （77%） 具有完整的活检信息。261 例 （37%） 患者活检显示 AMR;436 例 （63%） 仅存在 ACR。AMR 的排斥反应时间较早，从 HT 到排斥反应的中位时间为 0.11 年和 0.29 年，p = 0.0006。第 1 年 AMR 后的生存率低于仅 ACR 后的生存率。AMR 后移植物丢失的预测因素是 HT 年龄较小、先天性心脏病和排斥反应伴血流动力学损害。两组排斥反应后发生 CAV、感染或恶性肿瘤的时间没有差异。结论 最大的儿科 HT 排斥反应分析与活检数据以确定 AMR 强调了 AMR 对生存的持续重要性。当发生在 HT 后第一年时，AMR 与 ACR 相比，移植物损失更高。AMR 后移植物丢失的预测因子可识别可能从增加监测或增强维持免疫抑制中受益的患者。