Pediatric heart transplant (HT) candidates experience high waitlist mortality due to a limited donor pool that is constrained in part by anti-HLA sensitization. We evaluated the impact of CDC and Flow donor-specific crossmatch (XM) results on pediatric HT outcomes. All pediatric HT between 1999 and 2019 in the OPTN database were included. Donor-specific XM results were sub-categorized based on CDC and Flow results. Primary outcomes were treated rejection in the first year and time to death or allograft loss. Propensity scores were utilized to adjust for differences in baseline characteristics. A total of 4695 pediatric HT patients with T-cell XM data were included. After propensity score adjustment, a positive T-cell CDC-XM was associated with two times higher odds of treated rejection (OR 2.29 (1.56,3.37)) and shorter time to death/allograft loss (HR 1.50 (1.19,1.88)) compared to a negative Flow-XM. HT recipients who were Flow-XM positive with negative/unknown CDC-XM did not have higher odds of rejection or shorter time to death/allograft loss. An isolated positive B-cell XM was also not associated with worse outcomes. Over the study period XM testing shifted from CDC- to Flow-based assays. A positive donor-specific T-cell CDC-XM was associated with rejection and death/allograft loss following pediatric HT. This association was not observed with a positive T-cell Flow-XM or B-cell XM result alone. The shift away from performing the CDC-XM may result in loss of important prognostic information unless the clinical relevance of quantitative Flow-XM results on heart transplant outcomes is systematically studied.

中文翻译：

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积极交叉配型对儿童心脏移植结果的影响

由于供体库有限，部分受到抗 HLA 致敏作用的限制，小儿心脏移植 (HT) 候选者的候补死亡率很高。我们评估了 CDC 和 Flow 供体特异性交叉配血 (XM) 结果对儿科 HT 结果的影响。OPTN 数据库中 1999 年至 2019 年的所有儿科 HT 均被纳入。捐赠者特定的 XM 结果根据 CDC 和 Flow 结果进行了子分类。主要结局是第一年的治疗排斥反应以及死亡或同种异体移植物丢失的时间。利用倾向得分来调整基线特征的差异。总共纳入了 4695 名具有 T 细胞 XM 数据的儿童 HT 患者。倾向评分调整后，与相比，阳性 T 细胞 CDC-XM 与治疗排斥的两倍高的几率 (OR 2.29 (1.56,3.37)) 和较短的死亡/同种异体移植物丢失时间 (HR 1.50 (1.19,1.88)) 相关。到负 Flow-XM。Flow-XM 呈阳性且 CDC-XM 呈阴性/未知的 HT 接受者并没有出现更高的排斥几率或更短的死亡/同种异体移植物丢失时间。孤立的 B 细胞 XM 阳性也与较差的结果无关。在研究期间，XM 测试从 CDC 检测转向基于 Flow 的检测。阳性供体特异性 T 细胞 CDC-XM 与儿科 HT 后的排斥反应和死亡/同种异体移植物丢失相关。仅用阳性 T 细胞 Flow-XM 或 B 细胞 XM 结果未观察到这种关联。除非系统地研究定量 Flow-XM 结果与心脏移植结果的临床相关性，否则放弃执行 CDC-XM 可能会导致重要预后信息的丢失。