BACKGROUND

Desensitization, the process of reducing anti-human leukocyte antigen (HLA) antibodies in sensitized patients awaiting heart transplantation (HT), has unclear efficacy in pediatric HT candidates.

METHODS

Pediatric HT candidates listed at our institution between January 1, 2013 and June 30, 2018 were retrospectively evaluated. Sensitization was defined as the calculated panel reactive antibody (cPRA) ≥ 10% with ≥ 1 a strong positive antibody. The desensitization response was defined as a ≥ 25% reduction in the mean fluorescence intensity (MFI) for ≥ 90% of the strong positive antibodies on follow-up panel reactive antibody (PRA) testing before waitlist removal, HT, or death (data available for 13 patients).

RESULTS

The HT candidates were categorized as sensitized receiving desensitization therapy (ST, n = 14), sensitized not receiving therapy (SNT, n = 18), or non-sensitized (n = 55). A desensitization response was observed in 8 (62%) of the ST upon repeat PRA testing, with the ST responders receiving more doses of intravenous immunoglobulin (IVIG) (8 vs 2, p < 0.05). The anti-HLA class I antibodies were particularly resistant for non-responders (p = 1.9 × 10⁻⁴). The combination of homograft and ventricular assist device was more sensitizing than either alone (p = 3.1 × 10⁻⁴). However, these sensitization risk factors did not impact the desensitization response. The ST was associated with a higher likelihood of remaining listed and a longer waitlist time without substantially impacting the HT rate, waitlist mortality, or early post-HT outcomes.

CONCLUSIONS

Most ST patients had a favorable response to desensitization, with a dose-dependent response observed for IVIG. The anti-HLA class likely impacts the ST response, whereas traditional sensitization risk factors had no impact on the response.

中文翻译：

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小儿心脏移植候选者对脱敏的积极反应的影响和预测因素。

背景

脱敏是在等待心脏移植（HT）的致敏患者中减少抗人白细胞抗原（HLA）抗体的过程，其在小儿HT候选人中的疗效尚不清楚。

方法

对2013年1月1日至2018年6月30日在我院上市的小儿HT候选者进行回顾性评估。敏化度定义为计算的面板反应性抗体（cPRA）≥10％，≥1是强阳性抗体。脱敏反应的定义是，在等待名单移除，HT或死亡之前，后续小组反应性抗体（PRA）测试中≥90％的强阳性抗体的平均荧光强度（MFI）降低≥25％。 （适用于13位患者）。

结果

HT候选人分为致敏接受脱敏治疗（ST，n  = 14），致敏未接受治疗（SNT，n  = 18）或未致敏（n  = 55）。重复PRA测试后，在8例ST中观察到了脱敏反应，ST应答者接受了更多剂量的静脉免疫球蛋白（IVIG）（8 vs 2，p <0.05）。抗HLA I类抗体对无反应者特别有抵抗力（p  = 1.9×10 ^-4）。同种移植物和心室辅助装置的组合比单独使用时更敏感（p  = 3.1×10 ^-4）。但是，这些致敏危险因素并不影响脱敏反应。ST与较高的留在列表中的可能性和更长的等待列表时间相关联，而不会显着影响HT率，等待列表死亡率或HT之后的早期结果。

结论

大多数ST患者对脱敏反应良好，IVIG观察到剂量依赖性反应。抗HLA类可能会影响ST反应，而传统的致敏危险因素对该反应没有影响。