Letermovir (LTV) prophylaxis is effective in reducing the incidence of clinically significant cytomegalovirus (CMV) infection (cs CMVi) after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Since our centre began administering LTV prophylaxis in June 2022, we have observed a certain increase in the incidence of Epstein–Barr virus (EBV) reactivation after haploidentical HSCT. We retrospectively analysed 230 consecutive patients who underwent haploidentical HSCT with rabbit anti-thymocyte globulin (ATG) from October 2022 to June 2023. The LTV group included 133 patients who received LTV prophylaxis, and the control group included 97 patients who did not receive LTV prophylaxis. At 1 year after HSCT, EBV reactivation was observed in 36 patients (27%) in the LTV group and 13 patients (13%) in the control group (p = 0.012). All patients with EBV reactivation had EBV-DNAemia, and one patient in each group developed EBV-associated posttransplantation lymphoproliferative disorder (PTLD). The proportion of patients with low EBV-DNA loads (> 5 × 102 to < 1 × 104 copies/mL) was greater in the LTV group than in the control group (23% vs. 10%, p = 0.01). The proportion of patients with CMV reactivation was lower in the LTV group than in the control group (35% vs. 56%, p = 0.002). There was no significant difference between the groups in terms of neutrophil and platelet count recovery, the cumulative incidence of acute/chronic graft-versus-host disease, overall survival, cumulative relapse rate or nonrelapse mortality. Our results show that the increased incidence of EBV reactivation may be associated with LTV prophylaxis for CMV after haploidentical HSCT.

中文翻译：

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半相合造血干细胞移植后预防巨细胞病毒感染后 Epstein\u2012Barr 病毒再激活增加


莱特莫韦 （LTV） 预防可有效降低同种异体造血干细胞移植 （allo-HSCT） 后有临床意义的巨细胞病毒 （CMV） 感染 （cs CMVi） 的发生率。自从我们中心于 2022 年 6 月开始进行 LTV 预防以来，我们观察到半相合 HSCT 后 EB 病毒 （EBV） 再激活的发生率有一定增加。我们回顾性分析了 2022 年 10 月至 2023 年 6 月期间连续 230 例接受兔抗胸腺细胞球蛋白 （ATG） 半相合 HSCT 的患者。LTV 组包括 133 例接受 LTV 预防的患者，对照组包括 97 例未接受 LTV 预防的患者。HSCT 后 1 年，LTV 组 36 例患者 （27%） 和对照组 13 例患者 （13%） 观察到 EBV 再激活 （p = 0.012）。所有 EBV 再激活患者均患有 EBV-DNA 血症，每组 1 例患者发生 EBV 相关移植后淋巴组织增生性疾病 （PTLD）。LTV 组低 EBV-DNA 载量 （> 5 × 102 至 < 1 × 104 拷贝/mL） 的患者比例高于对照组 （23% vs. 10%，p = 0.01）。LTV 组 CMV 再激活的患者比例低于对照组 （35% vs. 56%，p = 0.002）。两组之间在中性粒细胞和血小板计数恢复、急性/慢性移植物抗宿主病的累积发生率、总生存期、累积复发率或非复发死亡率方面无显著差异。我们的结果表明，EBV 再激活率的增加可能与半相合 HSCT 后 CMV 的 LTV 预防有关。