[Analysis of risk factors and prognosis of cytomegalovirus infection post umbilical cord blood stem cell transplantation in children with primary immunodeficiency diseases].

Objective: To investigate the risk factors and outcomes of cytomegalovirus (CMV) infection post umbilical cord blood stem cell transplantation (UCBT) in children with primary immunodeficiency diseases (PID). Methods: Clinical data of 143 PID children who received UCBT in the Children's Hospital of Fudan University from January 2015 to June 2020 were collected retrospectively. CMV-DNA in the plasma was surveilled once or twice a week within 100 days post-UCBT. According to the CMV-DNA test results, children were divided into the CMV-infected group and the CMV-uninfected group. The incidence and risk factors of CMV infection were analyzed. At 1-month post-UCBT, the absolute lymphocyte count, ratio of lymphocyte subsets and immunoglobulin levels were compared between those whose CMV infection developed 1-month later post-UCBT and those not. Mann-Whitney U test and chi-squared test were used for comparision between groups. Kaplan-Meier survival analysis was used to analyze the impact of CMV infection on survival. Results: Among 143 patients, there were 113 males and 30 females, with a age of 14 (8, 27) months at UCBT. Chronic granulomatosis disease (n=49), very-early-onset inflammatory bowel disease (n=43) and severe combined immunodefiency (n=29) were the three main kinds of PID. The rate of CMV infection was 21.7% (31/143), and the time of infection occurring was 44 (31, 49) days post-UCBT. The incidence of recurrent CMV infection was 4.2% (6/143) and refractory CMV infection was 4.9% (7/143).There was no significant difference in the first time CMV-DNA copy and peak CMV-DNA copy during treatment between the recurrent CMV infection group and the non-recurrent CMV infection group (32.8 (18.3, 63.1)×106vs. 22.5 (13.2, 31.9)×106 copies/L, Z=-0.95, P=0.340;35.2 (20.2, 54.6)×106vs. 28.4 (24.1, 53.5)×106copies/L, Z=-0.10, P=0.920), so were those between the refractory CMV infection group and non-refractory CMV infection group (21.8 (13.1, 32.2)×106vs. 25.9 (14.2, 12.2)×106copies/L, Z=-1.04, P=0.299; 47.7 (27.9, 77.6)×106vs. 27.7 (19.7,51.8)×106copies/L, Z=-1.49, P=0.137). The CMV-infected group accepted more reduced-intensity conditioning (RIC) regimen than the CMV-uninfected group (45.2% (14/31) vs. 25.0% (28/112), χ2=4.76, P<0.05). The rate of CMV-seropositive recipients and Ⅱ-Ⅳ acute graft versus host diseases (aGVHD) are significantly higher in the CMV-infected group than the CMV-uninfected group (100% (31/31) vs. 78.6% (88/112), 64.5% (20/31) vs. 26.8% (30/112), χ2=7.98,15.20, both P<0.05). The follow-up time was 31.6 (13.2, 45.9) months, CMV infection had no effect on overall survival (OS) rate (χ2=0.02, P=0.843). There was significant difference in the survival rate among three groups of refractory CMV infection, non-refractory CMV infection and the CMV-uninfected (4/7 vs.95.8% (23/24) vs. 86.6% (97/112), χ2=5.91, P=0.037), while there was no significant difference in the survival rate among three groups of recurrent CMV infection, non-recurrent CMV infection and the CMV-uninfected (5/6 vs. 88.0% (22/25) vs. 86.6% (97/112), χ2=0.43, P=0.896). Children who developed CMV infection after 30 days post-UCBT had lower absolute count and rate of CD4+ T cells and immunoglobulin G (IgG) level than those in the CMV-uninfected group (124.1 (81.5, 167.6) ×106vs. 175.5 (108.3, 257.2) ×106/L, 0.240 (0.164, 0.404) vs. 0.376 (0.222, 0.469), 9.3 (6.2, 14.7) vs. 13.6 (10.7, 16.4) g/L, Z=-2.48, -2.12,-2.47, all P<0.05), but have higher rate of CD8+T cells than those in CMV-uninfected group (0.418 (0.281, 0.624) vs. 0.249 (0.154, 0.434), Z=-2.56, P=0.010). Conclusions: RIC regimen, grade Ⅱ-Ⅳ aGVHD and CMV-seropositive recipients are the main risk factors associated with CMV infection in PID patients post-UCBT. Survival rate of children with refractory CMV infection after UCBT is reduced. Immune reconstitution in children after UCBT should be regularly monitored, and frequency of CMV-DNA monitoring should be increased for children with delayed immune reconstitution.目的： 探讨原发性免疫缺陷病（PID）患儿脐带血干细胞移植（UCBT）后发生巨细胞病毒（CMV）感染的危险因素及其对预后的影响。 方法： 回顾性研究。收集2015年1月至2020年6月在复旦大学附属儿科医院接受UCBT的143例PID患儿的临床资料。UCBT后100 d内患儿每周进行1~2次血浆CMV-DNA检测，根据结果分为CMV感染组与未感染组，分析UCBT后100 d内CMV感染的发生率及危险因素。比较移植1个月后CMV感染患儿与未感染患儿在移植后1个月时的外周血中淋巴细胞亚群绝对计数、比例及免疫球蛋白水平的差异。组间比较采用非参数秩和检验或χ2检验。采用Kaplan-Meier生存分析法比较CMV感染对预后的影响。 结果： 143例患儿中男113例、女30例，移植时年龄为14（8，27）月龄。原发病以慢性肉芽肿病（49例）、极早发型炎症性肠病（43例）及重症联合免疫缺陷病（29例）为主。CMV感染率为21.7%（31/143），感染的时间为移植后44（31，49）d。复发性CMV感染率为4.2%（6/143），复发性CMV感染与非复发性CMV感染组间首次CMV-DNA的拷贝及治疗过程中的CMV-DNA拷贝峰值间差异均无统计学意义［32.8（18.3，63.1）×106比22.5（13.2，31.9）×106拷贝/L，Z=-0.95，P=0.340；35.2（20.2，54.6）×106比28.4（24.1，53.5）×106拷贝/L，Z=-0.10，P=0.920］。难治性CMV感染率为4.9%（7/143），难治性CMV感染与非难治性CMV感染组间首次CMV-DNA的拷贝及治疗过程中的CMV-DNA拷贝峰值间差异均无统计学意义［21.8（13.1，32.2）×106比25.9（14.2，12.2）×106拷贝/L，Z=-1.04，P=0.299；47.7（27.9，77.6）×106比27.7（19.7，51.8）×106拷贝/L，Z=-1.49，P=0.137］。CMV感染组中减低强度预处理方案（RIC）的使用率、移植前受者CMV抗体阳性率、移植后Ⅱ~Ⅳ级急性移植物抗宿主病（aGVHD）发生率均明显高于未感染组［45.2%（14/31）比25.0%（28/112），100%（31/31）比78.6%（88/112），64.5%（20/31）比26.8%（30/112），χ2=4.76、7.98、15.20，均P<0.05］。本组患儿随访31.6（13.2，45.9）个月，CMV感染对患儿的总生存率无影响（χ2=0.02，P=0.843）。难治性CMV感染、非难治性CMV感染及未感染组3组患儿的存活率差异有统计学意义［4/7比95.8%（23/24）比86.6%（97/112），χ2=5.91，P=0.037］，而复发性CMV感染、非复发性CMV感染及未感染组3组患儿的存活率差异无统计学意义［5/6比88.0%（22/25）比86.6%（97/112），χ2=0.43，P=0.896］。移植1个月后感染CMV的患儿组在移植后1个月时的CD4+ T细胞绝对计数、比例及IgG水平均显著低于未感染组［124.1（81.5，167.6）×106比175.5（108.3，257.2）×106个/L，0.240（0.164，0.404）比0.376（0.222，0.469），9.3（6.2，14.7）比13.6（10.7，16.4）g/L，Z=-2.48、-2.12、-2.47，均P<0.05］，而CD8+T细胞比例明显高于未感染组［0.418（0.281，0.624）比0.249（0.154，0.434），Z=-2.56，P=0.010］。 结论： PID患儿UCBT后发生CMV感染与RIC方案、发生Ⅱ~Ⅳ级aGVHD及移植前受者CMV抗体阳性有关。UCBT后发生难治性CMV感染的患儿存活率降低。UCBT后应定期进行免疫重建监测，免疫重建延迟患儿可考虑增加CMV-DNA监测频率。.