评估儿童心脏移植术后早期巨细胞病毒(CMV)感染率，同时探讨移植术后受者CMV感染与淋巴细胞亚群的相关性。

回顾性分析2021~2024年中国医学科学院阜外医院行心脏移植的60例儿童受者病例资料。根据术后早期(180 d内)是否出现CMV DNA血症，分为CMV感染组(n＝24)和非感染组(n＝36)，比较两组受者术前和术后1、3、7、14、30、90和180 d淋巴细胞亚群(CD4^＋ T细胞绝对值、CD8^＋ T细胞绝对值、CD4^＋/CD8^＋比值、CD19^＋ B细胞绝对值、CD56^＋ NK细胞绝对值)。根据受者术前是否存在CMV特异性IgG抗体，分为CMV-IgG阳性组(n＝47)和阴性组(n＝13)，比较术后CMV DNA血症阳性比例。非正态分布计量资料组间比较采用Wilcoxon秩和检验，计数资料组间比较采用χ²检验。P<0.05为差异有统计学意义。

儿童心脏移植术后早期CMV感染率为40.0%(24/60)，以术后30~90 d多见。术后CMV感染组与非感染组性别、年龄、体重、身高、体质指数、原发病、心衰程度、免疫抑制方案和总住院时间差异均无统计学意义(χ²/Z＝0.188、－0.417、－0.294、－0.936、－0.589、1.405、0.188、0.262和－1.238，P均>0.05)。CMV感染组受者术后180 d CD4^＋/CD8^＋比值低于非感染组(Z＝－2.233)，CD56^＋ NK细胞绝对值高于非感染组(Z＝－2.414和－2.535)，差异均有统计学意义(P均<0.05)。术前CMV-IgG阳性组和阴性组受者术后CMV DNA血症阳性比例分别为17/47和7/13，差异无统计学意义(χ²＝1.326，P>0.05)。

儿童心脏移植术后CMV感染较为常见。移植后早期CMV感染受者外周血CD4^＋/CD8^＋比值降低提示机体处于免疫抑制状态。术前CMV-IgG抗体阴性受者，术后更易出现CMV感染。儿童心脏移植受者可定期监测淋巴细胞亚群，评估受者免疫功能，预测CMV感染风险。

To evaluate the incidence of cytomegalovirus (CMV) infection in the early postoperative period following pediatric heart transplantation, and to explore the association between CMV infection and peripheral blood lymphocyte subsets.

A retrospective study analyzed 60 pediatric recipients who underwent heart transplantation between 2021 and 2024 in Fuwai Hospital, Chinese Academy of Medical Sciences. The recipients could be categorized into two groups depending on CMV-DNAemia occurred in the early postoperative period (within 180 days) following pediatric heart transplantation (CMV infection group, n=24; non- CMV infection group: n=36), and the differences of lymphocyte subsets (CD4⁺ T cells, CD8⁺ T cells, CD4⁺ /CD8⁺ ratio, CD19⁺ B cells, CD56⁺ NK cells) were compared at different time points (preoperation, postoperative 1, 3, 7, 14, 30, 90, 180 days). The recipients could be categorized into two groups depending on pretransplant serologic recipient CMV status (CMV-IgG positive group, n=47; CMV-IgG negative group, n=13), and the differences of CMV infection incidence were compared. For the comparison between groups, the Wilcoxon rank-sum test was used for non-normally distributed continuous data, and the chi-square test was used for categorical data. P<0.05 was considered statistically significant.

The incidence of postoperative CMV infection was 40.0% (24/60) in the early postoperative period following pediatric heart transplantation, and more common at 30-90 days. There were no statistically significant differences in preoperative general data (age, weight, height, BMI, disease type, degree of heart failure, immunosuppressive therapy, and length of stay) between infection and non-infection groups (χ²/Z=0.188, -0.417, -0.294, -0.936, -0.589, 1.405, 0.188, 0.262, and -1.238; all P>0.05). The CD4⁺ /CD8⁺ ratio in the CMV infection group was lower at 180 days after surgery (Z=-2.233), and the absolute value of CD56⁺ NK cells was higher (Z=-2.414, -2.535), and the differences were statistically significant (all P<0.05). The proportion of positive CMV DNAemia in the preoperative CMV-IgG positive group and the negative group was 17/47 and 7/13, respectively, and there was no statistically significant difference (χ²=1.326, P>0.05).

CMV infection is common in pediatric heart transplantation. A decrease in the CD4⁺ /CD8⁺ ratio in pediatric recipients with early CMV infection indicates the immunosuppression. Recipients with negative pre-transplant CMV-IgG antibody have a higher risk of CMV infection after surgery. Children who have undergone heart transplantation can have their lymphocyte subsets regularly monitored to assess their immune function and predict the risk of CMV infection.