目的 总结9例肺移植儿童的临床特点，探讨肺移植儿童的预后及免疫状况，为临床诊治提供参考。方法 回顾性分析2019年1月至2023年6月在我院住院诊治的9例肺移植患儿的临床资料及预后情况。结果 9例患儿，男3例、女6例。基础病包括肺纤维化、特发性肺动脉高压、闭塞性细支气管炎、肺间质病变及肺囊性纤维化。所有患儿均为双肺移植，肺移植年龄7.83（4.79~9.34）岁。4例患儿发生支气管狭窄，其中3例为<7岁患儿，且2例诊断为慢性移植肺功能障碍相关闭塞性细支气管炎综合征（BOS）。与正常参考值比较，6例患儿CD3⁺T、CD8⁺T细胞比例增高，4例CD4⁺T细胞比例、8例CD4⁺T/CD8⁺T降低，<7岁患儿免疫异常更为显著。2例BOS患儿均出现移植后淋巴组织增生性疾病（PTLD），均经活检诊断为弥漫大B细胞淋巴瘤。随访2.67（1.67~3.17）年，2例BOS患儿分别于移植后1.33年、1年死亡，均死于Ⅱ型呼吸衰竭。>7岁患儿均居家口服免疫抑制药物，可进行简单体力活动及日常生活。结论 BOS、PTLD是<7岁双肺移植儿童危及生命的并发症，与T淋巴细胞亚群异常密切相关。低年龄儿童肺移植后生存期短，其肺部结构和免疫状况是影响预后的关键因素。随着肺移植儿童数量的增加，需进一步扩大病例数量及深化年龄分组研究，以优化临床诊治策略，延长患儿生存期并提高生活质量。

Objective To summarize the clinical characteristics of 9 children who underwent lung transplantation, explore the prognosis and immune profiles of these children, and furnish references for clinical diagnosis and treatment. Methods A retrospective analysis was conducted on the clinical data and prognosis of 9 children who underwent lung transplantation and were hospitalized in our hospital from January 2019 to June 2023. Results Among the 9 children, 3 were male and 6 were female. The underlying diseases comprised pulmonary fibrosis, idiopathic pulmonary arterial hypertension, obliterative bronchiolitis, interstitial lung disease, and cystic fibrosis. All children underwent bilateral lung transplantation, with an average age of 7.83 (4.79 - 9.34) years at the time of transplantation. Four children developed bronchial stenosis, among which all 3 children were under 7 years old and 2 were diagnosed with bronchiolitis obliterans syndrome (BOS) related to chronic allograft dysfunction. Compared with the normal reference values, the proportions of CD3⁺T and CD8⁺T cells were elevated in six children, and the proportions of CD4⁺T cells and CD4⁺T/CD8⁺T were decreased in four and eight children, respectively. Immune abnormalities were more pronounced in children under 7 years old. Two children with BOS developed post-transplant lymphoproliferative disorder (PTLD), and both were diagnosed with diffuse large B-cell lymphoma through biopsy. The follow-up period was 2.67 (1.67-3.17) years. Two children with BOS died at 1.33 years and 1 year after transplantation, both succumbing to typeⅡ respiratory failure. All children over the age of seven were taking oral immunosuppressive drugs at home and were capable of performing simple physical activities and daily life. Conclusion BOS and PTLD are life-threatening complications for children under 7 years old who have undergone bilateral lung transplantation, being closely associated with abnormal T lymphocyte subsets. The survival period after lung transplantation is shorter for younger children, and their lung structure and immune status are key factors influencing prognosis. With the increasing number of children undergoing lung transplantation, it is necessary to further expand the case numbers and deepen age group studies to optimize clinical diagnosis and treatment strategies, prolong the survival period of children, and enhance their quality of life.