目的 分析急性巨核细胞白血病（AMKL）患儿免疫表型和遗传学特征，为临床诊断及治疗提供相关依据。 方法 回顾性分析2017年9月至2024年12月来院就诊的45例AMKL患儿的临床资料，其中男23例，女22例，包括唐氏综合征相关AMKL（DS-AMKL）患儿7例，non-DS-AMKL患儿38例。应用流式细胞术进行免疫表型检测分析，G显带技术进行染色体核型分析，RT-PCR和测序技术进行融合基因检测分析。 结果 AMKL患儿初次就诊时最常见的临床表现为皮肤瘀斑或瘀点，中位数血小板17（3 ~ 222）× 10⁹/L。所有患儿骨髓幼稚细胞均至少表达血小板相关糖蛋白CD41a、CD42b和CD61中的一种，表达率最高的为CD41a（84.4%）。与non-DS-AMKL相比，DS-AMKL患儿中CD7、CD13、CD36有更高的检出率（P < 0.05）；而CD41a在non-DS-AMKL中有更高的检出率（P < 0.05）。41例患儿进行了染色体核型分析，检出染色体异常33例（80.5%），其中复杂核型14例（34.1%）。21例non-DS-AMKL患儿进行了融合基因检测，检出6例CBFA2T3：：GLIS2，2例NUP98：：KDM5A，NUP98：：ING4、RBM15：：MKL1和KMT2A：：MLLT3各1例。CBFA2T3：：GLIS2阳性患儿具有特征性的免疫表型，即都高表达CD56，不表达HLA-DR和CD36。 结论 儿童AMKL是一类高度异质性的疾病，具有相对特征性的免疫表型，染色体异常率高，最常见的融合基因为CBFA2T3：：GLIS2。通过免疫表型和遗传学致病分子检测及分析，能够提高对AMKL的识别和诊断，更好地进行预后分层和选择治疗方案。

Objective To analyze the immunophenotypic and genetic characteristics of children with acute megakaryoblastic leukemia （AMKL） and provide relevant evidence for clinical diagnosis and treatment. Methods A retrospective analysis was conducted on the clinical data of 45 children with AMKL who were admitted to the hospital from September 2017 to December 2024， including 23 males and 22 females. Among them， 7 cases were Down syndrome-associated AMKL （DS-AMKL）， and 38 cases were non-DS-AMKL. Flow cytometry was used for immunophenotypic analysis， G-banding for karyotype analysis， and RT-PCR and sequencing for fusion gene detection. Results The most common clinical manifestation of AMKL children at initial diagnosis was skin ecchymosis or petechiae， with a median platelet count of 17（3 ~ 222）× 10⁹/L. All children expressed at least one of the platelet-associated glycoproteins CD41a， CD42b， or CD61 in bone marrow blasts， with CD41a having the highest expression rate （84.4%）. Compared to non-DS-AMKL， DS-AMKL children had significantly higher detection rates of CD7， CD13， and CD36 （P < 0.05）， while CD41a had a significantly higher detection rate in non-DS-AMKL （P < 0.05）. Karyotype analysis was performed in 41 children， and chromosomal abnormalities were detected in 33 cases （80.5%）， including 14 cases （34.1%） with complex karyotypes. Fusion gene testing was performed in 21 non-DS-AMKL children， revealing 6 cases of CBFA2T3：：GLIS2， 2 cases of NUP98：：KDM5A， and 1 case each of NUP98：：ING4， RBM15：：MKL1， and KMT2A：：MLLT3. Children positive for CBFA2T3：：GLIS2 exhibited a characteristic immunophenotype， with high expression of CD56 and no expression of HLA-DR or CD36. Conclusions Pediatric AMKL is a highly heterogeneous disease with relatively characteristic immunophenotypes， a high rate of chromosomal abnormalities， and CBFA2T3：：GLIS2 being the most common fusion gene. Immunophenotypic and genetic molecular testing and analysis can improve the diagnosis and identification of AMKL， enabling better prognostic stratification and treatment selection.