血液重症患儿应用宏基因组二代测序的病原学分析及诊断价值

Pathogenic analysis and diagnostic value of metagenomic next-generation sequencing in critically ill children with hematological disorders

目的探讨宏基因组二代测序(mNGS)在血液重症患儿中的应用并评估其诊断价值。方法回顾性分析中南大学湘雅医院儿童重症监护病房2019年9月至2022年6月行传统培养检测和mNGS检测的血液病、肿瘤和造血干细胞移植后患儿的临床资料,分析对比传统培养和mNGS对病原体的检出率、诊断价值。结果50例患儿中,男29例,女21例,中位年龄9.00(4.75~13.00)岁。送检mNGS检测标本共60份,其中40份血液,10份支气管肺泡灌洗液,7份脑脊液,骨髓、皮肤、胸水各1份。mNGS检测标本阳性结果49份,其中病毒20例,细菌14例,混合8例,真菌7例。本研究中mNGS检出率显著高于传统病原体培养(81.7%vs 16.7%),差异具有统计学意义(P<0.01)。以临床诊断病例为标准,mNGS灵敏度显著高于传统培养(85.2%vs 29.6%),差异具有统计学意义(P<0.01),而其特异度与传统培养比较(50.0%vs 83.3%)差异无统计学意义(P>0.05)。结论mNGS比传统病原体培养具有更高的检出率及灵敏度,能早期明确病毒、真菌及混合感染的情况,可为血液重症患儿的精准治疗提供有力帮助。

Objective To explore the application of metagenomic next-generation sequencing(mNGS)in critically ill children with hematological disorders and evaluate its diagnostic value.Methods A retrospective analysis was conducted on the clinical data of children with hematological diseases,tumors,and hematopoietic stem cell transplantation who underwent traditional culture and mNGS testing in the pediatric intensive care unit of the Xiangya Hospital,Central South University from September 2019 to June 2022.The detection rate and diagnostic value of traditional culture and mNGS for pathogens were analyzed and compared.Results Among the 50 patients,there were 29 males and 21 females,with a median age of 9.00(4.75-13.00)years.A total of 60 samples were sent for mNGS testing,including 40 blood samples,10 bronchoalveolar lavage fluid samples,7 cerebrospinal fluid samples,and 1 bone marrow,1 skin,and 1 pleural fluid sample each.49 positive samples were detected by mNGS,including 20 cases of viruses,14 cases of bacteria,8 cases of mixed samples,and 7 cases of fungi.The detection rate of mNGS in this study was significantly higher than that in traditional pathogen culture(81.7%vs 16.7%),and the difference was statistically significant(P<0.01).Based on clinical diagnostic cases,the sensitivity of mNGS was significantly higher than that of traditional culture(85.2%vs 29.6%),with a statistically significant difference(P<0.01),while its specificity was not statistically significant(P>0.05)compared to traditional culture(50.0%vs 83.3%).Conclusions mNGS has a higher detection rate and sensitivity than traditional pathogen culture,and can early identify viral,fungal,and mixed infections,providing strong assistance for precise treatment of critically ill children with hematological conditions.