病原体靶向测序技术在儿科肺部感染病原学检测中的应用价值

Application Value of Pathogen Targeted Sequencing Technology in Etiological Detection of Pediatric Pulmonary Infection

摘要: 背景：儿童社区获得性肺炎(CAP)是儿科常见的感染性疾病，其病原体复杂多样，传统的病原学检测方法如痰液和血液培养在多重病原体感染的识别方面存在局限。靶向二代测序通过高效的基因检测和生物信息分析，实现了对多种致病病原微生物的快速识别，特别适用于复杂的病原体检测。目的：本研究旨在探讨tNGS技术在儿科CAP患者中病原体检测的应用价值，通过对比tNGS结果与传统实验室检测结果，评估tNGS在检测敏感性、复合感染识别及耐药基因筛查方面的优势。方法：选取2023年7月至2024年6月在广州某医院住院的705例儿科CAP患者，对其支气管肺泡灌洗液进行tNGS检测，并与肺泡灌洗液常规培养及血清学检测结果进行对比分析。结果：在传统培养方法中，110株病原菌被成功培养，检出率为14.75%，主要病原体包括流感嗜血杆菌、金黄色葡萄球菌、白色念珠菌、肺炎链球菌和鲍曼不动杆菌。相较之下，tNGS阳性检出699例，检出率高达99.15%；tNGS检测在705例患者中单一感染致病性病原菌或条件致病菌的病例为52例(7.38%)，未检出病原菌的病例数为6例(0.85%)，其余病例均检出双重或多重病原菌感染。tNGS检出的主要致病性病原体依次为肺炎支原体、人呼吸道合胞病毒B型、人类腺病毒B型、鼻病毒A型及人呼吸道病毒3型，复合感染中最常见的是肺炎支原体和人类腺病毒B型。耐药基因检测结果显示，tNGS检出耐药基因532例，以肺炎支原体的Mp_23S_rRNA (A2063G)和金黄色葡萄球菌的mecA为主，分别占比80.3%和8.46%。血清学检测显示，检出率最高的病原体包括肺炎支原体、呼吸道合胞病毒、甲型流感病毒、腺病毒和嗜肺军团菌。tNGS检测与传统方法的检测结果相比，差异显著(54.6% vs. 99.1%, P < 0.01)，一致性较低(Kappa值 = 0.241，P = 0.019)。结论：tNGS技术在儿科肺部感染病原体的检测中表现出显著的敏感性优势，不仅提高了病原菌的检出率，特别是在识别儿科肺部感染常见的难培养病原体和复合感染方面具有显著优势，还提供了耐药基因的高效筛查手段。tNGS技术在复杂感染的早期诊断及精准治疗方案制定中具有较高的临床应用价值。

Abstract: Background: Children’s community-acquired pneumonia (CAP) is a common infectious disease in pediatrics. Its pathogens are complex and diverse. Traditional etiological detection methods, such as sputum and blood culture, have limitations in the identification of multiple pathogen infections. Through efficient gene detection and bioinformation analysis, targeted second-generation sequencing realizes rapid identification of a variety of pathogenic microorganisms, especially for complex pathogen detection. Objective: The purpose of this study was to investigate the application value of tNGS technology in pathogen detection in pediatric CAP patients, and to evaluate the advantages of tNGS in detection sensitivity, identification of complex infection and screening of drug resistance genes by comparing the results of tNGS with those of traditional laboratory tests. Methods: 705 pediatric patients with CAP admitted to a hospital in Guangzhou from July 2023 to June 2024 were selected for tNGS detection of bronchoalveolar lavage fluid, and compared with the results of routine culture and serological detection of alveolar lavage fluid. Results: In the traditional culture method, 110 strains of pathogenic bacteria were successfully cultured, the detection rate was 14.75%, the main pathogens included Haemophilus influenzae, Staphylococcus aureus, Candida albicans, Streptococcus pneumoniae and Acinetobacter baumannii. In contrast, 699 cases of tNGS were detected, the detection rate was as high as 99.15%. Among the 705 patients, 52 (7.38%) were infected with single pathogenic bacteria or opportunistic pathogens, 6 (0.85%) were not detected by tNGS, and the other cases were detected with double or multiple pathogenic bacteria. The main pathogenic pathogens detected by tNGS were Mycoplasma pneumoniae, human respiratory syncytial virus type B, human adenovirus type B, rhinovirus type A and human respiratory virus type 3, and the most common complex infections were Mycoplasma pneumoniae and human adenovirus type B. The results of drug resistance gene detection showed that 532 cases of drug resistance genes were detected by tNGS, mainly Mp_23S_rRNA (A2063G) of Mycoplasma pneumoniae and mecA of Staphylococcus aureus, accounting for 80.3% and 8.46% respectively. Serological tests showed that the pathogens with the highest detection rate included Mycoplasma pneumoniae, respiratory syncytial virus, influenza A virus, adenovirus and Legionella pneumophila. The results of tNGS detection were significantly different from those of traditional methods (54.6% vs. 99.1%, P < 0.01), and the consistency was low (Kappa = 0.241, P = 0.019). Conclusion: tNGS technology has a significant sensitivity advantage in the detection of pathogens of pediatric pulmonary infection, which not only improves the detection rate of pathogens, but also has a significant advantage in the identification of common difficult-to-culture pathogens and complex infections in pediatric pulmonary infection, and also provides an efficient screening method for drug-resistant genes. tNGS technology has high clinical application value in the early diagnosis of complex infection and the formulation of precise treatment plan.