基于宏基因组二代测序技术检测肾移植术后肺部感染的病原学研究

Pathogeny research of pulmonary infection after renal transplantation based onmetagenomics nextgeneration sequencing

目的:探讨肾移植术后肺部感染病原学特点和宏基因组二代测序技术(mNGS)的诊断价值。方法:选取2018年1月至2021年1月在西安交通大学第一附属医院肾移植科确诊的40例肺部感染受者,并通过常规病原体检测方法和mNGS明确病原体。常规病原体检测方法包括:血培养、支气管肺泡灌洗液(BALF)和痰培养及涂片染色、肺部组织病理、抗原检测和PCR等,mNGS则进行BALF检测寻找病原体。通过比较两种检测方法的结果,给予精准抗感染治疗,并对其临床资料进行回顾性分析。结果:最终36例受者治愈出院,4例死亡。40例肺部感染受者,BALF的mNGS病原体检测呈阳性者37例,阴性3例,其检测敏感性92.5%,其中单一型肺部感染15例,混合型肺部感染22例,包括8例以细菌感染为主,9例病毒感染为主和20例真菌感染为主,耶氏肺孢子菌(20/40,50%)和人巨细胞病毒(10/40,25%)是最为常见的病原体。相比之下,通过常规病原体检测方法阳性者12例,检出率仅为30%,两种检测方法差异有统计学意义(χ^(2)=32.92,P<0.05);对于混合型肺部感染两种检测方法诊断率分别为55%和10%,两者差异具有统计学意义(χ^(2)=18.46,P<0.05),而单一型肺部感染诊断率分别为30%和20%,两者差异无统计学意义(χ^(2)=2.99,P>0.05)。结论:与常规病原体检测方法相比,mNGS在病原体种类和分布、检测时效、敏感性、混合型感染诊断率及受益等方面更具优势,利用mNGS可更加高效寻找肾移植术后肺部感染的病原体,采取精准化治疗,减少费用,提高治愈率,值得广泛推广应用。

Objective Discuss the etiological characteristics of pulmonary infection after renal transplantation and the diagnostic value of metagenomics nextgeneration sequencing(mNGS)technique.Methods A total of 40 patients with pulmonary infection who were admitted to the Department of Renal Transplantation of the First Affiliated Hospital of Medical College,Xi'an Jiaotong University from January,2018 to January,2021 were selected,and identification of pathogens through routine pathogen detection methods and mNGS.The routine pathogen detection methods included:blood culture,bronchoalveolar lavage fluid(BALF)and sputum culture and smear staining,lung histopathology,antigen detection and PCR,etc.BALF were used to search for pathogens by mNGS.Combined with the results of the two groups to give accurate anti-infection treatment,the clinical data were retrospectively analyzed.Results Eventually 36 patients were cured and discharged,and 4 patients deaths.In 40 cases of pulmonary infection,the BALF mNGS pathogens detection of BALF was positive in 37 cases and negative in 3 patients,with a detection sensitivity of 92.5%.In addition,there were 15 cases of single pulmonary infection and 22 cases of mixed pulmonary infection,including 8 cases of bacterial infection,9 cases of viral infection and 20 cases of fungal infection,among which pneumocystis(20/40,50%)and cytomegalovirus(10/40,25%)were the most common.In contrast,the positive rate of pathogens by routine detection were only 30%(12/40),and the difference between the two detection methods was statistically significant(χ^(2)=32.92,P<0.05).The diagnostic rates of mixed pulmonary infection were 55%and 10%respectively,the difference was statistically significant(χ^(2)=18.46,P<0.05),the single type pulmonary infection was 30%and 20%respectively,the difference was not statistically significant(χ^(2)=2.99,P>0.05).Conclusions mNGS has more advantages than routine pathogen detection methods in terms of pathogen species and distribution,detection time,sensitivity,mixed infection diagnosis rate and benefit.Using mNGS can be more efficient to find pathogens of pulmonary infection after renal transplantation,take accurate treatment,reduce costs,and improve cure rate,such as worth wide application..