二代测序在脓毒血症患者病原学诊断中的应用

摘要

Sepsis is a life-threatening infection demanding accurate and fast diagnosis of pathogen for right antibiotics.In current practice,culture-based methods are still the standard approach of etiological diagnosis of sepsis.Practically,these methods have disadvantages including long turnaround time and low sensitivity. Although molecular assays,such as polymerase chain reaction(PCR)-based methods have been established for sepsis,the spectrum of the detection is limited to known pathogens listed on the panel.In the last few years,the next-generation sequencing(NGS)has been constantly improving and stepped into clinical practice,providing a powerful tool with advantages including short turnaround time,full spectrum and semiquantitative analysis.Although NGS has clear advantages compared with culture-based methods,we are facing the following challenges:few acknowledged criteria of sequencing result explanation have been established;the relationship between sequencing results and treatment effects is undetermined;and the drug resistance gene detection is usually with low sensitivity.Besides,large-scale study comparing NGS with traditional etiological diagnosis methods is missing.Thus,NGS still needs high-level evidence to support its clinical application.%脓毒血症是一种严重威胁生命的感染,精准、快速的病原学诊断可帮助临床医师优化抗菌药物的使用.目前,基于病原菌培养的方法仍是脓毒血症病原学诊断的主要手段,但具有耗时长、灵敏度低等不可忽视的缺点.近年来出现了一些不依赖培养的病原学诊断方法,其中基于聚合酶链反应(polymerase chain reaction,PCR)的方法已发展较为成熟.但PCR只能检测已知的特定病原体,临床定量PCR仅用于检测病毒及少数细菌,脓毒血症中的病原体PCR多仅为定性检测.目前,二代测序技术不断成熟并用于临床,成为病原学诊断的有力手段.与血培养等传统病原学检测方法相比,其具有快速、非选择性、可定量或半定量分析的优点.现阶段二代测序仍存在公认判读标准缺乏、测序结果与治疗关系不明确、耐药基因检测困难等不足,亦缺乏较大规模的二代测序与传统诊断方法比较验证的研究结果,尚有待更高级的循证医学证据支持.