Abstract: Objective　To investigate the scientific outputs of metagenomic next⁃generation sequencing (mNGS) for diagnosis of infection of unknown origin in intensive care units (ICUs), and to decipher the latest advances, frontier trends and spatiotemporal evolution of research hotpots in mNGS for diagnosis of infection of unknown origin in ICUs.  Methods　Publications pertaining to the application of mNGS in diagnosis of infection of unknown origin in ICUs were retrieved from Web of Science Core Collection (WOSCC) from January 1, 2015 to December 31, 2024. The software Scimago Graphica 1.0.30 was employed to generate the network maps of collaboration relationships between countries, international collaborative relationships, author collaborations, institutional collaborative relationships, and a heatmap of journals, and the software VOSviewer 1.6.18 was used to create a heatmap of keywords, and maps of keyword co⁃occurrence clustering and keyword clustering timelines. In addition, the keyword burst map was created using the software CiteSpace 6.3.R3.  Results　A total of 1 707 publications were included in the final analysis, and the number of publications appeared an overall tendency towards a rise from 2015 to 2024, with the largest number of publications seen in 2024 (545 publications). The largest number of publications was recorded in China (1 390 publications), followed by in USA (190 publications) and United Kingdom (31 publications), and China led the global research in this field, with 81% of global related researches linked with China. Frontiers in Cellular and Infection and Microbiology published the largest number of articles (212 publications, 12.42%), and Joseph Derisi was the most productive author (33 publications). Author collaborations occurred within groups; however, there was a lack of close inter⁃group collaborations, with University of California, San Francisco and Chan Zuckerberg Biohub⁃based group seen as the largest collaborative group. High⁃frequency co⁃occurrence keywords included mNGS, infection, diagnosis, case report, community⁃acquired pneumonia and bronchoalveolar lavage fluid, and the 100 most common high⁃frequency co⁃occurrence keywords were assigned into four clusters. Keyword clustering timeline analysis revealed that the research hotspots in this field shifted from virus sequencing and sequence alignment to severe pulmonary infections, and keyword burst analysis showed identification, mNGS and virus as top three keywords with the highest burst intensity.  Conclusions　mNGS was mainly used for identification of viruses among patients with infections of unknown origins in ICUs from 2015 to 2024, and future research priority shifted to pathogen detection for severe pulmonary infections.

Key words: Metagenomic next?generation sequencing, Infection of unknown origin, Intensive care unit, Bibliometric analysis

摘要： 目的　了解宏基因组二代测序（metagenomic next⁃generation sequencing，mNGS）技术用于重症监护室（intensive care unit，ICU）不明原因感染诊断科研产出，揭示mNGS用于ICU不明原因感染诊断的最新进展、前沿趋势及研究热点的时空演变。方法　在Web of Science核心数据集（Web of Science Core Collection，WOSCC）数据库中，检索2015年1月1日至2024年12月31日发表的mNGS用于ICU不明原因感染诊断的相关文献。采用Scimago Graphica 1.0.30软件绘制作者所属国家及国际合作关系网络图、作者合作网络及研究机构合作关系网络图和期刊热图，采用VOSviewer 1.6.18软件绘制关键词热图、关键词共现聚类图以及时间叠加关键词聚类图，同时使用CiteSpace 6.3.R3软件绘制关键词突现图。结果　共有1 707篇文献纳入分析，2015—2024年发文量总体呈上升趋势，以2024年发文量最高（545篇）。中国发文量最高（1 390篇），其次是美国（190篇）和英国（31篇）；中国在该研究领域具有领先优势，全球81%的相关研究均与中国相关。以《Frontiers in Cellular and Infection and Microbiology（细胞与感染微生物学前沿）》发文量最大（212篇，12.42%），Joseph Derisi博士产出最高（33篇）。作者间合作主要存在于各个不同群组内，群组间合作欠密切；以加利福尼亚大学旧金山分校和陈⁃扎克伯格生物中心为核心组成的合作群组规模最大。高频共现关键词包括mNGS、感染、诊断、病例报道、社区获得性肺炎和支气管肺泡灌洗液等，前100个高频共现关键词分为4个聚类；时间叠加关键词聚类图显示，该领域研究重点从病毒测序和序列比对向严重肺部感染转变；关键词突现图显示，识别、mNGS和病毒是突现强度最高的前3个关键词。结论　2015—2024年mNGS主要用于ICU不明原因感染病例病毒识别，未来其研究重点将转向严重肺部感染病原检测。

关键词: 宏基因组二代测序, 不明原因感染, 重症监护室, 文献计量学