{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T06:05:50Z","timestamp":1790057150430,"version":"4.0.1"},"reference-count":40,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      <jats:italic>Legionella<\/jats:italic>\n                      pneumonia (LP), primarily caused by\n                      <jats:italic>Legionella pneumophila<\/jats:italic>\n                      , is a clinically important subtype of community-acquired pneumonia (CAP) associated with substantial morbidity and mortality. However, the microbial characteristics and functional profiles of LP remain insufficiently understood.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      In this study, metagenomic next-generation sequencing (mNGS) was used to compare airway microbial communities between patients with LP and those with non-\n                      <jats:italic>Legionella<\/jats:italic>\n                      CAP.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 60 patients were included, comprising 23 patients with LP patients and 37 patients with non-\n                      <jats:italic>Legionella<\/jats:italic>\n                      CAP patients. Airway microbial diversity and composition differed between groups, although the between-group effect size was modest and residual confounding could not be excluded. The LP group showed higher relative abundance of\n                      <jats:italic>Legionella pneumophila<\/jats:italic>\n                      and selected opportunistic species, whereas several oral commensal-associated species were relatively enriched in non-\n                      <jats:italic>Legionella<\/jats:italic>\n                      CAP. In the pooled 60-patient cohort, selected microbial species were associated with inflammatory and clinical severity markers; these associations were not disease-specific and do not imply causality. Inferred functional profiles also differed between groups. Exploratory machine-learning models showed high internal discriminatory performance, with XGBoost yielding the highest mean AUC, but the small cohort and lack of external validation limit conclusions regarding diagnostic utility.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      In this small retrospective cohort, LP was associated with differences in airway microbial composition and inferred functional potential compared with a heterogeneous non-\n                      <jats:italic>Legionella<\/jats:italic>\n                      CAP group. Because the study was observational, the groups differed in important clinical characteristics, and the pooled association analyses were not disease-specific, the findings should be considered exploratory and hypothesis-generating. The reproducibility and diagnostic value of microbiota-derived features require confirmation in larger, prospectively collected, independent cohorts.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1900957","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T05:40:13Z","timestamp":1790055613000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Metagenomic next-generation sequencing reveals airway microbial dysbiosis and functional alterations in Legionella pneumophila pneumonia"],"prefix":"10.3389","volume":"16","author":[{"given":"Hao","family":"Zhang","sequence":"first","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenjing","family":"Zou","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weiwei","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Medicine, Dinfectome Inc.","place":["Nanjing, Jiangsu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Lishui District People\u2019s Hospital","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lijun","family":"Ren","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengying","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Di","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jia","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Medicine, Dinfectome Inc.","place":["Nanjing, Jiangsu, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanzhe","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingjing","family":"Ding","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University","place":["Nanjing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1016\/j.xcrm.2025.102289","article-title":"Lung virome convergence precedes hospital-acquired pneumonia in intubated critically ill patients","volume":"6","author":"Anani","year":"2025","journal-title":"Cell Rep. 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