{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T06:20:20Z","timestamp":1783059620061,"version":"3.54.6"},"reference-count":18,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T00:00:00Z","timestamp":1783036800000},"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>Introduction<\/jats:title>\n                    <jats:p>\n                      Severe\n                      <jats:italic>Legionella pneumophila<\/jats:italic>\n                      (LP) pneumonia is exceedingly rare in children, and clinical data remain scarce.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed the clinical data of 8 children with severe LP pneumonia diagnosed by metagenomic next-generation sequencing (mNGS) at Henan Children\u2019s Hospital between January 2020 and January 2026.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The cohort comprised 3 males and 5 females with a median age of 74 days (range, 8 days to 9 years); neonates accounted for 50.0% (4\/8), and 75.0% (6\/8) had no underlying diseases. Six cases were community-acquired and 2 were hospital-acquired. The predominant manifestations were tachypnea\/dyspnea (100.0%) and fever (87.5%); neonates presented with lethargy and poor feeding. Complications included respiratory failure (87.5%), multiple organ dysfunction (62.5%), and septic shock (37.5%). Procalcitonin, interleukin-6, and LDH were elevated in all cases, while ALB was uniformly decreased. Bilateral pulmonary involvement was seen in 87.5% on chest imaging. mNGS detected LP in all 8 cases (100%), whereas conventional sputum and blood cultures failed to identify LP in any case; LP was isolated from a surgical pus specimen in only 1 case. Co-infections were identified in 50.0%. All initial empirical regimens failed to cover LP. After mNGS-guided targeted therapy, the fluoroquinolone\u2013rifampin combination (2 cases) achieved complete recovery, while macrolide-based regimens yielded variable outcomes. Overall, 50.0% were cured or improved, while 50.0% died or had treatment withdrawn. LP bacteremia and septic shock were uniformly associated with poor outcomes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Severe LP pneumonia in children predominantly affects neonates and can occur without recognized immunodeficiency. mNGS detected LP in all cases where conventional culture failed. In this small cohort, fluoroquinolone-containing combination regimens were associated with favorable outcomes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1865333","type":"journal-article","created":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T05:39:35Z","timestamp":1783057175000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical characteristics and outcomes of severe Legionella pneumophila pneumonia diagnosed by metagenomic next-generation sequencing in children: a case series of 8 patients"],"prefix":"10.3389","volume":"16","author":[{"given":"Yaping","family":"Song","sequence":"first","affiliation":[{"name":"Department of Emergency Medicine, Children\u2019s Hospital Affiliated to Zhengzhou University, Henan Children\u2019s Hospital, Zhengzhou Children\u2019s Hospital","place":["Zhengzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haijun","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Children\u2019s Hospital Affiliated to Zhengzhou University, Henan Children\u2019s Hospital, Zhengzhou Children\u2019s Hospital","place":["Zhengzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Children\u2019s Hospital Affiliated to Zhengzhou University, Henan Children\u2019s Hospital, Zhengzhou Children\u2019s Hospital","place":["Zhengzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yibing","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Children\u2019s Hospital Affiliated to Zhengzhou University, Henan Children\u2019s Hospital, Zhengzhou Children\u2019s Hospital","place":["Zhengzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuelin","family":"Shen","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, National Clinical Research Center for Respiratory Diseases, Beijing Children\u2019s Hospital, Capital Medical University, National Center for Children\u2019s Health","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,3]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"280","DOI":"10.3390\/diagnostics13020280","article-title":"Clinical and Laboratory Diagnosis of Legionella Pneumonia","volume":"13","author":"Bai","year":"2023","journal-title":"Diagnostics (Basel)"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1177\/87551225251366324","article-title":"Doxycycline for legionella pneumonia: expanding treatment horizons through a case series and narrative review","volume":"42","author":"Cabanilla","year":"2025","journal-title":"J. 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