{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T23:01:29Z","timestamp":1784761289322,"version":"3.55.0"},"reference-count":42,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,2,17]],"date-time":"2025-02-17T00:00:00Z","timestamp":1739750400000},"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":"Background<\/jats:title>Bloodstream infections (BSIs) caused by Acinetobacter baumannii<\/jats:italic> have been associated with high mortality. To improve the outcomes of patients, this study explored the clinical characteristics and outcomes of patients with BSIs, as well as the phenotypic and genomic characteristics of these isolates.<\/jats:p><\/jats:sec>Methods<\/jats:title>A retrospective cohort study was conducted involving A. baumannii<\/jats:italic> BSIs cases from 2020 to 2023 in a tertiary hospital. The clinical characteristics of all A. baumannii<\/jats:italic> isolates were evaluated. Virulence phenotypes of all isolates were evaluated using the growth curve, biofilm-forming assay, antiserum complement killing, and G.mellonella<\/jats:italic> killing assay. Furthermore, whole-genome sequencing (WGS) was utilized to analyze genomic characteristics.<\/jats:p><\/jats:sec>Results<\/jats:title>The 30-day mortality rate of 67 patients with BSIs was 55.22%. Patients in the death group had significantly lower platelet counts and higher CRP levels than those in the survival group. Additionally, higher rates of antibiotic use (\u22652 classes) and greater carbapenem exposure were observed. Among the isolates, CRAb accounted for 80.6%, ST2 accounted for 76.12%, and KL2\/3\/7\/77\/160 accounted for 65.67%. The predominant KL type was KL3, found in 19.4% of the isolates. All ST2 and KL2\/3\/7\/77\/160 isolates were CRAb. Among the isolates, 90.7% of the CRAb isolates coharbored blaOXA-23<\/jats:sub><\/jats:italic> and blaOXA-66<\/jats:sub><\/jats:italic>, while one coharbored blaNDM-1<\/jats:italic> and blaOXA-23<\/jats:sub><\/jats:italic>. Compared with non-ST2 and non KL2\/3\/7\/ 77\/160 infections, ST2 and KL2\/3\/7\/77\/160 infections had higher mortality rates (66.0% vs. 23.5%, P=0.002; 65.90% vs. 34.78%, P=0.015). Patients with ST2 and KL2\/3\/7\/77\/160 infections underwent more invasive procedures, received two or more antibiotics and carbapenem therapy before isolation, and had lower serum albumin levels. These isolates exhibited significantly higher resistance to antimicrobial agents. No significant differences in virulence phenotypes were observed between the two groups, except for biofilm formation between the ST2 and non-ST2 groups (P=0.035). However, these isolates harbored more virulence genes related to iron uptake and biofilm formation.<\/jats:p><\/jats:sec>Conclusion<\/jats:title>The mortality rate associated with BSIs caused by A. baumannii<\/jats:italic> is high. It is of great significance for clinicians to pay attention to the risk factors of the clinical characteristics of patients and to identify the ST and KL types of the strains causing the infection at an early stage.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fcimb.2025.1549940","type":"journal-article","created":{"date-parts":[[2025,2,17]],"date-time":"2025-02-17T07:04:01Z","timestamp":1739775841000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Exploring the clinical outcomes and molecular characteristics of Acinetobacter baumannii bloodstream infections: a study of sequence types, capsular types, and drug resistance in China"],"prefix":"10.3389","volume":"15","author":[{"given":"Jiao","family":"Chen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanting","family":"Shao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhibin","family":"Cheng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guanghui","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fen","family":"Wan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chenyan","family":"Gao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danqin","family":"Wu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dandan","family":"Wei","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rong","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,2,17]]},"reference":[{"key":"B1","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/S0140-6736(21)02724-0","article-title":"Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis","volume":"399","year":"2022","journal-title":"Lancet"},{"key":"B2","doi-asserted-by":"publisher","first-page":"mgen001080","DOI":"10.1099\/mgen.0.001080","article-title":"Genomics of Acinetobacter baumannii iron uptake","volume":"9","author":"Artuso","year":"2023","journal-title":"Microb. Genom"},{"key":"B3","doi-asserted-by":"publisher","first-page":"1920","DOI":"10.1080\/21505594.2022.2132053","article-title":"Clinical and genomic analysis of virulence-related genes in bloodstream infections caused by Acinetobacter baumannii","volume":"13","author":"Bai","year":"2022","journal-title":"VIRULENCE"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1099\/mgen.0.000878","article-title":"An update to the database for Acinetobacter baumannii capsular polysaccharide locus typing extends the extensive and diverse repertoire of genes found at and outside the K locus","volume":"8","author":"Cahill","year":"2022","journal-title":"Microb. Genom"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1371\/journal.ppat.1011520","article-title":"Portrait of a killer: Uncovering resistance mechanisms and global spread of Acinetobacter baumannii","volume":"19","author":"Cain","year":"2023","journal-title":"PloS Pathog."},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2023.1196774","article-title":"Acinetobacter baumannii in the critically ill: complex infections get complicated","volume":"14","author":"Cavallo","year":"2023","journal-title":"Front. Microbiol."},{"key":"B7","doi-asserted-by":"publisher","first-page":"106929","DOI":"10.1016\/j.micpath.2024.106929","article-title":"Clinical, phenotypic characterization and genomic analysis of the mucoid Acinetobacter baumannii from a teaching hospital","volume":"196","author":"Chen","year":"2024","journal-title":"Microb. Pathog."},{"key":"B8","doi-asserted-by":"publisher","first-page":"274","DOI":"10.1089\/mdr.2022.0310","article-title":"Virulence characteristics and drug resistance of the prevalent capsule types in acinetobacter baumannii","volume":"29","author":"Chen","year":"2023","journal-title":"Microb. Drug Resist."},{"key":"B9","doi-asserted-by":"publisher","first-page":"106","DOI":"10.1016\/j.jinf.2018.10.001","article-title":"Microbiological and Clinical Characteristics of Acinetobacter baumannii Bacteremia: Implications of Sequence type for Prognosis","volume":"78","author":"Chuang","year":"2019","journal-title":"J. Infect."},{"key":"B10","doi-asserted-by":"publisher","first-page":"S565","DOI":"10.1093\/cid\/ciz830","article-title":"Treatment options for carbapenem-resistant gram-negative bacterial infections","volume":"69","author":"Doi","year":"2019","journal-title":"Clin. Infect. Dis."},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.02207-23","article-title":"Nosocomial surveillance of multidrug-resistant Acinetobacter baumannii: a genomic epidemiological study","volume":"12","author":"Duan","year":"2024","journal-title":"Microbiol. Spectr."},{"key":"B12","doi-asserted-by":"publisher","first-page":"575","DOI":"10.1016\/j.ijantimicag.2009.07.006","article-title":"Impact of early appropriate antimicrobial therapy on survival in Acinetobacter baumannii bloodstream infections","volume":"34","author":"Erbay","year":"2009","journal-title":"Int. J. Antimicrob. Agents"},{"key":"B13","doi-asserted-by":"publisher","first-page":"2059","DOI":"10.1093\/cid\/ciad100","article-title":"Mortality attributable to bloodstream infections caused by different carbapenem-resistant gram-negative bacilli: results from a nationwide study in Italy (ALARICO network)","volume":"76","author":"Falcone","year":"2023","journal-title":"Clin. Infect. Dis."},{"key":"B14","doi-asserted-by":"publisher","first-page":"481","DOI":"10.1146\/annurev-micro-020518-115714","article-title":"Acinetobacter baumannii: envelope determinants that control drug resistance, virulence, and surface variability","volume":"73","author":"Geisinger","year":"2019","journal-title":"Annu. Rev. Microbiol."},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2022.983963","article-title":"Molecular epidemiology and carbapenem resistance characteristics of Acinetobacter baumannii causing bloodstream infection from 2009 to 2018 in northwest China","volume":"22","author":"Gu","year":"2022","journal-title":"Front. Microbiol."},{"key":"B16","doi-asserted-by":"publisher","first-page":"S15","DOI":"10.1016\/j.cmi.2015.11.004","article-title":"Laboratory diagnosis, clinical management and infection control of the infections caused by extensively drug-resistant Gram-negative bacilli: a Chinese consensus statement","volume":"22","author":"Guan","year":"2016","journal-title":"ClinMicrobiol Infect."},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1099\/mgen.0.000306","article-title":"Emergence, molecular mechanisms, and global spread of carbapenem-resistant Acinetobacter baumannii","volume":"5","author":"Hamidian","year":"2019","journal-title":"Microb. Genom"},{"key":"B18","doi-asserted-by":"publisher","first-page":"S14","DOI":"10.1016\/j.cmi.2023.09.001","article-title":"A systematic review on the excess health risk of antibiotic-resistant bloodstream infections for six key pathogens in Europe","author":"Hassoun-Kheir","year":"2024","journal-title":"Clin. Microbiol. Infect."},{"key":"B19","doi-asserted-by":"publisher","first-page":"2094","DOI":"10.1080\/22221751.2020.1822757","article-title":"Association of capsular types with carbapenem resistance, disease severity, and mortality in Acinetobacter baumannii","volume":"9","author":"Hsieh","year":"2020","journal-title":"Emerg. Microbes Infect."},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0062160","article-title":"Variation in the complex carbohydrate biosynthesis loci of Acinetobacter baumannii genomes","volume":"8","author":"Kenyon","year":"2013","journal-title":"PloS One"},{"key":"B21","doi-asserted-by":"publisher","first-page":"e01807","DOI":"10.1128\/AAC.01807-21","article-title":"Updated analysis of the surface carbohydrate gene clusters in a diverse panel of Acinetobacter baumannii isolates","volume":"66","author":"Kenyon","year":"2021","journal-title":"Antimicrob. Agents Chemother."},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.02734-21","article-title":"Carbapenem Resistance in Acinetobacter nosocomialis and Acinetobacter junii Conferred by Acquisition of and Genetic Characterization of the Transmission Mechanism between Acinetobacter Genomic Species","volume":"10","author":"Lasarte-Monterrubio","year":"2022","journal-title":"Microbiol. Spectr."},{"key":"B23","doi-asserted-by":"publisher","first-page":"1730","DOI":"10.1080\/22221751.2022.2093134","article-title":"Epidemiological and genetic characteristics of clinical carbapenem-resistant Acinetobacter baumannii strains collected countrywide from hospital intensive care units (ICUs) in China","volume":"11","author":"Liu","year":"2022","journal-title":"Emerg. Microbes Infect."},{"key":"B24","doi-asserted-by":"crossref","first-page":"2365","DOI":"10.3390\/microorganisms9112365","article-title":"Virulence characteristics of biofilm-forming Acinetobacter baumannii in clinical isolates using a Galleria mellonella model","volume":"9","author":"Mahmoud","year":"2021","journal-title":"Microorganisms"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1128\/aac.00298-24","article-title":"Harrison Fontana Acinetobacter baumannii international clone 2 co-producing OXA-23, NDM-1, and ArmA emerging in South America","volume":"68","author":"Martins-Gon\u00e7alves","year":"2024","journal-title":"Antimicrob. Agents Chemother."},{"key":"B26","doi-asserted-by":"publisher","first-page":"106402","DOI":"10.1016\/j.ijantimicag.2021.106402","article-title":"Molecular and epidemiological investigation of a colistin-resistant OXA-23-\/NDM-1-producing Acinetobacter baumannii outbreak in the Southwest Indian Ocean Area","volume":"58","author":"Miltgen","year":"2021","journal-title":"Int. J. Antimicrob. Agents"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2019.01601","article-title":"The mechanisms of disease caused by Acinetobacter baumannii","volume":"10","author":"Morris","year":"2019","journal-title":"Front. Microbiol."},{"key":"B28","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/21505594.2019.1700659","article-title":"Wza gene knockout decreases Acinetobacter baumannii virulence and affects Wzy-dependent capsular polysaccharide synthesis","volume":"11","author":"Niu","year":"2020","journal-title":"Virulence"},{"key":"B29","doi-asserted-by":"publisher","first-page":"391","DOI":"10.1016\/S1473-3099(18)30099-9","article-title":"Colistin alone versus colistin plus meropenem for treatment of severe infections caused by carbapenem-resistant gram-negative bacteria: an open-label, randomized controlled trial","volume":"18","author":"Paul","year":"2018","journal-title":"Lancet Infect. Dis."},{"key":"B30","doi-asserted-by":"publisher","first-page":"188","DOI":"10.1186\/s12887-021-02661-9","article-title":"Epidemiology, risk factors and outcomes of bloodstream infection caused by ESKAPEEc pathogens among hospitalized children","volume":"21","author":"Peng","year":"2021","journal-title":"BMC Pediatr."},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.01044-24","article-title":"RESIST ACINETO test for the rapid detection of NDM and OXA acquired carbapenemases directly from blood culture in Acinetobacter species","author":"Potron","year":"2024","journal-title":"Microbiol. Spectr."},{"key":"B32","doi-asserted-by":"publisher","first-page":"dkae314","DOI":"10.1093\/jac\/dkae314","article-title":"Genome analysis of tigecycline-resistant Acinetobacter baumannii reveals nosocomial lineage shifts and novel resistance mechanisms","author":"Qian","year":"2024","journal-title":"J. Antimicrob. Chemother."},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.03002-22","article-title":"Phenotypic and genomic characterization of nine string-positive carbapenem-resistant acinetobacter baumannii isolates from Israel","volume":"11","author":"Rakovitsky","year":"2023","journal-title":"Microbiol. Spectr."},{"key":"B34","doi-asserted-by":"publisher","first-page":"510","DOI":"10.18502\/ijm.v14i4.10237","article-title":"Investigation the effects of silver nanoparticles and gold nanoparticles on expression of bap and csu genes in biofilm formation of Acinetobacter baumannii","volume":"14","author":"Rezania","year":"2022","journal-title":"Iran J. Microbiol."},{"key":"B35","doi-asserted-by":"publisher","first-page":"ciae403","DOI":"10.1093\/cid\/ciae403","article-title":"Infectious diseases society of america 2024 guidance on the treatment of antimicrobial-resistant gram-negative infections","author":"Tamma","year":"2024","journal-title":"Clin. Infect. Dis."},{"key":"B36","doi-asserted-by":"publisher","first-page":"248","DOI":"10.1093\/cid\/ciad556","article-title":"Clinical outcomes and bacterial characteristics of carbapenem-resistant acinetobacter baumannii among patients from different global regions","volume":"78","author":"Wang","year":"2024","journal-title":"Clin. Infect. Dis."},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.1099\/mgen.0.000339","article-title":"Identification of Acinetobacter baumannii loci for capsular polysaccharide (KL) and lipooligosaccharide outer core (OCL) synthesis in genome assemblies using curated reference databases compatible with Kaptive","volume":"6","author":"Wyres","year":"2022","journal-title":"Microb. Genom"},{"key":"B38","doi-asserted-by":"publisher","first-page":"83","DOI":"10.1080\/22221751.2021.2011624","article-title":"Association of capsular polysaccharide locus 2 with prognosis of Acinetobacter baumannii bacteraemia","volume":"11","author":"Yang","year":"2022","journal-title":"Emerg. Microbes Infect."},{"key":"B39","doi-asserted-by":"publisher","first-page":"16","DOI":"10.1186\/s13756-020-00876-6","article-title":"Bloodstream infections caused by ST2 Acinetobacter baumannii: risk factors, antibiotic regimens, and virulence over 6 years period in China","volume":"10","author":"Yu","year":"2021","journal-title":"Antimicrob. Resist. Infect. Control"},{"key":"B40","doi-asserted-by":"publisher","DOI":"10.1128\/spectrum.01593-21","article-title":"Genomic and phenotypic evolution of tigecycline-resistant acinetobacter baumannii in critically ill patients","volume":"10","author":"Zhang","year":"2022","journal-title":"Microbiol. Spectr."},{"key":"B41","doi-asserted-by":"publisher","DOI":"10.3389\/fpubh.2023.1282413","article-title":"Insights into the epidemiology, risk factors, and clinical outcomes of carbapenem-resistant Acinetobacter baumannii infections in critically ill children","volume":"11","author":"Zhang","year":"2023","journal-title":"Front. Public Health"},{"key":"B42","doi-asserted-by":"publisher","first-page":"45","DOI":"10.1186\/s12941-022-00538-y","article-title":"Incidence, clinical characteristics, risk factors and outcomes of patients with mixed Candida\/bacterial bloodstream infections: a retrospective study","volume":"21","author":"Zhong","year":"2022","journal-title":"Ann. Clin. Microbiol. Antimicrob."}],"updated-by":[{"DOI":"10.3389\/fcimb.2025.1585728","type":"corrigendum","label":"Corrigendum","source":"publisher","updated":{"date-parts":[[2025,3,19]],"date-time":"2025-03-19T00:00:00Z","timestamp":1742342400000}}],"container-title":["Frontiers in Cellular and Infection Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1549940\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,19]],"date-time":"2025-03-19T09:09:04Z","timestamp":1742375344000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1549940\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,17]]},"references-count":42,"alternative-id":["10.3389\/fcimb.2025.1549940"],"URL":"https:\/\/doi.org\/10.3389\/fcimb.2025.1549940","relation":{"corrigendum":[{"id-type":"doi","id":"10.3389\/fcimb.2025.1585728","asserted-by":"object"}]},"ISSN":["2235-2988"],"issn-type":[{"value":"2235-2988","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,17]]},"article-number":"1549940"}}