{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T18:09:01Z","timestamp":1781114941006,"version":"3.54.1"},"reference-count":26,"publisher":"Public Library of Science (PLoS)","issue":"6","license":[{"start":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T00:00:00Z","timestamp":1781049600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>\n                    Sputum culture is essential for identifying pneumonia pathogens, but its sensitivity remains limited. This study evaluated the clinical utility of repeated sputum cultures and factors associated with detecting additional significant isolates in subsequent cultures. We retrospectively analyzed adult patients with pneumonia who underwent three serial sputum cultures at a tertiary hospital between January 2021 and December 2022. We excluded patients with over 48 h interval between each sputum sample or those with coronavirus disease 2019. Initial and subsequent culture results were compared, and clinical factors associated with detecting additional significant isolates were evaluated. A total of 132 patients were included. Sputum quality (p\u2009=\u20090.71) and culture positivity rates (p\u2009=\u20090.25) were similar across serial cultures. Fungi, particularly\n                    <jats:italic>Candida<\/jats:italic>\n                    species, were more frequently isolated from subsequent cultures (p\u2009=\u20090.02). The cumulative detection rate of significant isolates did not improve, although the cumulative number was higher in third than initial cultures (p\u2009=\u20090.01). Hypertension, inappropriate empirical antibiotics, shorter intervals to repeat culture, and greater pneumonia severity were independent risk factors for detecting additional significant isolates. Serial sputum cultures provided limited additional diagnostic information and were not associated with meaningful improvement in the sputum quality, culture positivity, or cumulative detection of significant isolates.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0351167","type":"journal-article","created":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T17:34:53Z","timestamp":1781112893000},"page":"e0351167","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical usefulness of repeated sputum culture for the identification of pneumonia pathogens: A retrospective study"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5263-5639","authenticated-orcid":true,"given":"Ji Hyun","family":"Yun","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiho","family":"Park","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun Kyun","family":"Ki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,6,10]]},"reference":[{"issue":"44","key":"pone.0351167.ref001","article-title":"Disease burden of hospitalized community-acquired pneumonia in South Korea: analysis based on age and underlying medical conditions","volume":"96","author":"MJ Choi","year":"2017","journal-title":"Medicine (Baltimore)"},{"key":"pone.0351167.ref002","doi-asserted-by":"crossref","DOI":"10.1164\/rccm.201908-1581ST","article-title":"Diagnosis and treatment of adults with community-acquired pneumonia","volume":"200","author":"JP Metlay","year":"2019","journal-title":"Am J Respir Crit Care Med"},{"issue":"2","key":"pone.0351167.ref003","doi-asserted-by":"crossref","first-page":"160","DOI":"10.3947\/ic.2018.50.2.160","article-title":"Guideline for antibiotic use in adults with community-acquired pneumonia","volume":"50","author":"MS Lee","year":"2018","journal-title":"Infect Chemother"},{"issue":"49","key":"pone.0351167.ref004","article-title":"Epidemiology and clinical characteristics of community-acquired pneumonia in hospitalized patients at a single tertiary center in Korea","volume":"40","author":"KR Ju","year":"2025","journal-title":"J Korean Med Sci"},{"issue":"3","key":"pone.0351167.ref005","doi-asserted-by":"crossref","first-page":"499","DOI":"10.1093\/cid\/ciz876","article-title":"Sputum gram stain for bacterial pathogen diagnosis in community-acquired pneumonia: a systematic review and bayesian meta-analysis of diagnostic accuracy and yield","volume":"71","author":"H Ogawa","year":"2020","journal-title":"Clin Infect Dis"},{"issue":"4","key":"pone.0351167.ref006","doi-asserted-by":"crossref","first-page":"351","DOI":"10.3947\/ic.2013.45.4.351","article-title":"Diagnosis of pneumococcal pneumonia: current pitfalls and the way forward","volume":"45","author":"JY Song","year":"2013","journal-title":"Infect Chemother"},{"issue":"12","key":"pone.0351167.ref007","doi-asserted-by":"crossref","first-page":"1782","DOI":"10.1093\/cid\/ciu140","article-title":"The yield of sputum culture in bacteremic pneumococcal pneumonia after initiation of antibiotics","volume":"58","author":"MS Abers","year":"2014","journal-title":"Clin Infect Dis"},{"issue":"4","key":"pone.0351167.ref008","doi-asserted-by":"crossref","DOI":"10.1128\/cmr.00015-22","article-title":"The microbial etiology of community-acquired pneumonia in adults: from classical bacteriology to host transcriptional signatures","volume":"35","author":"NJ Gadsby","year":"2022","journal-title":"Clin Microbiol Rev"},{"issue":"8","key":"pone.0351167.ref009","doi-asserted-by":"crossref","first-page":"1609","DOI":"10.1007\/s10096-021-04195-5","article-title":"Multinational evaluation of the BioFire\u00ae FilmArray\u00ae Pneumonia plus Panel as compared to standard of care testing","volume":"40","author":"and the EME Evaluation Program Collaborative","year":"2021","journal-title":"Eur J Clin Microbiol Infect Dis"},{"issue":"1","key":"pone.0351167.ref010","doi-asserted-by":"crossref","first-page":"95","DOI":"10.3390\/antibiotics13010095","article-title":"Impact of multiplex PCR in the therapeutic management of severe bacterial pneumonia","volume":"13","author":"J Dessajan","year":"2024","journal-title":"Antibiotics (Basel)"},{"issue":"6","key":"pone.0351167.ref011","doi-asserted-by":"crossref","DOI":"10.1093\/ofid\/ofae253","article-title":"Second time\u2019s the charm? 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