{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,8,22]],"date-time":"2025-08-22T02:41:18Z","timestamp":1755830478031,"version":"3.44.0"},"reference-count":25,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T00:00:00Z","timestamp":1755734400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2022R1F1A1069623"],"award-info":[{"award-number":["2022R1F1A1069623"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Chonnam National University Hospital Biomedical Research Institute","award":["BCRI22033"],"award-info":[{"award-number":["BCRI22033"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Bacterial co-infection has been associated with adverse outcomes in patients with COVID-19. <jats:italic><jats:italic>Streptococcus pneumoniae<\/jats:italic><\/jats:italic> is a common cause of community-acquired pneumonia and may contribute to poor clinical outcomes when co-detected in COVID-19 patients. This study aimed to investigate the clinical significance of pneumococcal positivity in hospitalized patients with COVID-19.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>We conducted a retrospective analysis of adult patients hospitalized with COVID-19 at two tertiary care centers. Pneumococcal positivity was defined by either a positive urinary antigen test or multiplex real-time polymerase chain reaction. Disease severity of COVID-19 pneumonia was assessed using the pneumonia severity index and CURB-65 scoring systems. Propensity score matching and multivariable logistic regression were used to adjust for confounders and identify independent risk factors for mortality.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>Among 280 patients, 65 pneumococcus-positive patients were matched with 65 pneumococcus-negative patients after propensity score matching. In the overall matched cohort, pneumococcal positivity was not significantly associated with in-hospital mortality. However, in patients with severe disease (n\u2009=\u2009156), defined as pneumonia severity index &gt;130 or CURB-65\u2009\u2265\u20093, mortality was significantly higher in pneumococcus-positive patients (n\u2009=\u200939) than in pneumococcus-negative patients (53.8% vs. 29.1%, <jats:italic><jats:italic>p<\/jats:italic><\/jats:italic>\u2009=\u20090.009). In the multivariable analysis of this subgroup, pneumococcal positivity (odds ratio, 4.050; 95% confidence interval, 1.285\u201312.765; <jats:italic><jats:italic>p<\/jats:italic><\/jats:italic>\u2009=\u20090.017) and high-flow oxygen therapy (odds ratio, 6.510; 95% confidence interval, 1.847\u201322.944; <jats:italic><jats:italic>p<\/jats:italic><\/jats:italic>\u2009=\u20090.004) were independently associated with mortality.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusion<\/jats:title>\n<jats:p>Detection of <jats:italic><jats:italic>S. pneumoniae<\/jats:italic><\/jats:italic> by urinary antigen test or multiplex polymerase chain reaction was associated with increased mortality in patients hospitalized with severe COVID-19.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0329474","type":"journal-article","created":{"date-parts":[[2025,8,21]],"date-time":"2025-08-21T17:49:46Z","timestamp":1755798586000},"page":"e0329474","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["The influence of pneumococcal positivity on clinical outcomes among patients hospitalized with COVID-19: A retrospective cohort 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