{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T08:03:11Z","timestamp":1779696191275,"version":"3.53.1"},"reference-count":19,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Complicated community-acquired pneumonia (cCAP) remains a major cause of morbidity in children. Although pneumococcal conjugate vaccines (PCVs) have reduced invasive disease, severe complications such as empyema and lung abscess persist. A retrospective analysis was conducted on 69 children treated at the University Children\u2019s Hospital Belgrade between 2019 and 2024. Data included demographic characteristics, pneumococcal vaccination status, and radiologically confirmed complications. Patients were classified by residence and vaccination status. Statistical analysis included chi-square (\u03c72) tests, odds ratios (ORs) with 95% confidence intervals, and multivariable logistic regression. Pleuropneumonia and pleural effusion were the most frequent complications, while empyema and lung abscess were the most severe. Both occurred significantly more often in unvaccinated children (p = 0.0054 and p = 0.0027). Multivariable analysis confirmed vaccination as an independent protective factor against empyema (adjusted OR = 0.19, 95% CI 0.06\u20130.61). No significant regional differences were observed after accounting for vaccination status. Vaccination showed a strong protective effect against empyema and lung abscess (OR = 0.24 and 0.04, respectively). Unvaccinated children had significantly longer hospital stays, indicating a more severe clinical course. Prolonged hospitalization was associated with intensified antibiotic therapy, reflecting underlying disease severity. Lack of pneumococcal vaccination is strongly associated with severe complications in children with cCAP. Maintaining high PCV coverage remains essential, alongside early recognition and timely management of pleural disease.<\/jats:p>","DOI":"10.3390\/life16050858","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T06:42:18Z","timestamp":1779691338000},"page":"858","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Impact of Pneumococcal Vaccination on the Occurrence of Complicated Pneumonia in Children: A Retrospective Analysis"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5806-9284","authenticated-orcid":false,"given":"Katarina","family":"Milosevic","sequence":"first","affiliation":[{"name":"Department of Allergology and Immunology, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"},{"name":"Faculty of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8663-9010","authenticated-orcid":false,"given":"Jasna","family":"Kalanj","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia"},{"name":"Department of Pediatric and Neonatal Intensive Care, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-2682-2984","authenticated-orcid":false,"given":"Nadja","family":"Cukanovic","sequence":"additional","affiliation":[{"name":"Department of Pediatric and Neonatal Intensive Care, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-0912-6747","authenticated-orcid":false,"given":"Luka","family":"Zekovic","sequence":"additional","affiliation":[{"name":"Department of Pediatric and Neonatal Intensive Care, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-7766-1208","authenticated-orcid":false,"given":"Vesna","family":"Selakovic","sequence":"additional","affiliation":[{"name":"Department of Pediatric and Neonatal Intensive Care, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9987-057X","authenticated-orcid":false,"given":"Snezana","family":"Rsovac","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Belgrade, Dr Subotica 8, 11000 Belgrade, Serbia"},{"name":"Department of Pediatric and Neonatal Intensive Care, University Children\u2019s Hospital, Tirsova 10, 11000 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1016\/S0140-6736(20)31550-6","article-title":"Complicated pneumonia in children","volume":"396","author":"Kerem","year":"2020","journal-title":"Lancet"},{"key":"ref_2","unstructured":"Centers for Disease Control and Prevention (CDC) (2024). 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Soc."}],"container-title":["Life"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/5\/858\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T07:11:51Z","timestamp":1779693111000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-1729\/16\/5\/858"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,21]]},"references-count":19,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["life16050858"],"URL":"https:\/\/doi.org\/10.3390\/life16050858","relation":{},"ISSN":["2075-1729"],"issn-type":[{"value":"2075-1729","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,21]]}}}