{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T21:02:42Z","timestamp":1788901362024,"version":"build-2803163510"},"reference-count":36,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,14]],"date-time":"2025-11-14T00:00:00Z","timestamp":1763078400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Acinetobacter baumanni (A. baumannii) is a well-known pathogen associated with antimicrobial-resistant infections. It is a major cause of nosocomial infections and is frequently associated with polymicrobial and antibiotic-resistant infections. This study investigates the frequency of A. baumannii infections, its antimicrobial resistance profile and the main co-pathogens isolated in respiratory samples at the San Giovanni di Dio e Ruggi d\u2019Aragona Hospital in 2015\u20132019 (pre-COVID-19 pandemic) and 2020\u20132023 (during\/post-COVID-19 pandemic). Bacterial identification and antibiotic susceptibility testing were performed using the VITEK\u00ae 2 system (2015\u20132019), while identification was carried out with MALDI-TOF MS starting from 2020. A total of 1679 strains were isolated between 2015 and 2019, and 1186 between 2020 and 2023, with significantly higher frequencies in males 61\u201380 and females 71\u201380. A. baumannii was isolated predominantly from respiratory specimens, derived predominantly in intensive care units (ICUs). The antimicrobial resistance rates of A. baumannii were above 90% for gentamicin, trimethoprim\/sulfamethoxazole, imipenem and ciprofloxacin, while colistin resistance was less than 1% (0.95%) in pre-pandemic and alarmingly increased during\/post pandemic period (6.1%). A. baumannii was most frequently associated with Klebsiella pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa in respiratory tract infections. A. baumannii represents a serious global health threat due to its extensive antimicrobial resistance, highlighting the need for continuous surveillance, detailed strain characterization, and development of new antimicrobial agents.<\/jats:p>","DOI":"10.3390\/pathogens14111165","type":"journal-article","created":{"date-parts":[[2025,11,14]],"date-time":"2025-11-14T16:46:22Z","timestamp":1763138782000},"page":"1165","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["A Nine-Year Review of Acinetobacter baumannii Infections Frequency and Antimicrobial Resistance in a Single-Center Study in Salerno, Italy"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6556-0760","authenticated-orcid":false,"given":"Enrica","family":"Serretiello","sequence":"first","affiliation":[{"name":"U.O.S. Microbiology and Virology, AOU San Giovanni di Dio e Ruggi d\u2019Aragona, 84131 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3955-5675","authenticated-orcid":false,"given":"Mariagrazia","family":"De Prisco","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-2074-1291","authenticated-orcid":false,"given":"Giuseppe","family":"Di Siervi","sequence":"additional","affiliation":[{"name":"Postgraduate School in Clinical Pathology and Clinical Biochemistry, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ilaria","family":"Cosimato","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1654-8500","authenticated-orcid":false,"given":"Federica","family":"Dell\u2019Annunziata","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0602-2513","authenticated-orcid":false,"given":"Emanuela","family":"Santoro","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emilia Anna","family":"Vozzella","sequence":"additional","affiliation":[{"name":"University Hospital \u201cSan Giovanni di Dio e Ruggi d\u2019Aragona\u201d, 84121 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7757-6855","authenticated-orcid":false,"given":"Giovanni","family":"Boccia","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"},{"name":"UOC Hospital and Epidemiological Hygiene, San Giovanni di Dio and Ruggi D\u2019Aragona University Hospital, 84131 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7406-9882","authenticated-orcid":false,"given":"Veronica","family":"Folliero","sequence":"additional","affiliation":[{"name":"Department of Medicine, Surgery and Dentistry \u201cScuola Medica Salernitana\u201d, University of Salerno, Baronissi, 84081 Salerno, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3321-4331","authenticated-orcid":false,"given":"Gianluigi","family":"Franci","sequence":"additional","affiliation":[{"name":"U.O.S. 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