{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T20:40:08Z","timestamp":1792615208884,"version":"4.5.0"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: The coronavirus disease 2019 (COVID-19) pandemic coincided with substantial changes in healthcare delivery and antimicrobial resistance (AMR) patterns worldwide, particularly in intensive care units (ICUs), where invasive procedures and broad-spectrum antibiotics are commonly used. Data from T\u00fcrkiye remains limited. Methods: This retrospective observational study evaluated bacterial and fungal isolates from adult ICU patients at a tertiary hospital from 2016 to 2025. Microorganisms were identified, and antimicrobial susceptibility testing was performed using standardized methods. Resistance patterns were compared between the pre-pandemic (January 2016\u2013February 2020) and post-pandemic (March 2020\u2013May 2025) periods. Results: A total of 2666 patients and 5433 isolates were analyzed. Gram-negative pathogens showed marked increases in resistance: carbapenem and colistin resistance in Klebsiella pneumoniae were significantly higher in the post-pandemic period (69.6% vs. 44.4% and 60.5% vs. 22.5%, respectively; p &lt; 0.001). Resistance rates to multiple antimicrobial agents also increased in Acinetobacter baumannii and Pseudomonas aeruginosa (p &lt; 0.05). Among Gram-positive bacteria, vancomycin-resistant Enterococcus faecium increased from 10% to 47.1%. Candida auris emerged only in the post-pandemic period, showing high resistance to fluconazole (75%) and amphotericin B (36.7%). Conclusions: Significant differences in AMR patterns were observed between the pre- and post-pandemic periods in this ICU population. Higher resistance rates were observed among several clinically important bacterial pathogens, and Candida auris emerged exclusively during the post-pandemic period. Given the study\u2019s observational design, these findings should be interpreted as temporal associations rather than evidence of a causal effect of the COVID-19 pandemic. Continued antimicrobial stewardship and infection-control measures remain essential to address the growing burden of AMR.<\/jats:p>","DOI":"10.3390\/antibiotics15070636","type":"journal-article","created":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T10:04:47Z","timestamp":1783418687000},"page":"636","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Changes in Antimicrobial Resistance Patterns in Intensive Care Units Following the COVID-19 Pandemic: A 10-Year Retrospective Study from T\u00fcrkiye"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6485-342X","authenticated-orcid":false,"given":"Ay\u015fe","family":"\u00c7apar","sequence":"first","affiliation":[{"name":"Anaesthesiology and Intensive Care Medicine, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Derya","family":"\u00d6zyi\u011fito\u011flu","sequence":"additional","affiliation":[{"name":"Infectious Diseases and Clinical Microbiology, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1495-6508","authenticated-orcid":false,"given":"\u015eeyma","family":"Ba\u015fl\u0131lar","sequence":"additional","affiliation":[{"name":"Chest Diseases, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-3959-3155","authenticated-orcid":false,"given":"M\u00fcr\u015fide","family":"Efil Erdo\u011fan","sequence":"additional","affiliation":[{"name":"Pulmonary Intensive Care Unit, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1983-9757","authenticated-orcid":false,"given":"Beril","family":"Balak","sequence":"additional","affiliation":[{"name":"General Practice, Chelsea and Westminster Hospital, London SW10 9NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bet\u00fcl Nur","family":"Do\u011fan","sequence":"additional","affiliation":[{"name":"Cardiothoracic Surgery Intensive Care Unit, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London W12 0HS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u00d6znur","family":"Hun Akta\u015f","sequence":"additional","affiliation":[{"name":"Chest Diseases, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ebru","family":"Korkmaz","sequence":"additional","affiliation":[{"name":"Chest Diseases, Sultan Abdulhamid Han Training and Research Hospital, 34668 Istanbul, T\u00fcrkiye"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lippi, G., and Sanchis-Gomar, F. 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