{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T20:07:39Z","timestamp":1790453259710,"version":"4.1.0"},"reference-count":31,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T00:00:00Z","timestamp":1745366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Samsung Medical Center","award":["SMX1230761"],"award-info":[{"award-number":["SMX1230761"]}]},{"name":"Samsung Medical Center","award":["RS-2023-00242888"],"award-info":[{"award-number":["RS-2023-00242888"]}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["SMX1230761"],"award-info":[{"award-number":["SMX1230761"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2023-00242888"],"award-info":[{"award-number":["RS-2023-00242888"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Staphylococcus aureus biofilms complicate the treatment of device-related infections. We hypothesized that combining rifampin with fluoroquinolones could eradicate biofilms even in antimicrobial-resistant S. aureus strains. We determined the synergistic interactions of these combinations in a biofilm model. Thirty methicillin-resistant S. aureus (MRSA) isolates with varying susceptibility profiles were evaluated. Minimum biofilm eradication concentrations (MBECs) were determined using the Calgary Biofilm Device, and the synergy was assessed using the fractional biofilm eradication concentration (FBEC) index. Scanning electron microscopy (SEM) was performed on one strain, and confocal laser scanning microscopy (CLSM) was conducted on four strains for visualizing and evaluating the biofilm viability. The MBEC90 for rifampin and levofloxacin were 512 mg\/L and 256 mg\/L, respectively, and exceeded 1024 mg\/L for ciprofloxacin. Synergy was observed in 56.7% of strains for both the rifampin + ciprofloxacin and rifampin + levofloxacin combinations, with no difference between the combinations. A higher ciprofloxacin MBEC (\u226516 mg\/L) increased the likelihood of synergy with rifampin by 18-fold. SEM and CLSM analyses in a subset of strains confirmed the enhanced biofilm disruption with rifampin + ciprofloxacin compared to ciprofloxacin alone. Our findings suggest that rifampin combined with ciprofloxacin or levofloxacin may synergistically eradicate MRSA biofilms, offering a potential treatment option for device-related infections when alternatives are limited.<\/jats:p>","DOI":"10.3390\/pathogens14050404","type":"journal-article","created":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T10:40:48Z","timestamp":1745404848000},"page":"404","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Enhanced Biofilm Disruption in Methicillin-Resistant Staphylococcus aureus Using Rifampin and Fluoroquinolone Combinations"],"prefix":"10.3390","volume":"14","author":[{"given":"Yu Ri","family":"Kang","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"},{"name":"Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06367, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2121-5997","authenticated-orcid":false,"given":"Joo-Young","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Data Science, School of Software Convergence, Myongji University, Seoul 03674, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Doo Ryeon","family":"Chung","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"},{"name":"Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06367, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minhee","family":"Kang","sequence":"additional","affiliation":[{"name":"Biomedical Engineering Research Center, Smart Healthcare Research Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jae-Hoon","family":"Ko","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyungmin","family":"Huh","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"},{"name":"Asia Pacific Foundation for Infectious Diseases (APFID), Seoul 06367, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sun Young","family":"Cho","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheol-In","family":"Kang","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7464-9780","authenticated-orcid":false,"given":"Kyong Ran","family":"Peck","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,23]]},"reference":[{"key":"ref_1","first-page":"207","article-title":"Staphylococcal biofilms","volume":"322","author":"Otto","year":"2008","journal-title":"Curr. 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