{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T09:20:57Z","timestamp":1785489657882,"version":"3.56.0"},"reference-count":26,"publisher":"Public Library of Science (PLoS)","issue":"7","license":[{"start":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T00:00:00Z","timestamp":1657670400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"King Saud University, Riyadh, Saudi Arabia","award":["researchers supporting project number (RSP2022R494)"],"award-info":[{"award-number":["researchers supporting project number (RSP2022R494)"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Emerging resistance to colistin in <jats:italic>Acinetobacter baumannii<\/jats:italic> clinical strains is concerning because of the limited therapeutic choices for these important clinical pathogens. We studied the <jats:italic>in vitro<\/jats:italic> activities of different colistin-based antimicrobial agent combinations against colistin-resistant <jats:italic>Acinetobacter baumannii<\/jats:italic>. Fourteen clinical isolates of colistin-resistant <jats:italic>Acinetobacter baumannii<\/jats:italic> were obtained between 2015 and 2016. To identify colistin-based combinations with synergistic activities, multiple two antimicrobial combinations based on 8 commercially available drugs were evaluated by the checkerboard method. The most effective colistin-based combinations were vancomycin, aztreonam, ceftazidime and imipenem which showed synergistic activities against all examined strains. Colistin-rifampin showed synergy against four strains. Colistin-tigecycline and colistin-amikacin mostly showed indifferent results. By using the checkerboard tests, we were able to find the most promising colistin-based combinations that may provide more therapeutic options against colistin-resistant <jats:italic>Acinetobacter baumannii<\/jats:italic>.<\/jats:p>","DOI":"10.1371\/journal.pone.0270908","type":"journal-article","created":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T17:37:10Z","timestamp":1657733830000},"page":"e0270908","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":29,"title":["Synergistic activities of colistin combined with other antimicrobial agents against colistin-resistant Acinetobacter baumannii clinical isolates"],"prefix":"10.1371","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9746-4765","authenticated-orcid":true,"given":"Mashal M.","family":"Almutairi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2022,7,13]]},"reference":[{"issue":"1","key":"pone.0270908.ref001","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1007\/s00284-021-02693-5","article-title":"Can Drug Repurposing be Effective Against Carbapenem-Resistant Acinetobacter baumannii?","volume":"79","author":"AVL Gontijo","year":"2021","journal-title":"Curr Microbiol"},{"issue":"11","key":"pone.0270908.ref002","article-title":"Systematic Review of Antimicrobial Combination Options for Pandrug-Resistant Acinetobacter baumannii.","volume":"10","author":"S Karakonstantis","year":"2021","journal-title":"Antibiotics (Basel)."},{"issue":"1","key":"pone.0270908.ref003","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1097\/QCO.0000000000000518","article-title":"Managing Acinetobacter baumannii infections.","volume":"32","author":"J Garnacho-Montero","year":"2019","journal-title":"Curr Opin Infect Dis"},{"issue":"1","key":"pone.0270908.ref004","doi-asserted-by":"crossref","first-page":"97","DOI":"10.3201\/eid1301.060716","article-title":"Multidrug-resistant Acinetobacter infection mortality rate and length of hospitalization","volume":"13","author":"RH Sunenshine","year":"2007","journal-title":"Emerg Infect Dis"},{"issue":"10","key":"pone.0270908.ref005","doi-asserted-by":"crossref","first-page":"949","DOI":"10.1002\/phar.1636","article-title":"Infections Caused by Resistant Gram-Negative Bacteria: Epidemiology and Management.","volume":"35","author":"KS Kaye","year":"2015","journal-title":"Pharmacotherapy"},{"issue":"3","key":"pone.0270908.ref006","article-title":"Insights into Acinetobacter baumannii: A Review of Microbiological, Virulence, and Resistance Traits in a Threatening Nosocomial Pathogen.","volume":"9","author":"CA Moubareck","year":"2020","journal-title":"Antibiotics-Basel."},{"issue":"4","key":"pone.0270908.ref007","doi-asserted-by":"crossref","DOI":"10.1128\/mBio.01083-19","article-title":"Dissecting Colistin Resistance Mechanisms in Extensively Drug-Resistant Acinetobacter baumannii Clinical Isolates.","volume":"10","author":"V Trebosc","year":"2019","journal-title":"mBio"},{"issue":"9","key":"pone.0270908.ref008","doi-asserted-by":"crossref","first-page":"1295","DOI":"10.1093\/cid\/civ048","article-title":"Colistin-resistant Acinetobacter baumannii: beyond carbapenem resistance","volume":"60","author":"ZA Qureshi","year":"2015","journal-title":"Clin Infect Dis"},{"issue":"11","key":"pone.0270908.ref009","doi-asserted-by":"crossref","first-page":"e0207588","DOI":"10.1371\/journal.pone.0207588","article-title":"Risk factors of colistin safety according to administration routes: Intravenous and aerosolized colistin.","volume":"13","author":"KL Min","year":"2018","journal-title":"PLoS One."},{"issue":"12","key":"pone.0270908.ref010","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1086\/599225","article-title":"Nephrotoxicity associated with intravenous colistin (colistimethate sodium) treatment at a tertiary care medical center.","volume":"48","author":"JD Hartzell","year":"2009","journal-title":"Clin Infect Dis"},{"issue":"8","key":"pone.0270908.ref011","doi-asserted-by":"crossref","DOI":"10.1128\/AAC.00779-19","article-title":"Evaluation of the Synergy of Ceftazidime-Avibactam in Combination with Meropenem, Amikacin, Aztreonam, Colistin, or Fosfomycin against Well-Characterized Multidrug-Resistant Klebsiella pneumoniae and Pseudomonas aeruginosa","volume":"63","author":"S Mikhail","year":"2019","journal-title":"Antimicrob Agents Chemother"},{"issue":"2","key":"pone.0270908.ref012","first-page":"Doc14","article-title":"In vitro synergism of combinations of colistin with selected antibiotics against colistin-resistant Acinetobacter baumannii.","volume":"9","author":"D Percin","year":"2014","journal-title":"GMS Hyg Infect Control."},{"key":"pone.0270908.ref013","doi-asserted-by":"crossref","first-page":"63","DOI":"10.2174\/1874285801711010063","article-title":"Synergistic Effect of Colistin and Rifampin Against Multidrug Resistant Acinetobacter baumannii: A Systematic Review and Meta-Analysis.","volume":"11","author":"M Mohammadi","year":"2017","journal-title":"Open Microbiol J."},{"issue":"11","key":"pone.0270908.ref014","doi-asserted-by":"crossref","first-page":"4678","DOI":"10.1128\/AAC.00497-10","article-title":"Synergy testing by Etest, microdilution checkerboard, and time-kill methods for pan-drug-resistant Acinetobacter baumannii","volume":"54","author":"MM Sopirala","year":"2010","journal-title":"Antimicrob Agents Chemother"},{"issue":"2","key":"pone.0270908.ref015","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1016\/j.diagmicrobio.2008.11.002","article-title":"The detection of synergy between meropenem and polymyxin B against meropenem-resistant Acinetobacter baumannii using Etest and time-kill assay","volume":"63","author":"GA Pankey","year":"2009","journal-title":"Diagn Microbiol Infect Dis"},{"issue":"6","key":"pone.0270908.ref016","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1016\/j.ijantimicag.2007.07.007","article-title":"Comparative activities of colistin, rifampicin, imipenem and sulbactam\/ampicillin alone or in combination against epidemic multidrug-resistant Acinetobacter baumannii isolates producing OXA-58 carbapenemases.","volume":"30","author":"MF Tripodi","year":"2007","journal-title":"Int J Antimicrob Agents"},{"issue":"3","key":"pone.0270908.ref017","first-page":"8","article-title":"Extracellular Synthesis, Characterization and Antibacterial Activity of Silver Nanoparticles by a Potent Isolate Streptomyces sp. DW102.","volume":"8","author":"AIAAR Gouse Basha Sheik","year":"2019","journal-title":"Asian Journal of Biological and Life Sciences"},{"key":"pone.0270908.ref018","volume-title":"Performance Standards for Antimicrobial Susceptibility Testing","author":"Institute tCaLS","year":"2021","edition":"31"},{"issue":"11","key":"pone.0270908.ref019","doi-asserted-by":"crossref","first-page":"1147","DOI":"10.1111\/j.1469-0691.2006.01578.x","article-title":"EUCAST technical note on tigecycline.","volume":"12","author":"European Committee on Antimicrobial Susceptibility Testing Steering C.","year":"2006","journal-title":"Clin Microbiol Infect"},{"issue":"2","key":"pone.0270908.ref020","doi-asserted-by":"crossref","first-page":"659","DOI":"10.2466\/pr0.1978.43.2.659","article-title":"Sex differences in psychological distress and social functioning.","volume":"43","author":"B Justice","year":"1978","journal-title":"Psychol Rep"},{"issue":"4","key":"pone.0270908.ref021","doi-asserted-by":"crossref","first-page":"744","DOI":"10.1128\/AAC.42.4.744","article-title":"Use of pharmacodynamic parameters to predict efficacy of combination therapy by using fractional inhibitory concentration kinetics.","volume":"42","author":"JG den Hollander","year":"1998","journal-title":"Antimicrob Agents Ch"},{"issue":"11","key":"pone.0270908.ref022","doi-asserted-by":"crossref","first-page":"6774","DOI":"10.1128\/AAC.00839-16","article-title":"In Vitro Synergistic Activity of Antimicrobial Agents in Combination against Clinical Isolates of Colistin-Resistant Acinetobacter baumannii","volume":"60","author":"Seongman Bae","year":"2016","journal-title":"Antimicrob Agents Chemother"},{"issue":"5","key":"pone.0270908.ref023","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1086\/520658","article-title":"Antibiograms of multidrug-resistant clinical Acinetobacter baumannii: promising therapeutic options for treatment of infection with colistin-resistant strains","volume":"45","author":"J Li","year":"2007","journal-title":"Clin Infect Dis"},{"issue":"7","key":"pone.0270908.ref024","doi-asserted-by":"crossref","first-page":"1607","DOI":"10.1093\/jac\/dks084","article-title":"Colistin resistance of Acinetobacter baumannii: clinical reports, mechanisms and antimicrobial strategies.","volume":"67","author":"Y Cai","year":"2012","journal-title":"J Antimicrob Chemoth"},{"issue":"5","key":"pone.0270908.ref025","doi-asserted-by":"crossref","first-page":"2103","DOI":"10.1128\/AAC.02501-12","article-title":"Activities of Vancomycin-Containing Regimens against Colistin-Resistant Acinetobacter baumannii Clinical Strains.","volume":"57","author":"JA O\u2019Hara","year":"2013","journal-title":"Antimicrob Agents Ch."},{"issue":"7","key":"pone.0270908.ref026","doi-asserted-by":"crossref","first-page":"3534","DOI":"10.1128\/AAC.00230-11","article-title":"In vivo efficacy of glycopeptide-colistin combination therapies in a Galleria mellonella model of Acinetobacter baumannii infection","volume":"55","author":"M Hornsey","year":"2011","journal-title":"Antimicrob Agents Chemother"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0270908","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T17:37:39Z","timestamp":1657733859000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0270908"}},"subtitle":[],"editor":[{"given":"Saeed","family":"El-Ashram","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2022,7,13]]},"references-count":26,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2022,7,13]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0270908","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,7,13]]}}}