{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T23:18:58Z","timestamp":1792624738070,"version":"4.5.0"},"reference-count":36,"publisher":"Oxford University Press (OUP)","issue":"6","license":[{"start":{"date-parts":[[2022,4,5]],"date-time":"2022-04-05T00:00:00Z","timestamp":1649116800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,5,29]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>During the COVID-19 pandemic, the burden of nosocomial infections caused by MDR pathogens has caused a shortage of polymyxins. Thus, we evaluated the in vitro synergism and antibiofilm activity of antimicrobial combinations and propose a test kit for synergism against carbapenem-resistant Acinetobacter baumannii (CRAB).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Fifty-six CRAB isolates were tested for synergy between meropenem, gentamicin and ampicillin\/sulbactam. MICs were determined by broth microdilution. Synergism was tested using chequerboard analysis, followed by a time\u2013kill curve. Additionally, minimum biofilm eradication concentration was determined and the antibiofilm activity of the combinations was evaluated by MTT assay and biomass reduction. A test kit was developed for routine laboratory testing to detect synergism.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>All CRAB isolates were resistant to gentamicin and ampicillin\/sulbactam. Chequerboard synergism occurred against 75% of the isolates. Meropenem\u200a+\u200aampicillin\/sulbactam was the most frequent combination with synergism (69%), followed by ampicillin\/sulbactam\u200a+\u200agentamicin (64%) and meropenem\u200a+\u200agentamicin (51%). All combinations presented only bacteriostatic activity and no bactericidal or antibiofilm effects. The routine laboratory test showed 100% accuracy compared with other in vitro assays.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Our study demonstrates the potential role of antibiotic combinations against planktonic bacteria. In vitro synergism is possible and can be an alternative treatment for patients with CRAB infection during a polymyxin shortage.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/jac\/dkac102","type":"journal-article","created":{"date-parts":[[2022,3,17]],"date-time":"2022-03-17T12:13:48Z","timestamp":1647519228000},"page":"1676-1684","source":"Crossref","is-referenced-by-count":21,"title":["A carbapenem-resistant <i>Acinetobacter baumannii<\/i> outbreak associated with a polymyxin shortage during the COVID pandemic: an <i>in vitro<\/i> and biofilm analysis of synergy between meropenem, gentamicin and sulbactam"],"prefix":"10.1093","volume":"77","author":[{"given":"Viviane","family":"Chaiben","sequence":"first","affiliation":[{"name":"Laboratory of Emerging Infectious Diseases, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1 , Curitiba - PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0065-3963","authenticated-orcid":false,"given":"Carolina Hikari","family":"Yamada","sequence":"additional","affiliation":[{"name":"Laboratory of Emerging Infectious Diseases, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1 , Curitiba - PR, Brazil"},{"name":"Hospital Universit\u00e1rio Evang\u00e9lico Mackenzie , Curitiba - PR, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jo\u00e3o Paulo","family":"Telles","sequence":"additional","affiliation":[{"name":"Laboratory of Emerging Infectious Diseases, Pontif\u00edcia Universidade Cat\u00f3lica do Paran\u00e1 , Curitiba - PR, Brazil"},{"name":"Hospital Universit\u00e1rio Evang\u00e9lico Mackenzie , Curitiba - PR, Brazil"},{"name":"AC Camargo Cancer Center, Department of Infectious Diseases , S\u00e3o Paulo - SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana 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