{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T14:28:13Z","timestamp":1768487293077,"version":"3.49.0"},"reference-count":23,"publisher":"Akademiai Kiado Zrt.","issue":"3","content-domain":{"domain":["akjournals.com"],"crossmark-restriction":true},"short-container-title":["AMicr"],"published-print":{"date-parts":[[2022,9,16]]},"abstract":"Abstract<\/jats:title>\n Treatment of infections caused by OXA-48 carbapenemase producing multidrug-resistant isolates often necessitates combination therapy. In vitro<\/jats:italic> effect of different antibiotic combinations against multidrug-resistant (MDR) Klebsiella pneumoniae<\/jats:italic> isolates were evaluated in this study.<\/jats:p>\n Meropenem-tobramycin (MER+TOB), meropenem-ciprofloxacin (MER+CIP), colistin-meropenem (COL+MER), colistin-ciprofloxacin (COL+CIP) and colistin-tobramycin (COL+TOB) combinations were tested by time kill-assays. Each antibiotic alone and in combination at their Cmax values were tested against 4 clinical K. pneumoniae<\/jats:italic> isolates at 1, 2, 4, 6, 8, 12 and 24\u2009h. Effect of colistin and its associations were also assessed at 30\u2009min. Bactericidal activity was defined as \u22653log10<\/jats:sub>\u2009CFU mL\u22121<\/jats:sup> decrease compared with initial inoculum. Synergy was defined as \u22652log10<\/jats:sub>CFU mL\u22121<\/jats:sup> decrease by the combination compared with the most active single agent. Presence of bla<\/jats:italic>\n OXA-48<\/jats:sub>, bla<\/jats:italic>\n NDM<\/jats:sub>, bla<\/jats:italic>\n VIM<\/jats:sub>, bla<\/jats:italic>\n IMP<\/jats:sub>, bla<\/jats:italic>\n KPC<\/jats:sub> and bla<\/jats:italic>\n CTX-M-1<\/jats:sub> genes was screened by PCR using specific primers.<\/jats:p>\n The bla<\/jats:italic>\n OXA-48<\/jats:sub> gene was identified together with bla<\/jats:italic>\n CTXM-1<\/jats:sub> group gene in all isolates. COL+MER demonstrated to be synergistic and bactericidal. MER+TOB showed synergistic and bactericidal effect on two strains although, regrowth was seen on other two strains at 24\u2009h. MER+CIP exhibited indifferent effect on the strains.<\/jats:p>\n Combination therapy could be a potential alternative to treat MDR K. pneumoniae<\/jats:italic> infections. This combination might prevent resistance development and secondary effects of colistin monotherapy. MER+TOB and MER+CIP might have an isolate-dependent effect, that may not always result in synergism.<\/jats:p>","DOI":"10.1556\/030.2022.01785","type":"journal-article","created":{"date-parts":[[2022,9,16]],"date-time":"2022-09-16T12:49:16Z","timestamp":1663332556000},"page":"215-219","update-policy":"https:\/\/doi.org\/10.1556\/policypage.crossmark.crossref.1","source":"Crossref","is-referenced-by-count":2,"title":["Time kill-assays of antibiotic combinations for multidrug resistant clinical isolates of OXA-48 carbapenemase producing Klebsiella pneumoniae"],"prefix":"10.1556","volume":"69","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5310-313X","authenticated-orcid":true,"given":"Fatma","family":"Erdem","sequence":"first","affiliation":[{"name":"Department of Medical Microbiology, Adana City Training and Research Hospital, Department of Medical Microbiology, Adana, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda","family":"D\u00edez-Aguilar","sequence":"additional","affiliation":[{"name":"Servicio de Microbiolog\u00eda, Hospital Universitario La Princesa, Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lutfiye","family":"Oksuz","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cigdem","family":"Kayacan","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Faculty of Medicine, Istanbul Ayd\u0131n University, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ayham","family":"Abulaila","sequence":"additional","affiliation":[{"name":"Department of Clinical Microbiology, Istinye Faculty of Medicine, Istinye University, Istanbul, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oral","family":"Oncul","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases and Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Turkey"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda Isabel","family":"Morosini","sequence":"additional","affiliation":[{"name":"Servicio de Microbiolog\u00eda. 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J Clin Med \n 2019; 8(7): 934.10.3390\/jcm8070934"},{"issue":"11","key":"B22","series-title":"Viruses","doi-asserted-by":"publisher","DOI":"10.3390\/v11111080","article-title":"Characterization of Klebsiella pneumoniae ST11 isolates and their interactions with lytic phages","volume":"11","author":"Tan \n D","year":"2019","unstructured":"Tan \n D\n , \n Zhang \n Y\n , \n Cheng \n M\n , \n Le \n S\n , \n Gu \n J\n , \n Bao \n J\n , et\u00a0al.\n \n Characterization of Klebsiella pneumoniae ST11 isolates and their interactions with lytic phages. Viruses \n 2019; 11(11).10.3390\/v11111080"},{"key":"B23","series-title":"J Glob Antimicrob Res","first-page":"127","article-title":"Prospective, comparative clinical study between high-dose colistin monotherapy and colistin-meropenem combination therapy for treatment of hospital-acquired pneumonia and ventilator-associated pneumonia caused by multidrug-resistant Klebsiella pneumoniae","volume":"15","author":"Abdelsalam \n MFA","year":"2018","unstructured":"Abdelsalam \n MFA\n , \n Abdalla \n MS\n , \n El-Abhar \n HSE\n \n . Prospective, comparative clinical study between high-dose colistin monotherapy and colistin-meropenem combination therapy for treatment of hospital-acquired pneumonia and ventilator-associated pneumonia caused by multidrug-resistant Klebsiella pneumoniae\n . J Glob Antimicrob Res \n 2018; 15: 127\u201335."}],"container-title":["Acta Microbiologica et Immunologica Hungarica"],"original-title":[],"link":[{"URL":"https:\/\/akjournals.com\/view\/journals\/030\/69\/3\/article-p215.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/akjournals.com\/downloadpdf\/journals\/030\/69\/3\/article-p215.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/akjournals.com\/downloadpdf\/journals\/030\/69\/3\/article-p215.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,9,16]],"date-time":"2022-09-16T12:55:11Z","timestamp":1663332911000},"score":1,"resource":{"primary":{"URL":"https:\/\/akjournals.com\/view\/journals\/030\/69\/3\/article-p215.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9,16]]},"references-count":23,"journal-issue":{"issue":"3"},"URL":"https:\/\/doi.org\/10.1556\/030.2022.01785","relation":{},"ISSN":["1217-8950","1588-2640"],"issn-type":[{"value":"1217-8950","type":"print"},{"value":"1588-2640","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,9,16]]}}}