In Vitro Activity of Eravacycline in Combination with Colistin Against Carbapenem-Resistant A. baumannii Isolates

Ozger, H. S.; Cuhadar, T.; Suzuk Yildiz, S.; Demirbas Gulmez, Z.; Dizbay, M.; Guzel Tunccan, O.; Kalkanci, A.; Simsek, H.; Unaldi, O.

doi:10.1101/552547

bioRxiv · 10.1101/552547

In Vitro Activity of Eravacycline in Combination with Colistin Against Carbapenem-Resistant A. baumannii Isolates

Ozger, H. S.·Cuhadar, T.·Suzuk Yildiz, S.·Demirbas Gulmez, Z.·Dizbay, M.·Guzel Tunccan, O.·Kalkanci, A.·Simsek, H.·Unaldi, O.

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Abstract

The synergistic activity of eravacycline in combination with colistin on carbapenem-resistant A.baumannii (CRAB) isolates was evaluated in this study. Minimum inhibitory concentrations (MICs) of eravacycline and colistin were determined by the broth microdilution method. MICs values ranged between 1 to 4 mg and 0,5 to 128 mg/L for eravacycline and colistin, respectively. In-vitro synergy between eravacycline and colistin was evaluated by using the chequerboard methodology. Synergistic activity was found in 10 % of the strains, and additive effect in 20 %. No antagonism was detected. Similar activity was also observed in colistin resistant CRAB isolates. The result of this study indicates that eravacycline and colistin combination may be a potential therapeutic option for the treatment of CRAB related infections.

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Ozger, H. S., Cuhadar, T., Suzuk Yildiz, S., Demirbas Gulmez, Z., Dizbay, M., Guzel Tunccan, O., Kalkanci, A., Simsek, H., Unaldi, O.. 2019-02-19. In Vitro Activity of Eravacycline in Combination with Colistin Against Carbapenem-Resistant A. baumannii Isolates. https://doi.org/10.1101/552547

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