In-vitro activities of imipenem–colistin, imipenem–tigecycline, and tigecycline–colistin combinations against carbapenem-resistant Enterobacteriaceae*


DÜNDAR D., Duymaz Z., Genc S. , ER D. K. , İrvem A., Kandemir N.

Journal of Chemotherapy, vol.30, no.6-8, pp.342-347, 2018 (Journal Indexed in SCI Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 30 Issue: 6-8
  • Publication Date: 2018
  • Doi Number: 10.1080/1120009x.2018.1516270
  • Title of Journal : Journal of Chemotherapy
  • Page Numbers: pp.342-347
  • Keywords: Carbapenem-resistant Enterobacteriaceae, colistin, Imipenem, synergy, tigecycline

Abstract

© 2018, © 2018 Edizioni Scientifiche per l'Informazione su Farmaci e Terapia.The aim of the study is to determine in-vitro effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin against carbapenem-resistant Enterobacteriaceae (CRE) isolates. A total of 25 CRE isolates were included to the study. The minimum inhibition concentrations of imipenem, colistin-sulphate and tigecycline were determined with broth dilution method. Synergistic effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin were investigated by microdilution checkerboard technique. All of the isolates were resistant to imipenem, whereas 25% of the isolates were resistant to colistin and tigecycline. Imipenem–colistin, imipenem–tigecycline and tigecycline–colistin combinations were synergistic against 40% (10/25), 24% (6/25), and 36% (9/25) of the isolates, respectively. Antagonism was observed in 8% (2/25) of the isolates in tigecycline–colistin combination. Tigecycline–colistin was the most effective (70% synergy) combination in Klebsiella spp. strains; whereas imipenem–colistin was the most effective (75% synergy) combination in Escherichia coli strains. Synergistic effect was variable and strain-depended against CRE isolates that have been tested.