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

DÜNDAR D., Duymaz Z., GENÇ S., ER D. K., İRVEM A., Kandemir N.

JOURNAL OF CHEMOTHERAPY, vol.30, pp.342-347, 2018 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 30
  • Publication Date: 2018
  • Doi Number: 10.1080/1120009x.2018.1516270
  • Journal Name: JOURNAL OF CHEMOTHERAPY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.342-347
  • Keywords: Imipenem, colistin, tigecycline, synergy, Carbapenem-resistant Enterobacteriaceae, KLEBSIELLA-PNEUMONIAE, FOSFOMYCIN, DORIPENEM, THERAPY, SYNERGY
  • Kocaeli University Affiliated: Yes

Abstract

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.