Synergy between Florfenicol and Aminoglycosides against Multidrug-Resistant Escherichia coli Isolates from Livestock

Abstract

The increasing prevalence of antimicrobial resistance and the laborious development of novel antimicrobial agents have limited the options for effective antimicrobial therapy. The combination of previously used antimicrobial agents represents an alternative therapy for multidrug-resistant (MDR) pathogens. The objective of this study was to investigate the synergistic effect of a florfenicol (FFL)-based combination with other antimicrobial agents against MDR Escherichia coli isolates from livestock using checkerboard assays and murine infection models. The FFL/amikacin (AMK) and FFL/gentamicin (GEN) combinations showed synergy against 10/11 and 6/11 MDR E. coli isolates in vitro, respectively. The combination of FFL with aminoglycosides (AMK or GEN) exhibited a better synergistic effect against MDR E. coli isolates than the cephalothin (CEF)/GEN or FFL/CEF combinations. The combination of FFL with AMK or GEN could reduce the emergence of resistant mutants in vitro. The FFL/AMK combination showed a higher survival rate of mice infected with MDR E. coli isolates than FFL or AMK alone. In summary, the combination of FFL with aminoglycosides (AMK or GEN) is highly effective against MDR E. coli isolates both in vitro and in vivo. Our findings may contribute to the discovery of an effective combination regimen against MDR E. coli infections in veterinary medicine.

In Vitro and In Vivo Effect of Amikacin and Imipenem Combinations against Multidrug-Resistant E. coli

“…The emergence of bacterial resistance is considered a critical global issue. As infections by bacterial-resistant strains are associated with high morbidity and mortality, the World Health Organization (WHO) lists carbapenem-resistant strains, especially carbapenem-resistant Enterobacteriaceae (CRE), as one of the top tier of antibiotic-resistant “priority pathogens” that are considered as the greatest threat to human health [ 35 , 36 ]. Treatment with antibiotic combinations is recommended in severe infections caused by resistant strains [ 37 , 38 , 39 , 40 ].…”

In vitro assessment of PEG-6000 coated-ZnO nanoparticles: modulating action to the resisted antibiotic activity against APEC

“…2 Avian and Rabbit Medicine Department, Faculty of Veterinary Medicine, Assiut University, Asyut, Egypt. 3 Department of Chemistry, Faculty of Science, Assiut University, Asyut, Egypt. 4 Poultry Diseases Department, Agriculture Research Center, Animal Health Research Institute, Assiut Lab.…”

“…Antibacterial resistance is global, multifaceted phenomenon, common among APEC strains, and forms a major economic burden [ 2 ]. Multiple antimicrobial resistances and the laborious development of novel antimicrobial agents have limited the options for effective antimicrobial therapy [ 3 ]. Most recent studies have called for the necessity of retaining the activity of the available antimicrobials or searching for effective alternatives.…”

MDN-6, a Possible Therapeutic Candidate for Multidrug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis

“…A total of 25 six-week-old female BALB/c mice were purchased for the study and divided into five groups based on the provided treatments: Group-1 (G1) received only vehicle (corn oil), Group-2 (G2) received MDN-6 at 125 mg/kg body weight, Group-3 (G3) received MDN-6 at 250 mg/kg body weight, Group-4 (G4) received MDN-6 at 500 mg/kg body weight, and Group-5 (G5) received MDN-6 at 1000 mg/kg body weight (G5). Finally, the 50% lethal dosage (LD 50 ) was determined by a Questgraph LD 50 calculator (AAT Bioquest Inc., USA) (19).…”