In vitro investigations into the use of antimicrobials in combination to maintain efficacy of fluoroquinolones in poultry.
The aim of this study was to determine if apramycin, colistin or lincomycin-spectinomycin, in combination with enrofloxacin, was able prevent the emergence of mutants with reduced susceptibility to fluoroquinolone antibiotics in vitro. MICs were determined for enrofloxacin alone and in combination for panels of Campylobacter (n=37), Escherichia coli (n=52) and Salmonella (n=52) isolates. MIC results suggested that apramycin, colistin and lincomycin-spectinomycin worked in an additive/indifferent way when each was combined with enrofloxacin. Apramycin was considered the most promising antibiotic for combination-therapy in conjunction with enrofloxacin, and further evaluations (MBCs, MPCs and time-kill-curves) were performed for this combination for selected isolates. Results suggest combination-therapy of enrofloxacin with apramycin increases the efficacy, as well as decreasing the emergence and survival of bacteria with mutational resistance to fluoroquinolone antibiotics. Such combination-therapy, minimising the development of mutational resistance, may have relevance for Campylobacter, E. coli and Salmonella infections in poultry.
Animal and Plant Health Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK. Electronic address: luke.randall@apha.gsi.gov.uk.
Luke
L
Randall
Animal and Plant Health Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Anne
A
Ridley
Animal and Plant Health Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Fabrizio
F
Lemma
Animal and Plant Health Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Carol
C
Hale
Animal and Plant Health Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Rob
R
Davies
D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002167:Campylobacter / Q000187:drug effects; D002169:Campylobacter Infections / Q000188:drug therapy* / Q000382:microbiology; D004338:Drug Combinations; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000382:microbiology; D024841:Fluoroquinolones / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D011201:Poultry Diseases / Q000188:drug therapy* / Q000382:microbiology; D012475:Salmonella / Q000187:drug effects; D012481:Salmonella Infections, Animal / Q000188:drug therapy* / Q000382:microbiology
D000900:Anti-Bacterial Agents; D004338:Drug Combinations; D024841:Fluoroquinolones
Apramycin; Combination-therapy; Fluoroquinolone resistance; Mutant prevention concentration