title: Susceptibility of canine and feline bacterial pathogens to pradofloxacin and comparison with other fluoroquinolones approved for companion animals.
abstract: In this study, 908 bacterial pathogens from defined infections of dogs and cats were tested for their susceptibility to the novel fluoroquinolone pradofloxacin, which was approved in 2011 for use in cats and dogs. Most of the bacteria tested (Staphylococcus aureus, Staphylococcus pseudintermedius, Escherichia coli, β-haemolytic streptococci, Pasteurella multocida and Bordetella bronchiseptica) exhibited low pradofloxacin MIC(90) values of ≤ 0.25 μg/ml. Solely Proteus spp. and Pseudomonas aeruginosa had higher MIC(90) values of ≥ 4 μg/ml. Only six (3.4%) of 177 S. pseudintermedius and 12 (5.3%) of 227 E. coli isolates showed pradofloxacin MICs of ≥ 2 μg/ml. Analysis of the quinolone resistance determining regions of the target genes identified double mutations in GyrA that resulted in amino acid exchanges S83L+D87N or S83L+D87Y and single or double mutations in ParC that resulted in amino acid exchanges S80I or S80I+E84G in all 12 E. coli isolates. The six S. pseudintermedius isolates exhibited amino acid exchanges S84L or E88K in GyrA and S80I in GrlA. Comparative analysis of the MICs of pradofloxacin and the MICs determined for enrofloxacin and its main metabolite ciprofloxacin, but also marbofloxacin, orbifloxacin, difloxacin and ibafloxacin was conducted for the target pathogens S. pseudintermedius, E. coli and P. multocida. This comparison confirmed that pradofloxacin MICs were significantly lower than those of the other tested fluoroquinolones.
authors.affiliation: Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), Neustadt-Mariensee, Germany.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Schink
authors.forename: Kristina
authors.initials: K
authors.lastname: Kadlec
authors.forename: Tomasz
authors.initials: T
authors.lastname: Hauschild
authors.forename: Geovana
authors.initials: G
authors.lastname: Brenner Michael
authors.forename: Julia C
authors.initials: JC
authors.lastname: Dörner
authors.forename: Carolin
authors.initials: C
authors.lastname: Ludwig
authors.forename: Christiane
authors.initials: C
authors.lastname: Werckenthin
authors.forename: Hans-Robert
authors.initials: HR
authors.lastname: Hehnen
authors.forename: Bernd
authors.initials: B
authors.lastname: Stephan
authors.forename: Stefan
authors.initials: S
authors.lastname: Schwarz
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002371:Cat Diseases / Q000382:microbiology*; D002415:Cats; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D004352:Drug Resistance, Microbial; D024841:Fluoroquinolones / Q000737:chemistry / Q000494:pharmacology*; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D057805:Pets / Q000382:microbiology*; D013210:Staphylococcus
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; C507250:pradofloxacin