Virulence genotypes and phylogenetic background of fluoroquinolone-resistant and susceptible Escherichia coli urine isolates from dogs with urinary tract infection.
The origins and virulence potential of fluoroquinolone-resistant (FQ-R) Escherichia coli from dogs with urinary tract infection (UTI) are undefined. Therefore, fluoroquinolone-resistant (n=38) or susceptible (n=62) E. coli urine isolates from dogs with UTI were characterized for phylogenetic group (A, B1, B2, D) and 61 virulence-associated genes by multiplex PCR, then were compared according to these characteristics. Compared with fluoroquinolone-susceptible (FQ-S) isolates, the fluoroquinolone-resistant isolates exhibited significantly lower prevalences for most virulence genes studied (albeit higher prevalences for several, including iutA: aerobactin receptor), significantly fewer virulence genes per isolate, and shifts away from virulence-associated group B2. Nonetheless, 26% of fluoroquinolone-resistant isolates qualified as extraintestinal pathogenic E. coli (ExPEC), suggesting possible human virulence potential. The findings call into question whether the fluoroquinolone-resistant E. coli encountered in dogs arise through conversion of fluoroquinolone-susceptible canine resident strains to resistance, or instead are imported from an external source. They also identify dogs as a possible reservoir of drug-resistant ExPEC for transmission to other pets and humans.
Johnson
James R
JR
Veterans Affairs Medical Center, Minneapolis, MN, USA. johns007@umn.edu
Kuskowski
Michael A
MA
Owens
Krista
K
Clabots
Connie
C
Singer
Randall S
RS
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004283:Dog Diseases / Q000382:microbiology* / Q000652:urine; D004285:Dogs; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000382:microbiology / Q000662:veterinary*; D024841:Fluoroquinolones / Q000494:pharmacology*; D005838:Genotype; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D025341:Principal Component Analysis; D014552:Urinary Tract Infections / Q000382:microbiology / Q000652:urine / Q000662:veterinary*; D014774:Virulence
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D024841:Fluoroquinolones