Escherichia spp

From Dog
Pyometra as a result of endometrial infection with E. coli[1]

Escherichia spp are a ubiquitous Gram-negative, anaerobic bacteria found on dog skin and mucus membranes.

Escherichia coli is the most pathogenic species which infect dogs, and is highly resistant to many antimicrobial drugs[2].

This bacteria is a common cause of diarrhoea associated with gastroenteritis, granulomatous colitis in French Bulldogs[3], cystitis[4], endometritis[5], pyometra[6], peritonitis[7] and pneumonia and is one of the main species of bacteria living in the lower intestine. It is a zoonotic bacteria, capable of spreading between most mammalian species.

When located in the large intestine, E. coli bacteria assists with waste processing, vitamin K-production, and food absorption. As with all Gram-negative organisms, E. coli are unable to sporulate (unlike Clostridium spp, which sporulate, and causes tetanus - 'lockjaw'). Thus, treatments which kill all active bacteria, such as pasteurisation or simple boiling, are effective for their eradication.

Pathogenic symptoms induced by these diarrhoeagenic E. coli can be due to production of toxins or other virulence traits. Extended-spectrum β-lactamase (ESBL)-producing E. coli have also been recorded.

Several assays are available for detection of diarrhoeagenic E. coli, including biochemical reactions, serotyping and phenotypic assays based on virulence characteristics. However, molecular detection by PCR has become a commonly-used method to detect and identify these bacteria because the method gives rapid and reliable results in addition to its high sensitivity and specificity.

Certain strains of E. coli behave as pathogens in dogs causing gastro-intestinal and extra-intestinal diseases.

Treatment usually involves broad-spectrum antimicrobials including amoxicillin/clavulanate and clindamycin.

Resistance to fluoroquinolones such as enrofloxacin[8] and cephalosporins[9] has been reported.


  1. Vet Surgery Central
  2. So JH et al (2012) Dissemination of multidrug-resistant Escherichia coli in Korean veterinary hospitals. Diagn Microbiol Infect Dis 73(2):195-199
  3. Manchester AC et al (2013) Association between granulomatous colitis in French Bulldogs and invasive Escherichia coli and response to fluoroquinolone antimicrobials. J Vet Intern Med 27(1):56-61
  4. Nam EH et al (2013) Characterization and Zoonotic Potential of Uropathogenic Escherichia coli Isolated from Dogs. J Microbiol Biotechnol 23(3):422-429
  5. Krekeler N et al (2012) Effect of simulated stages of the canine oestrous cycle on Escherichia coli binding to canine endometrium. Reprod Domest Anim 47(6):331-334
  6. Holst BS et al (2013) Leucocyte phagocytosis during the luteal phase in bitches. Vet Immunol Immunopathol Feb 13
  7. Cioffi KM et al (2012) Retrospective evaluation of vacuum-assisted peritoneal drainage for the treatment of septic peritonitis in dogs and cats: 8 cases (2003-2010). J Vet Emerg Crit Care (San Antonio) doi: 10.1111
  8. Platell JL et al (2012) Prominence of an O75 clonal group (clonal complex 14) among non-ST131 fluoroquinolone-resistant Escherichia coli causing extraintestinal infections in humans and dogs in Australia. Antimicrob Agents Chemother 56(7):3898-3904
  9. Sato T et al (2013) Phylogenetic association of fluoroquinolone- and cephalosporin-resistance of D-O1-ST648 Escherichia coli carrying blaCMY-2 from fecal samples of dogs in Japan. J Med Microbiol Feb 21