Resumo

Pyometra (uterine inflammation with accumulation of pus in the uteri) is regarded as one of the most common illnesses in bitches. The ethiology and pathogenesis are complex with both hormonal and bacterial elements. The bacteria most frequently isolated from the uteri horn in pyometra is Escherichia coli. Twenty-eight cases of pyometra diagnosed at a private clinic in Ituverava city, São Paulo State, were studied from March to August 2012. Immediately after removal of the uteri, samples were taken from each uteri horn, and a sterile cotton swab was collected from the mouth (saliva) and the rectum (feces) of each bitch. All specimens were inoculated onto MacConkey agar and the isolated colonies were submitted to biochemical tests to confirm as E. coli isolates. Using 6 bitches with E. coli growth in all the sites (25 isolates from pus, 26 isolates from saliva and 19 isolates from feces), 70 E. coli isolates were examined for the presence of uropathogenic virulence genes by PCR, susceptibility to 12 antimicrobial drugs and their DNA-profiles were compared by REP-PCR, ERIC-PCR and BOX-PCR. Virulence gene frequencies detected in those strains were: fimH was found in 67 (95.7%) strains; iss was observed in 19 (27.1%) strains; hlyA was detected in 18 (25.7%) strains; iucD was observed in 13 (18.5%) strains and usp in 12 (17.1%) strains. None of the samples analyzed were positive for papGII.Only 2 isolates(2.8%)did not present positivity for any of the virulence genes analyzed. Predominant resistance was to cephalothin, ampicillin and nalidixis acid among the strains from all sites examined. Multidrug resistance was found among strains above to 40%. Using the genotypic methods some strains from uteri pus and saliva of the same bitch proved to have identical DNA-profiles what is a reason for concern due to the close relationship between household pets and humans.