RESUMO
Some extraintestinal pathogenic Escherichia coli isolates (ExPEC), obtained from humans and chickens avian pathogenic E. coli (APEC), share similar virulence genes. Thus, products of avian origin can be a source of human infection. Moreover, these APEC isolates are resistant to antimicrobials and can spread in the environment through the chicken feces. Although the development of multidrug-resistant (MDR) microorganisms in poultry is on the rise, healthcare entities have raised concerns since MDRs can horizontally transfer resistance genes to other microorganisms and complicate the management of human infections by MDR APEC. The results of our study showed that of 80 investigated spiced chicken meat samples, 55% were contaminated with E. coli, of which 34% (15/44) contaminate with APEC. No diarrheagenic E. coli (DEC) pathotypes were found. Twenty-six isolates were MDR E. coli. Among the APEC isolates, 87% (13/15) produced extended-spectrum beta-lactamase (ESBL). The emergence of MDR/ESBL-producing APEC with zoonotic potential for humans is extremely worrying. Therefore, further studies are required to identify the prevalence of MDR/ESBL-producing APEC in the entire chicken production chain from creation, slaughter, processing, and butchery.
Assuntos
Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Humanos , Escherichia coli , Galinhas , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Brasil/epidemiologia , Aves Domésticas , Hidrolases/genética , Doenças das Aves Domésticas/epidemiologia , Antibacterianos/farmacologia , Filogenia , CarneRESUMO
This study aimed to evaluate the antimicrobial activity of the dichloromethane fraction (DCMF) from the stem bark of Mimosa caesalpiniifolia and its effect on the activity of conventional antibiotics against Staphylococcus aureus strains overexpressing specific efflux pump genes. DCMF showed activity against S. aureus, Staphylococcus epidermidis and Candida albicans. Addition of DCMF at subinhibitory concentrations to the growth media enhanced the activity of norfloxacin, ciprofloxacin and ethidium bromide against S. aureus strains overexpressing norA suggesting the presence of efflux pump inhibitors in its composition. Similar results were verified for tetracycline against S. aureus overexpressing tetK, as well as, for ethidium bromide against S. aureus overexpressing qacC. These results indicate that M. caesalpiniifolia is a source of molecules able to modulate the fluoroquinolone- and tetracycline-resistance in S. aureus probably by inhibition of NorA, TetK and QacC respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: Drug resistance is a common problem in patients with infectious diseases. Dichloromethane fraction from the stem bark of Mimosa caesalpiniifolia showed antimicrobial activity against Gram-positive bacterium Staphylococcus aureus and against Candida albicans, but did not show activity against Gram-negative specie Escherichia coli. Moreover, this fraction was able to potentiate the action of norfloxacin, ciprofloxacin and tetracycline against S. aureus strains overexpressing different efflux pump genes. Thus, Mimosa caesalpiniifolia is a source of efflux pump inhibitors which could be used in combination with fluoroquinolones or tetracycline in the treatment of infectious diseases caused by S. aureus strains overexpressing efflux pump genes.