title: Antimicrobial resistance and prevalence of resistance genes in intestinal Bacteroidales strains.
abstract: OBJECTIVE
  This study examined the antimicrobial resistance profile and the prevalence of resistance genes in Bacteroides spp. and Parabacteroides distasonis strains isolated from children's intestinal microbiota.
  
  
  METHODS
  The susceptibility of these bacteria to 10 antimicrobials was determined using an agar dilution method. β-lactamase activity was assessed by hydrolysis of the chromogenic cephalosporin of 114 Bacteriodales strains isolated from the fecal samples of 39 children, and the presence of resistance genes was tested using a PCR assay.
  
  
  RESULTS
  All strains were susceptible to imipenem and metronidazole. The following resistance rates were observed: amoxicillin (93%), amoxicillin/clavulanic acid (47.3%), ampicillin (96.4%), cephalexin (99%), cefoxitin (23%), penicillin (99%), clindamycin (34.2%) and tetracycline (53.5%). P-lactamase production was verified in 92% of the evaluated strains. The presence of the cfiA, cepA, ermF, tetQ and nim genes was observed in 62.3%, 76.3%, 27%, 79.8% and 7.8% of the strains, respectively.
  
  
  CONCLUSIONS
  Our results indicate an increase in the resistance to several antibiotics in intestinal Bacteroides spp. and Parabacteroides distasonis and demonstrate that these microorganisms harbor antimicrobial resistance genes that may be transferred to other susceptible intestinal strains.
authors.affiliation: Anaerobe Laboratory, Department of Microbiology, Institute of Biomedical Sciences, São Paulo University, SP, Brazil. vivinkn@usp.br
authors.forename: Viviane
authors.initials: V
authors.lastname: Nakano
authors.forename: Amanda do
authors.initials: Ad
authors.lastname: Nascimento e Silva
authors.forename: Victor Rafael Castillo
authors.initials: VR
authors.lastname: Merino
authors.forename: Hannah M
authors.initials: HM
authors.lastname: Wexler
authors.forename: Mario Julio
authors.initials: MJ
authors.lastname: Avila-Campos
mesh_terms: D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001439:Bacteroides / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D002648:Child; D024881:Drug Resistance, Bacterial / Q000187:drug effects / Q000235:genetics*; D005798:Genes, Bacterial / Q000187:drug effects / Q000235:genetics; D006801:Humans; D015378:Imipenem / Q000494:pharmacology; D007422:Intestines / Q000382:microbiology*; D008795:Metronidazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole; D015378:Imipenem