title: Virulence factors, antibiotic resistance phenotypes and O-serogroups of Escherichia coli strains isolated from community-acquired urinary tract infection patients in Mexico.
abstract: OBJECTIVE
  Uropathogenic Escherichia coli (UPEC) strains isolated from patients with community-acquired urinary tract infections (UTIs) were assessed to determine the prevalence of virulence genes, antibiotic resistance, and the O-serogroup of the strains.
  
  
  METHODS
  Consenting patients with community-acquired UTI were enrolled at Unidad Médica Familiar Number 64 (Instituto Mexicano del Seguro Social, Estado de Mexico, Mexico) and 321 urine samples were collected. Polymerase chain reaction (PCR) was used to assess 24 virulence genes and 14 O-serogroups. The Kirby-Bauer method was used to evaluate the antibiotic susceptibility of the isolated strains to 12 commonly used antibiotics.
  
  
  RESULTS
  A total of 194 strains were identified as E. coli using standard biochemical tests, followed by PCR amplification of 16S ribosomal RNA gene. Only 58.2% of the strains belonged to the assessed 14 O-serogroups. The serogroups O25, O15, O8, and O75 were present in 20.6%, 17%, 6.1%, and 4.6% of strains, respectively. The most frequently occurring virulence genes among UPEC strains included kpsMT (92.2% strains), usp (87.1%), irp2 (79.3%), iha (64.9%), fim (61.3%), set (36%), astA (33.5%), pap (24.7%), and papGII (21.1%). In addition, 97% of the strains were multi-drug resistant (coresistance to 3-11 antibiotics).
  
  
  CONCLUSIONS
  The isolated UPEC strains predominantly belonged to three serogroups (O25, O15, and O8), harboured numerous virulence genes, and are multiresistant to antibiotics. The findings of this study could be used to orient UTI treatment strategies and in epidemiological studies in Mexico.
authors.affiliation: FES Iztacala, Universidad Nacional Autónoma de México, Estado de Mexico, Mexico.
authors.forename: Gloria Luz
authors.initials: GL
authors.lastname: Paniagua-Contreras
authors.affiliation: FES Iztacala, Universidad Nacional Autónoma de México, Estado de Mexico, Mexico.
authors.forename: Eric
authors.initials: E
authors.lastname: Monroy-Pérez
authors.affiliation: Unidad Médica Familiar Number 64, Instituto Mexicano del Seguro Social, Juárez, Mexico.
authors.forename: José Raymundo
authors.initials: JR
authors.lastname: Rodríguez-Moctezuma
authors.affiliation: Unidad Médica Familiar Number 64, Instituto Mexicano del Seguro Social, Juárez, Mexico.
authors.forename: Pablo
authors.initials: P
authors.lastname: Domínguez-Trejo
authors.affiliation: FES Iztacala, Universidad Nacional Autónoma de México, Estado de Mexico, Mexico.
authors.forename: Felipe
authors.initials: F
authors.lastname: Vaca-Paniagua
authors.affiliation: FES Iztacala, Universidad Nacional Autónoma de México, Estado de Mexico, Mexico. Electronic address: vacasergio@gmail.com.
authors.forename: Sergio
authors.initials: S
authors.lastname: Vaca
mesh_terms: D000328:Adult; D000368:Aged; D016000:Cluster Analysis; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D052978:Disk Diffusion Antimicrobial Tests; D024881:Drug Resistance, Bacterial; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D019081:O Antigens / Q000032:analysis*; D010641:Phenotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D065288:Serogroup; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology*; D056689:Uropathogenic Escherichia coli / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification* / Q000472:pathogenicity; D037521:Virulence Factors / Q000032:analysis*; D055815:Young Adult
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D019081:O Antigens; D012336:RNA, Ribosomal, 16S; D037521:Virulence Factors
keywords: O-serogroup; UPEC; multidrug-resistance; virulence factors