title: Orthopaedic-implant infections by Escherichia coli: molecular and phenotypic analysis of the causative strains.
abstract: OBJECTIVE
  Little is known about Escherichia coli Orthopaedic Implant Infections (OII) pathogenesis. Thus, we compared 30 clinical strains isolated in this context with 30 clinical strains of faecal origin, in order to identify phenotypic and genetic features related to E. coli OII.
  
  
  METHODS
  Phylogenetic analysis and detection of 19 virulence genes were performed by PCR. Ability to form biofilm was studied using the crystal violet reference method and the innovative BioFilm Ring Test(®).
  
  
  RESULTS
  Most of the OII isolates (56.7%) belonged to the virulence-associated phylogenetic group B2, but did not present a specific set of virulence factors. S fimbriae was the only adhesin significantly associated with OII isolates. Isolates varied greatly in their ability to form biofilm but OII isolates did not produce significantly more biofilm in vitro than isolates of faecal origin, whatever the method used.
  
  
  CONCLUSIONS
  Neither a specific pathogenic signature nor an increased ability to form biofilm in vitro was detected in E. coli strains isolated from OII. Nevertheless, genetic properties of these isolates could provide a clue to their origin. Hence, we found that virulence factors of uropathogenic strains and urological disorders were frequently detected among our OII cohort.
authors: Service de Bactériologie-Hygiène, CHU de Nantes, 9 quai Moncousu 44093 Nantes Cedex 1, France.
authors: Lise
authors: L
authors: Crémet
authors: Stéphane
authors: S
authors: Corvec
authors: Pascale
authors: P
authors: Bémer
authors: Laurent
authors: L
authors: Bret
authors: Cécile
authors: C
authors: Lebrun
authors: Béatrice
authors: B
authors: Lesimple
authors: Anne-Françoise
authors: AF
authors: Miegeville
authors: Alain
authors: A
authors: Reynaud
authors: Didier
authors: D
authors: Lepelletier
authors: Nathalie
authors: N
authors: Caroff
mesh_terms: D018830:Adhesins, Escherichia coli / Q000032:analysis; D000368:Aged; D000369:Aged, 80 and over; D018441:Biofilms / Q000254:growth & development; D004926:Escherichia coli / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity* / Q000502:physiology; D004927:Escherichia coli Infections / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D005260:Female; D036781:Fimbriae Proteins / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D016459:Prosthesis-Related Infections / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D018830:Adhesins, Escherichia coli; D037521:Virulence Factors; D036781:Fimbriae Proteins