title: Rapid and high-throughput genotyping of Staphylococcus epidermidis isolates by automated multilocus variable-number of tandem repeats: a tool for real-time epidemiology.
abstract: Fast and reliable genotyping methods allowing real-time epidemiology would be instrumental to discriminate Staphylococcus epidermidis isolates, in order to evaluate potential cross-infections or to follow genome content of infecting strains of this important opportunistic pathogen. We describe an automated multilocus variable-number tandem repeat-based assay (MLVA) for the rapid genotyping of S. epidermidis. Multiplex PCR amplifications using 6 primer pairs targeting gene-regions containing variable numbers of tandem repeats and the mecA gene are resolved by micro-capillary electrophoresis and automatically assessed by cluster analysis. This genotyping technique was evaluated for discriminatory power and reproducibility on 2 sequenced strains, on a collection of 21 strains previously characterized using genotyping reference methods and finally on 65 clinical isolates identified in two different institutions. All steps of this new procedure were developed to ensure rapid turn-around time and moderate costs. Our results suggest that this rapid approach is a valuable epidemiological tool to genotype S. epidermidis isolates in real-time. The rapid analysis of a limited number of evolutionary markers showed a power of discrimination similar to that of pulse-field gel electrophoresis (PFGE) or multilocus sequence type (MLST). This type of rapid and high-throughput methodology opens the possibility to rapidly assess long-term nosocomial transmission or to characterize infecting strains in the general procedure of routine laboratories, in real-time.
authors.affiliation: University of Geneva Hospitals, CH-1211 Geneva 14, Switzerland. patrice.francois@genomic.ch
authors.forename: Patrice
authors.initials: P
authors.lastname: Francois
authors.forename: Alena
authors.initials: A
authors.lastname: Hochmann
authors.forename: Antoine
authors.initials: A
authors.lastname: Huyghe
authors.forename: Eve-Julie
authors.initials: EJ
authors.lastname: Bonetti
authors.forename: Gesuele
authors.initials: G
authors.lastname: Renzi
authors.forename: Stephan
authors.initials: S
authors.lastname: Harbarth
authors.forename: Claus
authors.initials: C
authors.lastname: Klingenberg
authors.forename: Didier
authors.initials: D
authors.lastname: Pittet
authors.forename: Jacques
authors.initials: J
authors.lastname: Schrenzel
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques / Q000379:methods*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000235:genetics; D019075:Electrophoresis, Capillary; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D018598:Minisatellite Repeats; D017720:Molecular Epidemiology / Q000379:methods*; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013212:Staphylococcus epidermidis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C487495:MecA protein, Staphylococcus epidermidis