title: Molecular epidemiology of methicillin-resistant Staphylococcus aureus from bacteraemia in northern Italy.
abstract: BACKGROUND
  Vancomycin is frequently used in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia; reduced susceptibility to vancomycin is therefore disturbing.
  
  
  METHODS
  molecular epidemiological analysis of 81 MRSA bacteraemia isolates collected during 2002-10 in the province of Bolzano, northern Italy was performed. MICs of a range of antimicrobials were determined by agar microdilution, screening for hGISA was by Macro-Etest and Etest GRD and confirmed by PAP-AUC with vancomycin and teicoplanin. All isolates were characterised by toxin gene profiling, agr, spa, and SCCmec-typing; MLST and PFGE were carried out on representative strains.
  
  
  RESULTS
  The dominant clones identified were ST8-MRSA-IVc (55%) and ST228- and ST111-MRSA-I (25%); most of the latter two lineages (19/20; 95%) were GISA or PAP-AUC confirmed hGISA. One ST8-MRSA-IVc isolate harboured ccrA2B2 together with ccrA4B4. The remainder were diverse genotypically and belonged to MLST clonal complexes 1, 22, 45 and 398.
  
  
  CONCLUSIONS
  Diverse lineages of MRSA were identified as causing bacteraemia in a province in northern Italy. The association of a specific genotype with the hGISA and GISA phenotypes among representatives of the second most common lineage identified is of clinical concern.
authors.affiliation: Laboratorio Aziendale di Microbiologia e Virologia, Comprensorio Sanitario di Bolzano, Italy. richard.aschbacher@asbz.it
authors.forename: Richard
authors.initials: R
authors.lastname: Aschbacher
authors.forename: Bruno
authors.initials: B
authors.lastname: Pichon
authors.forename: Mandy
authors.initials: M
authors.lastname: Wootton
authors.forename: Leanne
authors.initials: L
authors.lastname: Davies
authors.forename: Raffaella
authors.initials: R
authors.lastname: Binazzi
authors.forename: Rachel
authors.initials: R
authors.lastname: Pike
authors.forename: Mark
authors.initials: M
authors.lastname: Ganner
authors.forename: Robert
authors.initials: R
authors.lastname: Hill
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Pagani
authors.forename: Iris
authors.initials: I
authors.lastname: Agreiter
authors.forename: Peter
authors.initials: P
authors.lastname: Mian
authors.forename: Clara
authors.initials: C
authors.lastname: Larcher
authors.forename: Angela
authors.initials: A
authors.lastname: Kearns
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000382:microbiology*; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000235:genetics; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017720:Molecular Epidemiology; D012189:Retrospective Studies; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D017334:Teicoplanin / Q000494:pharmacology; D014640:Vancomycin / Q000494:pharmacology; D020713:Vancomycin Resistance
chemical_list: D017334:Teicoplanin; D014640:Vancomycin