title: Methicillin-resistant Staphylococcus aureus in Rio de Janeiro hospitals: dissemination of the USA400/ST1 and USA800/ST5 SCCmec type IV and USA100/ST5 SCCmec type II lineages in a public institution and polyclonal presence in a private one.
abstract: BACKGROUND
  Methicillin-resistant Staphylococcus aureus (MRSA) infections have changed since certain non-multiresistant MRSA lineages have emerged in hospitals. In this study, 99 MRSA isolates, 77 from a public and 22 from a private hospital, were characterized.
  
  
  METHODS
  Isolates were tested for antimicrobial susceptibility, whereas staphylococcal chromosomal cassette mec (SCCmec) typing and Panton-Valentine leukocidin genes were assessed by polymerase chain reaction. Pulsed-field gel electrophoresis and multilocus sequence typing analyses were carried out to determine the MRSA lineages.
  
  
  RESULTS
  High rates of resistance were found to erythromycin (96%), ciprofloxacin (93%), and clindamycin (90%). The SCCmec types found were as follows: type II (14.2%), III (62.6%), and IV (23.2%). Approximately 85% of type III isolates was related to the Brazilian epidemic clone in both hospitals. For type IV isolates, 94.4% were related to both USA400/ sequence type (ST) 1 and USA800/ST5 lineages in the public hospital, whereas the USA400/ST1, USA800/ST5, USA1100/ST30, and EMRSA (Epidemic MRSA)-15/ST22 lineages were detected in the private hospital. Among the SCCmec II isolates, approximately 85% were related to the USA100/ST5 lineage. Three MRSA isolates were positive to Panton-Valentine leukocidin genes.
  
  
  CONCLUSIONS
  The study showed that there was an emergence of USA400/ST1, USA800/ST5 SCCmec IV, and USA100/ST5 SCCmec II MRSA lineages in both hospitals. There was a dissemination of them in the public hospital and a polyclonal presence of the MRSA isolates in the private hospital. The spread of these lineages can be facilitated by the characteristics of the health institution.
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Brazil.
authors.forename: Roberta Mello Ferreira
authors.initials: RM
authors.lastname: Caboclo
authors.forename: Fernanda Sampaio
authors.initials: FS
authors.lastname: Cavalcante
authors.forename: Natalia Lopes Pontes
authors.initials: NL
authors.lastname: Iorio
authors.forename: Ricardo Pinto
authors.initials: RP
authors.lastname: Schuenck
authors.forename: André Nogueira
authors.initials: AN
authors.lastname: Olendzki
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Felix
authors.forename: Raiane Cardoso
authors.initials: RC
authors.lastname: Chamon
authors.forename: Kátia Regina Netto
authors.initials: KR
authors.lastname: dos Santos
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001427:Bacterial Toxins / Q000235:genetics; D001938:Brazil / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics; D005098:Exotoxins / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D006761:Hospitals; D006801:Humans; D007956:Leukocidins / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; D037521:Virulence Factors