title: Coagulase-negative staphylococci in Southern Brazil: looking toward its high diversity.
abstract: BACKGROUND
  Coagulase-negative staphylococci (CoNS) are the most prevalent pathogens in nosocomial infections and may serve as a reservoir of mobile genetic elements such as the staphylococcal cassette chromosome mec (SCCmec) encoding methicillin resistance. Molecular characterization of SCCmec types combined with advanced molecular typing techniques may provide essential information for understanding the evolution and epidemiology of CoNS infections. We therefore aimed to investigate the SCCmec distribution, multidrug-resistance (MDR), and biofilm formation in CoNS blood culture isolates from a hospital in Southern Brazil.
  
  
  METHODS
  We analyzed 136 CoNS blood culture isolates obtained during 2002-2004 from patients admitted to a tertiary care hospital in Brazil. SCCmec types I to V were determined using multiplex PCR. The clonal relationship of Staphylococcus epidermidis was determined using pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Molecular epidemiological data were interpreted along with data on biofilm formation, presence of the icaD gene, and MDR.
  
  
  RESULTS
  The most prevalent species were S. epidermidis, Staphylococcus haemolyticus, and Staphylococcus hominis harboring mainly SCCmec types II, III, and V. Overall, the presence of multiple SCCmec was associated with non-MDR, except for S. epidermidis. S. epidermidis isolates showed a high prevalence of icaD, but had low phenotypic biofilm formation. PFGE and MLST revealed high genetic diversity in the S. epidermidis population.
  
  
  CONCLUSIONS
  Our results suggest a major shift in SCCmec types within a short period and reveal a different behavior of S. epidermidis with regard to the association between the presence of multiple SCCmec types and MDR profile.
authors.affiliation: Programa de Pós Graduação em Promoção da Saúde, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, Rio Grande do Sul, Brasil.
authors.forename: Caio Fernando de
authors.initials: CF
authors.lastname: Oliveira
authors.affiliation: Paediatric Research Group, Dept. of Clinical Medicine, Faculty of Health Sciences, UiT-The Artic University of Norway, Tromsø, Norway.|Department of Paediatrics, University Hospital of North Norway, Tromsø, Norway.
authors.forename: Jorunn Pauline
authors.initials: JP
authors.lastname: Cavanagh
authors.affiliation: Paediatric Research Group, Dept. of Clinical Medicine, Faculty of Health Sciences, UiT-The Artic University of Norway, Tromsø, Norway.|Department of Paediatrics, University Hospital of North Norway, Tromsø, Norway.
authors.forename: Elizabeth G Aarag
authors.initials: EG
authors.lastname: Fredheim
authors.affiliation: Departamento de Microbiologia e Parasitologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brasil.
authors.forename: Keli Cristine
authors.initials: KC
authors.lastname: Reiter
authors.affiliation: Laboratório de Biotecnologia e Genética, Universidade de Santa Cruz do Sul, Santa Cruz do Sul, Rio Grande do Sul, Brasil.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Rieger
authors.affiliation: Department of Paediatrics, University Hospital of North Norway, Tromsø, Norway.
authors.forename: Claus
authors.initials: C
authors.lastname: Klingenberg
authors.affiliation: Departamento de Microbiologia e Parasitologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brasil.
authors.forename: Pedro Alves
authors.initials: PA
authors.lastname: d'Azevedo
authors.affiliation: Research Group for Host-Microbe Interactions, Department of Medical Biology, Faculty of Health Sciences, UiT-The Artic University of Norway, Tromsø, Norway.
authors.forename: Johanna Ericson
authors.initials: JE
authors.lastname: Sollid
mesh_terms: D018441:Biofilms / Q000254:growth & development; D002876:Chromosomes, Bacterial / Q000235:genetics*; D003030:Coagulase / Q000096:biosynthesis; D004269:DNA, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D058885:Multilocus Sequence Typing; D013210:Staphylococcus / Q000145:classification* / Q000201:enzymology / Q000235:genetics
chemical_list: D003030:Coagulase; D004269:DNA, Bacterial