title: [Methicillin-resistant Staphylococcus aureus colonization in a Colombian hospital intensive care unit: phenotypic and molecular characterization].
abstract: BACKGROUND
  Methicillin-resistant Staphylococcus aureus (MRSA) cause nosocomial and community infections. MRSA colonization in hospitals has been described as an important risk factor during hospitalization.
  
  
  OBJECTIVE
  The colonization characteristics of MRSA was described using the tools of molecular biology.
  
  
  METHODS
  Between February 2007 and February 2008, 705 patients entering a Colombian intensive care unit (ICU) were screened for MRSA by taking nasopharyngeal samples. For 683 of these patients, a weekly follow-up was provided after they left the ICU. The susceptibility of each S. aureus isolate was tested against 11 antibiotics using agar dilution methods. Sixty two percent (62.0%) of the MRSA isolates were characterized at genetic and molecular level with the detection of resistant genes, SCCmec typing using PCR and the genetic profile with pulsed field gel electrophoresis (PFGE).
  
  
  RESULTS
  Of the 705 patients screened at entry to the ICU, 182 (25.8%) were colonized by S. aureus, and of these, 51 (7.2%) were MRSA. Of the 683 patients with follow-up, 62 (9.1%) were infected by MRSA contracted in the hospital ICU. The prevalence of the Chilean clone was 76.5% at entry and 88.9% for follow-up patients. Of the 113 patients colonized with MRSA, nosocomial infection was present in 18 patients (16.0%). Three community-acquired MRSA isolates related to the USA300-0114 pandemic clone were identified. These were also positive for Panton-Valentine leucidin cytotoxin genes of S.aureus.
  
  
  CONCLUSIONS
  This is the first report in Colombia of patients colonized with CA-MRSA-ST8-SCCmec IVc isolates, and it is a probable source of dissemination of this bacteria in Colombian hospitals.
authors.affiliation: Vigilancia Epidemiológica, Hospital El Tunal, Bogotá, DC, Colombia. vigepi@hospitaleltunal.gov.co
authors.forename: Narda María
authors.initials: NM
authors.lastname: Olarte
authors.forename: Ismael Alberto
authors.initials: IA
authors.lastname: Valderrama
authors.forename: Karlo Roberto
authors.initials: KR
authors.lastname: Reyes
authors.forename: Martha Isabel
authors.initials: MI
authors.lastname: Garzón
authors.forename: Javier Antonio
authors.initials: JA
authors.lastname: Escobar
authors.forename: Betsy Esperanza
authors.initials: BE
authors.lastname: Castro
authors.forename: Natasha
authors.initials: N
authors.lastname: Vanegas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology; D003105:Colombia; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006779:Hospitals, Public; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008403:Mass Screening; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D008875:Middle Aged; D010641:Phenotype; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D055815:Young Adult