title: Prevalence and risk factors associated with vancomycin-resistant Staphylococcus aureus precursor organism colonization among patients with chronic lower-extremity wounds in Southeastern Michigan.
abstract: BACKGROUND
  Of the 13 US vancomycin-resistant Staphylococcus aureus (VRSA) cases, 8 were identified in southeastern Michigan, primarily in patients with chronic lower-extremity wounds. VRSA infections develop when the vanA gene from vancomycin-resistant enterococcus (VRE) transfers to S. aureus. Inc18-like plasmids in VRE and pSK41-like plasmids in S. aureus appear to be important precursors to this transfer.
  
  
  OBJECTIVE
  Identify the prevalence of VRSA precursor organisms.
  
  
  METHODS
  Prospective cohort with embedded case-control study.
  
  
  METHODS
  Southeastern Michigan adults with chronic lower-extremity wounds.
  
  
  METHODS
  Adults presenting to 3 southeastern Michigan medical centers during the period February 15 through March 4, 2011, with chronic lower-extremity wounds had wound, nares, and perirectal swab specimens cultured for S. aureus and VRE, which were tested for pSK41-like and Inc18-like plasmids by polymerase chain reaction. We interviewed participants and reviewed clinical records. Risk factors for pSK41-positive S. aureus were assessed among all study participants (cohort analysis) and among only S. aureus-colonized participants (case-control analysis).
  
  
  RESULTS
  Of 179 participants with wound cultures, 26% were colonized with methicillin-susceptible S. aureus, 27% were colonized with methicillin-resistant S. aureus, and 4% were colonized with VRE, although only 17% consented to perirectal culture. Six participants (3%) had pSK41-positive S. aureus, and none had Inc18-positive VRE. Having chronic wounds for over 2 years was associated with pSK41-positive S. aureus colonization in both analyses.
  
  
  CONCLUSIONS
  Colonization with VRSA precursor organisms was rare. Having long-standing chronic wounds was a risk factor for pSK41-positive S. aureus colonization. Additional investigation into the prevalence of VRSA precursors among a larger cohort of patients is warranted.
authors.affiliation: Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. tosh.pritish@mayo.edu
authors.forename: Pritish K
authors.initials: PK
authors.lastname: Tosh
authors.forename: Simon
authors.initials: S
authors.lastname: Agolory
authors.forename: Bethany L
authors.initials: BL
authors.lastname: Strong
authors.forename: Kerrie
authors.initials: K
authors.lastname: Verlee
authors.forename: Jennie
authors.initials: J
authors.lastname: Finks
authors.forename: Kayoko
authors.initials: K
authors.lastname: Hayakawa
authors.forename: Teena
authors.initials: T
authors.lastname: Chopra
authors.forename: Keith S
authors.initials: KS
authors.lastname: Kaye
authors.forename: Nicholas
authors.initials: N
authors.lastname: Gilpin
authors.forename: Christopher F
authors.initials: CF
authors.lastname: Carpenter
authors.forename: Nadia Z
authors.initials: NZ
authors.lastname: Haque
authors.forename: Lois E
authors.initials: LE
authors.lastname: Lamarato
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Zervos
authors.forename: Valerie S
authors.initials: VS
authors.lastname: Albrecht
authors.forename: Sigrid K
authors.initials: SK
authors.lastname: McAllister
authors.forename: Brandi
authors.initials: B
authors.lastname: Limbago
authors.forename: Duncan R
authors.initials: DR
authors.lastname: Maccannell
authors.forename: Linda K
authors.initials: LK
authors.lastname: McDougal
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Kallen
authors.forename: Alice Y
authors.initials: AY
authors.lastname: Guh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007869:Leg Injuries / Q000150:complications / Q000382:microbiology; D008297:Male; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D020713:Vancomycin Resistance; D014946:Wound Infection / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology
references.citation: Antimicrob Agents Chemother. 2008 Feb;52(2):452-7
references.pmid: 18056272
references.citation: MMWR Morb Mortal Wkly Rep. 2002 Jul 5;51(26):565-7
references.pmid: 12139181
references.citation: J Chronic Dis. 1987;40(5):373-83
references.pmid: 3558716
references.citation: MMWR Morb Mortal Wkly Rep. 2004 Apr 23;53(15):322-3
references.pmid: 15103297
references.citation: Gerontologist. 1970 Spring;10(1):20-30
references.pmid: 5420677
references.citation: Clin Infect Dis. 2011 Dec;53(12):1215-22
references.pmid: 22080118
references.citation: Curr Microbiol. 2011 May;62(5):1363-7
references.pmid: 21234755
references.citation: Antimicrob Agents Chemother. 2004 Jan;48(1):275-80
references.pmid: 14693550
references.citation: J Clin Microbiol. 2003 Dec;41(12):5442-8
references.pmid: 14662923
references.citation: J Clin Microbiol. 2009 May;47(5):1344-51
references.pmid: 19321725
references.citation: Antimicrob Agents Chemother. 2013 Jan;57(1):212-9
references.pmid: 23089754
references.citation: Antimicrob Agents Chemother. 2007 Jan;51(1):231-8
references.pmid: 17074796
references.citation: Clin Infect Dis. 2001 May 15;32(10):1393-8
references.pmid: 11317238
references.citation: MMWR Morb Mortal Wkly Rep. 2002 Oct 11;51(40):902
references.pmid: 12418544
references.citation: Antimicrob Agents Chemother. 2010 Sep;54(9):3804-11
references.pmid: 20585117
references.citation: Emerg Infect Dis. 2009 Jun;15(6):943-5
references.pmid: 19523298
references.citation: Clin Infect Dis. 2008 Mar 1;46(5):668-74
references.pmid: 18257700
references.citation: Antimicrob Agents Chemother. 2010 Oct;54(10):4314-20
references.pmid: 20660665
references.citation: Infect Control Hosp Epidemiol. 2010 Jun;31(6):592-7
references.pmid: 20402589