title: A cluster of Mycobacterium wolinskyi surgical site infections at an academic medical center.
abstract: OBJECTIVE
  To study a cluster of Mycobacterium wolinskyi surgical site infections (SSIs).
  
  
  METHODS
  Observational and case-control study.
  
  
  METHODS
  Academic hospital.
  
  
  METHODS
  Subjects who developed SSIs with M. wolinskyi following cardiothoracic surgery.
  
  
  METHODS
  Electronic surveillance was performed for case finding as well as electronic medical record review of infected cases. Surgical procedures were observed. Medical chart review was conducted to identify risk factors. A case-control study was performed to identify risk factors for infection; Fisher exact or Kruskal-Wallis tests were used for comparisons of proportions and medians, respectively. Patient isolates were studied using pulsed-field gel electrophoresis (PFGE). Environmental microbiologic sampling was performed in operating rooms, including high-volume water sampling.
  
  
  RESULTS
  Six definite cases of M. wolinskyi SSI following cardiothoracic surgery were identified during the outbreak period (October 1, 2008-September 30, 2011). Having cardiac surgery in operating room A was significantly associated with infection (odds ratio, 40; P = .0027). Observational investigation revealed a cold-air blaster exclusive to operating room A as well a microbially contaminated, self-contained water source used in heart-lung machines. The isolates were indistinguishable or closely related by PFGE. No environmental samples were positive for M. wolinskyi.
  
  
  CONCLUSIONS
  No single point source was established, but 2 potential sources, including a cold-air blaster and a microbially contaminated, self-contained water system used in heart-lung machines for cardiothoracic operations, were identified. Both of these potential sources were removed, and subsequent active surveillance did not reveal any further cases of M. wolinskyi SSI.
authors.affiliation: Division of Infectious Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Avish
authors.initials: A
authors.lastname: Nagpal
authors.forename: Jean E
authors.initials: JE
authors.lastname: Wentink
authors.forename: Elie F
authors.initials: EF
authors.lastname: Berbari
authors.forename: Kimberly C
authors.initials: KC
authors.lastname: Aronhalt
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Wright
authors.forename: Dale A
authors.initials: DA
authors.lastname: Krageschmidt
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Wengenack
authors.forename: Rodney L
authors.initials: RL
authors.lastname: Thompson
authors.forename: Pritish K
authors.initials: PK
authors.lastname: Tosh
mesh_terms: D000046:Academic Medical Centers; D006348:Cardiac Surgical Procedures; D016022:Case-Control Studies; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D017053:Infection Control; D008297:Male; D008875:Middle Aged; D008910:Minnesota; D009161:Mycobacterium / Q000302:isolation & purification*; D009164:Mycobacterium Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control