title: [Study on the molecular epidemiology of Stenotrophomonas maltophilia infection in patients on mechanical ventilation].
abstract: OBJECTIVE
  To investigate a potential outbreak of Stenotrophomonas maltophilia (pma) infection occurred in patients on mechanical ventilation in a respiratory ICU (RICU) and to track the infective origins by antibiotype and pulsed-field gel electrophoresis (PFGE) typing methods.
  
  
  METHODS
  (1) Thirteen pma strains were isolated from 9 patients on mechanical ventilation (9 strains), hand swabs of medical staffs in RICU (2 strains) and fiberscope used for intubations and aspiration (2 strains) from December, 2002 to February, 2003. (2) Sixteen strains gathered from different wards during the period of 1997 - 2000 were collected and used as control. (3) Antibiotic susceptibility data of all strains were collected. (4) Homology of the strains was analyzed by the methods of antibiotype and PFGE genotype.
  
  
  RESULTS
  Of the 9 pma isolated from patients on mechanical ventilation, eight had identical PFGE genotype. The isolates from two RICU staffs and two fiberscope displayed the same genotype with the eight patients above. Seven of the 9 isolates shared an identical antibiotype. The consistent rate of antibiotype with PFGE genotype was 85% (11/13). There were 11 PFGE genotypes and 9 antibiotypes in 16 strains of the control group, which indicated that they came from different clones.
  
  
  CONCLUSIONS
  Eight pma strains of patients in RICU came from the same clone. This result proved that clone transmission occurred in patients on mechanical ventilation. Contaminated fiberscope and hands of staffs may be the infective origin and the route of transmission.
authors.affiliation: Department of Respiratory Medicine, the First Affiliated Hospital, Chongqing University of Medical Sciences, Chongqing 400016, China.
authors.forename: Shu-liang
authors.initials: SL
authors.lastname: Guo
authors.forename: Li-xian
authors.initials: LX
authors.lastname: He
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Yun
authors.initials: Y
authors.lastname: Xia
authors.forename: Yong-ai
authors.initials: YA
authors.lastname: Luo
mesh_terms: D015373:Bacterial Typing Techniques; D003428:Cross Infection / Q000453:epidemiology* / Q000235:genetics; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D016905:Gram-Negative Bacterial Infections / Q000453:epidemiology* / Q000235:genetics; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D012121:Respiration, Artificial / Q000009:adverse effects*; D012124:Respiratory Care Units; D020615:Stenotrophomonas maltophilia / Q000145:classification / Q000302:isolation & purification*