title: Outbreak of colonizations by extended-spectrum β-lactamase-producing Escherichia coli sequence type 131 in a neonatal intensive care unit, Italy.
abstract: BACKGROUND
  Extended spectrum β-lactamases (ESBLs) often associated with resistance to aminoglycosides and fluoroquinolones have recently emerged in community-associated Escherichia coli. The worldwide clonal dissemination of E. coli sequence type (ST)131 is playing a prominent role.We describe an outbreak of colonizations by ESBL-producing E. coli (ESBL-E. coli) in the neonatal intensive care unit (NICU) of the University Hospital, Palermo, Italy.
  
  
  METHODS
  An epidemiological investigation was conducted with the support of molecular typing. All children admitted to the NICU and colonized by ESBL-E. coli between January and June 2012, were included in the study. Cases were defined as infants colonized by E. coli resistant to third generation cephalosporins and fluoroquinolones. A case-control study was also performed to identify possible risk factors.
  
  
  RESULTS
  During the outbreak period, 15 infants were found to be colonized by ESBL-E. coli. The epidemic strain demonstrated continuous transmission throughout the outbreak period. Case-control study identified a lower birth weight as the only risk factor for colonization. The strain belonged to the sequence-type 131 community-associated clone. Transmission control interventions, including contact precautions and cohorting, restriction of the new admissions, sanitization of surfaces and equipment and targeted training sessions of the NICU staff, were successful in interrupting the outbreak.
  
  
  CONCLUSIONS
  Although invasive infections did not develop in any of the 15 colonized neonates, our report highlights the need to strictly monitor the spill in the NICU setting of multidrug resistant community-associated organisms. Our findings confirm also the role of active surveillance in detecting the silent spread of ESBL-producing Gram negatives in a critical healthcare setting and trigging the implementation of infection control measures. As β-lactam and fluoroquinolone resistant E. coli strains are increasingly spreading in the community, this event could become a more serious challenge.
authors.affiliation: Department of Sciences for Health Promotion and Mother-Child Care "G, D'Alessandro", University of Palermo, Via del Vespro 133, I-90127, Palermo, Italy. caterina.mammina@unipa.it.
authors.forename: Mario
authors.initials: M
authors.lastname: Giuffrè
authors.forename: Domenico
authors.initials: D
authors.lastname: Cipolla
authors.forename: Celestino
authors.initials: C
authors.lastname: Bonura
authors.forename: Daniela Maria
authors.initials: DM
authors.lastname: Geraci
authors.forename: Aurora
authors.initials: A
authors.lastname: Aleo
authors.forename: Stefania
authors.initials: S
authors.lastname: Di Noto
authors.forename: Federica
authors.initials: F
authors.lastname: Nociforo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Corsello
authors.forename: Caterina
authors.initials: C
authors.lastname: Mammina