title: Outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal intensive care unit linked to artificial nails.
abstract: BACKGROUND
  From April to June 2001, an outbreak of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae infections was investigated in our neonatal intensive care unit.
  
  
  METHODS
  Cultures of the gastrointestinal tracts of patients, the hands of healthcare workers (HCWs), and the environment were performed to detect potential reservoirs for ESBL-producing K. pneumoniae. Strains of K. pneumoniae were typed by pulsed-field gel electrophoresis using XbaI. A case-control study was performed to determine risk factors for acquisition of the outbreak clone (clone A); cases were infants infected or colonized with clone A and controls (3 per case) were infants with negative surveillance cultures.
  
  
  RESULTS
  During the study period, 19 case-infants, of whom 13 were detected by surveillance cultures, harbored clone A. The overall attack rate for the outbreak strain was 45%; 9 of 19 infants presented with invasive disease (n = 6) or developed invasive disease (n = 3) after colonization was detected. Clone A was found on the hands of 2 HCWs, 1 of whom wore artificial nails, and on the designated stethoscope of a case-infant. Multiple logistic regression analysis revealed that length of stay per day (odds ratio [OR], 1.05; 95% confidence interval [CI95], 1.02 to 1.09) and exposure to the HCW wearing artificial fingernails (OR, 7.87; CI95, 1.75 to 35.36) were associated with infection or colonization with clone A.
  
  
  CONCLUSIONS
  Short, well-groomed, natural nails should be mandatory for HCWs with direct patient contact
authors.affiliation: Department of Pediatrics, Columbia University, New York-Presbyterian Hospital, New York, New York 10032, USA.
authors.forename: Archana
authors.initials: A
authors.lastname: Gupta
authors.forename: Phyllis
authors.initials: P
authors.lastname: Della-Latta
authors.forename: Betsy
authors.initials: B
authors.lastname: Todd
authors.forename: Pablo
authors.initials: P
authors.lastname: San Gabriel
authors.forename: Janet
authors.initials: J
authors.lastname: Haas
authors.forename: Fann
authors.initials: F
authors.lastname: Wu
authors.forename: David
authors.initials: D
authors.lastname: Rubenstein
authors.forename: Lisa
authors.initials: L
authors.lastname: Saiman
mesh_terms: D016022:Case-Control Studies; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission*; D004196:Disease Outbreaks / Q000517:prevention & control; D004197:Disease Reservoirs; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006225:Hand / Q000382:microbiology; D006801:Humans; D007231:Infant, Newborn; D017053:Infection Control; D017757:Infectious Disease Transmission, Professional-to-Patient; D007363:Intensive Care Units, Neonatal; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000517:prevention & control; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000302:isolation & purification*; D016015:Logistic Models; D008297:Male; D009262:Nails / Q000382:microbiology*; D009519:New York City / Q000453:epidemiology; D009741:Nursing Staff, Hospital; D012307:Risk Factors; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases