Raman spectroscopic analysis of the clonal and horizontal spread of CTX-M-15-producing Klebsiella pneumoniae in a neonatal intensive care unit.
Nosocomial outbreaks of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae are an increasing concern in neonatal intensive care units (NICUs). We describe an outbreak of ESBL-producing K. pneumoniae that lasted 5 months and affected 23 neonates in our NICU. Proton pump inhibitor and extended-spectrum cephalosporin exposure were significantly associated with the risk of ESBL-producing K. pneumoniae colonisation and/or infection. Thirty isolates recovered from clinical, screening and environmental samples in the NICU were studied by means of Raman spectroscopy, pulsed-field gel electrophoresis and repetitive extragenic palindromic polymerase chain reaction (rep-PCR). The Raman clustering was in good agreement with the results of the other two molecular methods. Fourteen isolates belonged to the Raman clone 1 and 16 to the Raman clone 3. Molecular analysis showed that all the strains expressed SHV-1 chromosomal resistance, plasmid-encoded TEM-1 and CTX-M-15 β-lactamases. Incompatibility groups of plasmid content identified by PCR-based replicon typing indicated that resistance dissemination was due to the clonal spread of K. pneumoniae and horizontal CTX-M-15 gene transfer between the two clones.
APHP, Laboratoire de Microbiologie, Hôpital Robert Debré, 48, Bld. Serurier, 75935 Paris, France.
K
K
Guyot
V
V
Biran
C
C
Doit
D
D
Moissenet
T
T
Guillard
L
L
Brasme
C
C
Courroux
K
K
Maquelin
W
W
van Leeuwen
H
H
Vuthien
Y
Y
Aujard
C
C
De Champs
E
E
Bingen
D019980:Amoxicillin-Potassium Clavulanate Combination / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D002439:Cefotaxime / Q000494:pharmacology; D004196:Disease Outbreaks; D018562:Disease Transmission, Infectious; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D050456:Fomites / Q000382:microbiology; D005602:France / Q000453:epidemiology; D005798:Genes, Bacterial; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics / Q000472:pathogenicity*; D008297:Male; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D012307:Risk Factors; D013059:Spectrum Analysis, Raman; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
D019980:Amoxicillin-Potassium Clavulanate Combination; C473109:beta-lactamase CTX-M-15; C054882:beta-lactamase PIT-2; D001618:beta-Lactamases; C034413:beta-lactamase TEM-1; D002439:Cefotaxime