Peptide nucleic acid fluorescence in situ hybridization for rapid detection of Klebsiella pneumoniae from positive blood cultures.
This study evaluated a novel peptide nucleic acid (PNA) probe targeting a region of the 23S rRNA gene of Klebsiella pneumoniae by fluorescence in situ hybridization (FISH). Analytical performance was determined using 39 reference strains and other well-characterized strains of Klebsiella spp. and Enterobacter aerogenes. The probe was found to be specific for the K. pneumoniae complex (K. pneumoniae including Klebsiella ozaenae and Klebsiella variicola). The diagnostic accuracy was evaluated with 264 blood cultures containing Gram-negative rods. Using conventional identification as the reference, performance specifications were as follows: sensitivity 98.8 %, specificity 99.5 %, positive predictive value 98.8 % and negative predictive value 99.5 %. Discrepancies were resolved by PNA FISH retest and phenotypic tests. In conclusion, the K. pneumoniae probe provided an accurate diagnosis within 3 h and may supplement other methods for direct identification of Gram-negative bacteria.
Søgaard
Mette
M
Department of Clinical Epidemiology, Aalborg Hospital, Aarhus University Hospital, Aarhus, Denmark.|Department of Clinical Microbiology, Aalborg Hospital, Aarhus University Hospital, Postbox 365, 9100 Aalborg, Denmark.
Hansen
Dennis S
DS
Department of Clinical Microbiology, Hillerød Sygehus, Denmark.|The International Escherichia and Klebsiella Reference Center (WHO), Statens Serum Institut, Copenhagen, Denmark.
Fiandaca
Mark J
MJ
AdvanDx Inc., Woburn, MA, USA.
Stender
Henrik
H
AdvanDx Inc., Woburn, MA, USA.
Schønheyder
Henrik C
HC
Department of Clinical Microbiology, Aalborg Hospital, Aarhus University Hospital, Postbox 365, 9100 Aalborg, Denmark.
D016470:Bacteremia / Q000382:microbiology; D015373:Bacterial Typing Techniques; D001431:Bacteriological Techniques; D001769:Blood / Q000382:microbiology*; D003470:Culture Media; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D015341:Nucleic Acid Probes / Q000235:genetics*; D020135:Peptide Nucleic Acids / Q000235:genetics*; D013997:Time Factors
D003470:Culture Media; D015341:Nucleic Acid Probes; D020135:Peptide Nucleic Acids