title: MALDI-TOF MS meets WGS in a VRE outbreak investigation.
abstract: The use of MALDI-TOF MS (matrix-assisted laser desorption/ ionization-time of flight mass spectrometry) and WGS (whole genome sequencing) has been described for identification and strain relatedness determination. We describe the complementary use of MALDI-TOF MS and WGS in a VRE (vancomycin-resistant enterococci) outbreak investigation, and discuss some of the challenges with defining strain similarity across these two platforms. Although both assays indicated multiple clusters involved in the outbreak of vancomycin resistant Enterococcus faecium isolates from positive blood cultures of four haematology-oncology patients, the small cohort and discrepancies between findings indicate the limitations of MALDI-TOF MS and the cautious interpretation of MALDI-TOF MS dendrograms during outbreaks. For definitive determination of the evolutionary distance between isolates, WGS can be used.
authors.affiliation: Pathology Department, Mater Health Services, South Brisbane, QLD, Australia. sanmarie.schlebusch@mater.org.au.|School of Medicine, The University of Queensland, St Lucia, Australia. sanmarie.schlebusch@mater.org.au.
authors.forename: S
authors.initials: S
authors.lastname: Schlebusch
authors.affiliation: Pathology Department, Mater Health Services, South Brisbane, QLD, Australia.
authors.forename: G R
authors.initials: GR
authors.lastname: Price
authors.affiliation: Pathology Department, Mater Health Services, South Brisbane, QLD, Australia.
authors.forename: R L
authors.initials: RL
authors.lastname: Gallagher
authors.affiliation: Pathology Department, Mater Health Services, South Brisbane, QLD, Australia.
authors.forename: V
authors.initials: V
authors.lastname: Horton-Szar
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia.
authors.forename: L D H
authors.initials: LD
authors.lastname: Elbourne
authors.affiliation: School of Medicine, The University of Queensland, St Lucia, Australia.|Department of Medicine, Mater Health Services, South Brisbane, QLD, Australia.|QIMR Berghofer, Brisbane, Australia.
authors.forename: P
authors.initials: P
authors.lastname: Griffin
authors.affiliation: Pathology Department, Mater Health Services, South Brisbane, QLD, Australia.|School of Medicine, The University of Queensland, St Lucia, Australia.|MRI-UQ, Mater Health Services, South Brisbane, QLD, Australia.
authors.forename: D J
authors.initials: DJ
authors.lastname: Venter
authors.affiliation: Molecular Medicine Research Group, School of Medicine, Western Sydney University, Sydney, NSW, Australia.|Antibiotic Resistance and Mobile Elements Group, Ingham Institute for Applied Medical Research, Sydney, NSW, Australia.
authors.forename: S O
authors.initials: SO
authors.lastname: Jensen
authors.affiliation: Department of Microbiology and Infectious Diseases, Royal Prince Alfred Hospital, Sydney, Australia.
authors.forename: S J
authors.initials: SJ
authors.lastname: Van Hal
mesh_terms: D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology; D015373:Bacterial Typing Techniques / Q000379:methods; D004196:Disease Outbreaks; D016984:Enterococcus faecium / Q000737:chemistry / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology* / Q000382:microbiology; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006801:Humans; D017720:Molecular Epidemiology / Q000379:methods; D017422:Sequence Analysis, DNA / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D065507:Vancomycin-Resistant Enterococci / Q000737:chemistry / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification