Comparison of the Vitek MS and Bruker Microflex LT MALDI-TOF MS platforms for routine identification of commonly isolated bacteria and yeast in the clinical microbiology laboratory

Eszter Deak; Carmen L Charlton; April M Bobenchik; Shelley A Miller; Simon Pollett; Ian H McHardy; Max T Wu; Omai B Garner

doi:10.1016/j.diagmicrobio.2014.09.018

Comparison of the Vitek MS and Bruker Microflex LT MALDI-TOF MS platforms for routine identification of commonly isolated bacteria and yeast in the clinical microbiology laboratory

Diagn Microbiol Infect Dis. 2015 Jan;81(1):27-33. doi: 10.1016/j.diagmicrobio.2014.09.018. Epub 2014 Sep 28.

Authors

Eszter Deak¹, Carmen L Charlton², April M Bobenchik¹, Shelley A Miller¹, Simon Pollett³, Ian H McHardy¹, Max T Wu¹, Omai B Garner⁴

Affiliations

¹ Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA.
² Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada.
³ Sydney Institute of Emerging Infections and Biosecurity, University of Sydney, Sydney, New South Wales, Australia.
⁴ Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, USA. Electronic address: ogarner@mednet.ucla.edu.

PMID: 25446889
DOI: 10.1016/j.diagmicrobio.2014.09.018

Abstract

This study compared the diagnostic performance of Bruker's Microflex LT and bioMérieux's Vitek MS matrix-assisted laser desorption ionization-time of flight mass spectrometry systems. A total of 477 isolates were tested on both instruments. Discrepant results were resolved by sequencing. Overall, there was no statistically significant difference between the proportion of isolates correctly identified, miscalled or not called by each instrument. Although both systems were good at identifying yeast (66/69 to species level), the confidence level was high only to genus level for 30% of the isolates on the Bruker. Both systems performed with high accuracy when evaluated solely on Food and Drug Administration-approved organisms for each database. A user-based assessment of the 2 instruments revealed an overall preference for the Vitek MS instrument.

Keywords: Bacteriology; Clinical microbiology; MALDI-TOF; Mycology; Rapid identification.

Publication types

Comparative Study
Research Support, Non-U.S. Gov't

MeSH terms

Gram-Negative Bacteria / classification
Gram-Negative Bacteria / genetics
Gram-Negative Bacteria / isolation & purification
Gram-Positive Bacteria / classification
Gram-Positive Bacteria / genetics
Gram-Positive Bacteria / isolation & purification
Humans
Medical Laboratory Personnel
Molecular Typing / instrumentation*
Molecular Typing / methods
Mycological Typing Techniques / instrumentation*
Mycological Typing Techniques / methods
RNA, Ribosomal, 16S
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / instrumentation*
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / methods
United States
United States Food and Drug Administration
Yeasts / classification*
Yeasts / isolation & purification

Substances

RNA, Ribosomal, 16S