Title

Multi-centre evaluation of mass spectrometric identification of anaerobic bacteria using the VITEK (R) MS system

Publication Date

2014

Journal Title

Clin Microbiol Infect

Abstract

Accurate and timely identification of anaerobic bacteria is critical to successful treatment. Classic phenotypic methods for identification require long turnaround times and can exhibit poor species level identification. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an identification method that can provide rapid identification of anaerobes. We present a multi-centre study assessing the clinical performance of the VITEK (R) MS in the identification of anaerobic bacteria. Five different test sites analysed a collection of 651 unique anaerobic isolates comprising 11 different genera. Multiple species were included for several of the genera. Briefly, anaerobic isolates were applied directly to a well of a target plate. Matrix solution (-cyano-4-hydroxycinnamic acid) was added and allowed to dry. Mass spectra results were generated with the VITEK (R) MS, and the comparative spectral analysis and organism identification were determined using the VITEK (R) MS database 2.0. Results were confirmed by 16S rRNA gene sequencing. Of the 651 isolates analysed, 91.2% (594/651) exhibited the correct species identification. An additional eight isolates were correctly identified to genus level, raising the rate of identification to 92.5%. Genus-level identification consisted of Actinomyces, Bacteroides and Prevotella species. Fusobacterium nucleatum, Actinomyces neuii and Bacteroides uniformis were notable for an increased percentage of no-identification results compared with the other anaerobes tested. VITEK (R) MS identification of clinically relevant anaerobes is highly accurate and represents a dramatic improvement over other phenotypic methods in accuracy and turnaround time.

Volume Number

20

Issue Number

4

Pages

335-339

Document Type

Article

Status

Faculty; Northwell Researcher

Facility

School of Medicine; Northwell Health

Primary Department

Pathology and Laboratory Medicine

Additional Departments

Molecular Medicine

PMID

23927597

DOI

10.1111/1469-0691.12317