Optimization of the score cutoff value for routine identification of Staphylococcus species by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry

Huan Wen Han, Hsien-Chang Chang, Ay Huei Hunag, Tsung Chain Chang

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Staphylococcus species are important pathogens. We evaluated 2 score cutoffs (2.0 and 1.7) and the replicate number (a single or a duplicate test) on the identification of staphylococci using the Bruker matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). A collection of 440 clinical isolates (11 species) and 144 reference strains (36 species) was evaluated. For clinical isolates using a cutoff of 2.0 and duplicate tests, the rates of species, genus, and unreliable identifications were 93.4%, 5.7%, and 0.9% respectively, while the respective values were 99.3%, 0.2%, and 0.5% when the cutoff was 1.7. The species identification rates were significantly higher ( P< 0.01) when a cutoff of 1.7 or a duplicate test was used. Similar results were obtained for reference strains. In conclusion, a cutoff of 1.7 and duplicate tests are recommended for identification of staphylococci using MALDI-TOF MS.

Original languageEnglish
Pages (from-to)349-354
Number of pages6
JournalDiagnostic Microbiology and Infectious Disease
Volume83
Issue number4
DOIs
Publication statusPublished - 2015 Dec 1

Fingerprint

Staphylococcus
Mass Spectrometry
Lasers

All Science Journal Classification (ASJC) codes

  • Microbiology (medical)
  • Infectious Diseases

Cite this

@article{f3b975c0134940b8b92bf2115ab1333e,
title = "Optimization of the score cutoff value for routine identification of Staphylococcus species by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry",
abstract = "Staphylococcus species are important pathogens. We evaluated 2 score cutoffs (2.0 and 1.7) and the replicate number (a single or a duplicate test) on the identification of staphylococci using the Bruker matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). A collection of 440 clinical isolates (11 species) and 144 reference strains (36 species) was evaluated. For clinical isolates using a cutoff of 2.0 and duplicate tests, the rates of species, genus, and unreliable identifications were 93.4{\%}, 5.7{\%}, and 0.9{\%} respectively, while the respective values were 99.3{\%}, 0.2{\%}, and 0.5{\%} when the cutoff was 1.7. The species identification rates were significantly higher ( P< 0.01) when a cutoff of 1.7 or a duplicate test was used. Similar results were obtained for reference strains. In conclusion, a cutoff of 1.7 and duplicate tests are recommended for identification of staphylococci using MALDI-TOF MS.",
author = "Han, {Huan Wen} and Hsien-Chang Chang and Hunag, {Ay Huei} and Chang, {Tsung Chain}",
year = "2015",
month = "12",
day = "1",
doi = "10.1016/j.diagmicrobio.2015.08.003",
language = "English",
volume = "83",
pages = "349--354",
journal = "Diagnostic Microbiology and Infectious Disease",
issn = "0732-8893",
publisher = "Elsevier Inc.",
number = "4",

}

TY - JOUR

T1 - Optimization of the score cutoff value for routine identification of Staphylococcus species by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry

AU - Han, Huan Wen

AU - Chang, Hsien-Chang

AU - Hunag, Ay Huei

AU - Chang, Tsung Chain

PY - 2015/12/1

Y1 - 2015/12/1

N2 - Staphylococcus species are important pathogens. We evaluated 2 score cutoffs (2.0 and 1.7) and the replicate number (a single or a duplicate test) on the identification of staphylococci using the Bruker matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). A collection of 440 clinical isolates (11 species) and 144 reference strains (36 species) was evaluated. For clinical isolates using a cutoff of 2.0 and duplicate tests, the rates of species, genus, and unreliable identifications were 93.4%, 5.7%, and 0.9% respectively, while the respective values were 99.3%, 0.2%, and 0.5% when the cutoff was 1.7. The species identification rates were significantly higher ( P< 0.01) when a cutoff of 1.7 or a duplicate test was used. Similar results were obtained for reference strains. In conclusion, a cutoff of 1.7 and duplicate tests are recommended for identification of staphylococci using MALDI-TOF MS.

AB - Staphylococcus species are important pathogens. We evaluated 2 score cutoffs (2.0 and 1.7) and the replicate number (a single or a duplicate test) on the identification of staphylococci using the Bruker matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). A collection of 440 clinical isolates (11 species) and 144 reference strains (36 species) was evaluated. For clinical isolates using a cutoff of 2.0 and duplicate tests, the rates of species, genus, and unreliable identifications were 93.4%, 5.7%, and 0.9% respectively, while the respective values were 99.3%, 0.2%, and 0.5% when the cutoff was 1.7. The species identification rates were significantly higher ( P< 0.01) when a cutoff of 1.7 or a duplicate test was used. Similar results were obtained for reference strains. In conclusion, a cutoff of 1.7 and duplicate tests are recommended for identification of staphylococci using MALDI-TOF MS.

UR - http://www.scopus.com/inward/record.url?scp=84947040446&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84947040446&partnerID=8YFLogxK

U2 - 10.1016/j.diagmicrobio.2015.08.003

DO - 10.1016/j.diagmicrobio.2015.08.003

M3 - Article

VL - 83

SP - 349

EP - 354

JO - Diagnostic Microbiology and Infectious Disease

JF - Diagnostic Microbiology and Infectious Disease

SN - 0732-8893

IS - 4

ER -