Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital

Talha Karabıyık; Ugur Demırpek; Süheyl Uçucu

doi:10.56766/ntms.1862930

Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital

Abstract

To compare bacterial identification using the VITEK 2 Compact (bioMérieux) and Bruker Microflex LT matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems in routine clinical microbiology. This retrospective cross-sectional study included consecutive clinical isolates recovered between February and April 2022 from a 1355-bed academic center. Identification was performed using VITEK 2 GN/GP cards and the Bruker MALDI Biotyper workflow using a Microflex LT instrument. Identifications were compared at species and genus levels; concordance was defined as identical taxon names. Agreement was summarized as percent agreement (Wilson 95% confidence intervals (CI)) and Cohen’s kappa (κ); discordance was interpreted as between-system disagreement because no molecular adjudication was performed. A total of 1394 isolates were analyzed. Most isolates were obtained from urine-related specimens (n=563, 40.4%) and blood cultures (n=446, 32.0%). Species-level concordance between systems was 93.1% (95% CI, 91.7–94.3%; κ=0.923 (95% CI, 0.908–0.937)), and genus-level concordance was 98.3% (95% CI, 97.5–98.8%; κ=0.979 (95% CI, 0.970–0.987)). Among the 96 discordant species identifications, 72 (75.0%) occurred within the same genus, indicating disagreements concentrated in closely related taxa. The most frequent discordant pairs involved the Klebsiella genus and coagulase-negative Staphylococcus species; the single most common pair was Klebsiella pneumoniae versus Klebsiella variicola (n=12). VITEK 2 and Bruker Microflex LT MALDI-TOF MS demonstrated very high agreement for routine bacterial identification, with most discrepancies occurring among closely related taxa. When species-level precision is clinically critical (e.g., outbreaks or invasive infections), confirmatory approaches such as 16S rRNA sequencing and up-to-date databases may be required.

Keywords

References

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Details

Primary Language

English

Subjects

Clinical Microbiology

Journal Section

Research Article

Authors

Talha Karabıyık ^*
0000-0002-1339-7348
Türkiye

Ugur Demırpek
0000-0001-5786-5265
Türkiye

Süheyl Uçucu
0000-0002-6320-2457
Türkiye

Publication Date

June 30, 2026

Submission Date

January 13, 2026

Acceptance Date

January 21, 2026

Published in Issue

Year 2026 Volume: 7 Number: 2

DOI

https://doi.org/10.56766/ntms.1862930

IZ

https://izlik.org/JA97XN74NB

Cite

RIS / Bibtex

APA

Karabıyık, T., Demırpek, U., & Uçucu, S. (2026). Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital. New Trends in Medicine Sciences, 7(2), 53-58. https://doi.org/10.56766/ntms.1862930

AMA

1.Karabıyık T, Demırpek U, Uçucu S. Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital. New Trend Med Sci. 2026;7(2):53-58. doi:10.56766/ntms.1862930

Chicago

Karabıyık, Talha, Ugur Demırpek, and Süheyl Uçucu. 2026. “Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital”. New Trends in Medicine Sciences 7 (2): 53-58. https://doi.org/10.56766/ntms.1862930.

EndNote

Karabıyık T, Demırpek U, Uçucu S (June 1, 2026) Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital. New Trends in Medicine Sciences 7 2 53–58.

IEEE

[1]T. Karabıyık, U. Demırpek, and S. Uçucu, “Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital”, New Trend Med Sci, vol. 7, no. 2, pp. 53–58, June 2026, doi: 10.56766/ntms.1862930.

ISNAD

Karabıyık, Talha - Demırpek, Ugur - Uçucu, Süheyl. “Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital”. New Trends in Medicine Sciences 7/2 (June 1, 2026): 53-58. https://doi.org/10.56766/ntms.1862930.

JAMA

1.Karabıyık T, Demırpek U, Uçucu S. Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital. New Trend Med Sci. 2026;7:53–58.

MLA

Karabıyık, Talha, et al. “Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital”. New Trends in Medicine Sciences, vol. 7, no. 2, June 2026, pp. 53-58, doi:10.56766/ntms.1862930.

Vancouver

1.Talha Karabıyık, Ugur Demırpek, Süheyl Uçucu. Comparison of VITEK 2 and Bruker Microflex LT MALDI-TOF MS for Routine Bacterial Identification in a Tertiary Hospital. New Trend Med Sci. 2026 Jun. 1;7(2):53-8. doi:10.56766/ntms.1862930