Performances and Reliability of Bruker Microflex LT and VITEK MS MALDI-TOF Mass Spectrometry Systems for the Identification of Clinical Microorganisms

• Published in: BioMed research international 2015-01, Vol.2015 (2015), p.1-18
• Main Authors: Laleli, Yahya Rauf, Ciftci, Ugur, Yaman, Gorkem, Bilecen, Kivanc
• Format: Article
• Language: English
• Subjects: Automation; Bacteria; Bacteria - genetics; Bacteria - isolation & purification; Bacteria - pathogenicity; Biomedical research; Gram-positive bacteria; Health facilities; Humans; Identification and classification; Identification systems; Infection - diagnosis; Infection - genetics; Infection - microbiology; Laboratories; Libraries; Mass spectrometry; Methods; Microbiological Techniques; Microbiology; Microorganisms; Probability; R&D; Research & development; RNA, Ribosomal, 16S - genetics; RNA, Ribosomal, 16S - isolation & purification; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - instrumentation; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods
• ISSN: 2314-6133; 2314-6141
• DOI: 10.1155/2015/516410

In clinical microbiology laboratories, routine microbial identification is mostly performed using culture based methodologies requiring 24 to 72 hours from culturing to identification. Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) technology has been established as a cost effective, reliable, and faster alternative identification platform. In this study, we evaluated the reliability of the two available MALDI-TOF MS systems for their routine clinical level identification accuracy and efficiency in a clinical microbiology laboratory setting. A total of 1,341 routine phenotypically identified clinical bacterial and fungal isolates were selected and simultaneously analyzed using VITEK MS (bioMérieux, France) and Microflex LT (Bruker Diagnostics, Germany) MALDI-TOF MS systems. For any isolate that could not be identified with either of the systems and for any discordant result, 16S rDNA gene or ITS1/ITS2 sequencing was used. VITEK MS and Microflex LT correctly identified 1,303 (97.17%) and 1,298 (96.79%) isolates to the species level, respectively. In 114 (8.50%) isolates initial phenotypic identification was inaccurate. Both systems showed a similar identification efficiency and workflow robustness, and they were twice as more accurate compared to routine phenotypic identification in our sample pool. MALDITOF systems with their accuracy and robustness offer a good identification platform for routine clinical microbiology laboratories.