Direct Bacterial Identification in Positive Blood Cultures by Use of Two Commercial Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Systems
Open Access
- 1 June 2013
- journal article
- research article
- Published by American Society for Microbiology in Journal of Clinical Microbiology
- Vol. 51 (6), 1733-1739
- https://doi.org/10.1128/jcm.03259-12
Abstract
Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) for the identification of bacteria and fungi was recently introduced in microbiology laboratories. This technology could greatly improve the clinical management of patients and guidance for chemotherapy. In this study, we used a commercial MALDI Sepsityper extraction method to evaluate the performance of two commercial MALDI-TOF MS systems, the Vitek MS IVD (bioMérieux) and the Microflex LT Biotyper (Bruker Daltonics) for direct bacterial identification in positive blood cultures. In 181 monomicrobial cultures, both systems generated genus to species level identifications for >90% of the specimens (Biotyper, 177/181 [97.8%]; Vitek MS IVD, 167/181 [92.3%]). Overall, the Biotyper system generated significantly more accurate identifications than the Vitek MS IVD system (P= 0.016; 177 versus 167 out of 181 specimens). The Biotyper system identified the minority species among polymicrobial blood cultures. We also compared the performance of an in-house extraction method with that of the Sepsityper on both MALDI-TOF MS systems. The in-house method generated more correct identifications at the genus level than the Sepsityper (96.7% versus 93.5%) on the Biotyper system, whereas the two methods exhibited the same performance level (88.0% versus 88.0%) on the Vitek MS IVD system. Our study confirmed the practical advantages of MALDI-TOF MS, and our in-house extraction method reduced the reagent cost to $1 per specimen, with a shorter turnaround time of 3 h, which is highly cost-effective for a diagnostic microbiology service.Keywords
This publication has 29 references indexed in Scilit:
- Prospective Evaluation of a Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry System in a Hospital Clinical Microbiology Laboratory for Identification of Bacteria and Yeasts: a Bench-by-Bench Study for Assessing the Impact on Time to Identification and Cost-EffectivenessJournal of Clinical Microbiology, 2012
- Comparison of the Microflex LT and Vitek MS Systems for Routine Identification of Bacteria by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass SpectrometryJournal of Clinical Microbiology, 2012
- Direct Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry Improves Appropriateness of Antibiotic Treatment of BacteremiaPLOS ONE, 2012
- Direct MALDI-TOF Mass Spectrometry Assay of Blood Culture Broths for Rapid Identification of Candida Species Causing Bloodstream Infections: an Observational Study in Two Large Microbiology LaboratoriesJournal of Clinical Microbiology, 2012
- Identification of Bacteria in Blood Culture Broths Using Matrix-Assisted Laser Desorption-Ionization Sepsityper™ and Time of Flight Mass SpectrometryPLOS ONE, 2011
- Improved Identification of Yeast Species Directly from Positive Blood Culture Media by Combining Sepsityper Specimen Processing and Microflex Analysis with the Matrix-Assisted Laser Desorption Ionization Biotyper SystemJournal of Clinical Microbiology, 2011
- Automated Identification of Medically Important Bacteria by 16S rRNA Gene Sequencing Using a Novel Comprehensive Database, 16SpathDBJournal of Clinical Microbiology, 2011
- Comparison of Bruker Biotyper Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometer to BD Phoenix Automated Microbiology System for Identification of Gram-Negative BacilliJournal of Clinical Microbiology, 2011
- Rapid Identification of Bacteria in Positive Blood Culture Broths by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass SpectrometryJournal of Clinical Microbiology, 2010
- Evaluation of Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry in Comparison to 16S rRNA Gene Sequencing for Species Identification of Nonfermenting BacteriaJournal of Clinical Microbiology, 2008