Comparison of two methods skipping cell lysis and protein extraction for identification of bacteria from blood cultures by matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry

Objective. Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) is widely used for fast identification of bacteria from blood cultures (BC). We compared the performance of two procedures, one including a pre-enrichment step in brain heart infusion and the other...

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Detalles Bibliográficos
Autores: Torres, I, Gimenez, E, Huntley, D, Martinez, M, Colomina, J, Navarro, D
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:INCLIVA
Repositorio:r-INCLIVA. Repositorio Institucional de Producción Científica de INCLIVA
OAI Identifier:oai:incliva.fundanetsuite.com:p3913
Acceso en línea:https://incliva.portalinvestigacion.com/publicaciones/3913
Access Level:acceso abierto
Palabra clave:MALDI-TOF M
blood culture
bacterial identification
Descripción
Sumario:Objective. Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) is widely used for fast identification of bacteria from blood cultures (BC). We compared the performance of two procedures, one including a pre-enrichment step in brain heart infusion and the other a direct method using vacutainer separator gel tubes (DI), for identification of bacteria from blood cultures by MAL-DI-TOF MS. Material and methods. We first prepared a training set of 20 simulated bacteremia specimens, including 10 Gram-negative and 10 Gram-positive species. A total of 145 non-consecutive BCs flagged as positive (68 Gram-negative rods, and 77 Gram-positive cocci) were prospectively analyzed (validation set). Results. A total of 82% and 49% of isolates were correctly identified to the species level by the respective methods. Conclusion. The pre-enrichment method outperformed the DI method for identification of virtually all bacterial species included in the panels.