Use of MALDI-TOF MS (Bruker Daltonics) for identification of Mycobacterium species isolated directly from liquid medium / Utilización de MALDI-TOF MS (Bruker Daltonics) para la identificación de micobacterias aisladas directamente en medio líquido

Objectives: The aim of this study was to describe the evaluation of the use of MALDI-TOF MS for the identification of non-tuberculous mycobacteria (NTM) and Mycobacterium tuberculosis directly from liquid MGIT cultures from January 2017 to December 2017. Material/methods: A total of 155 isolates (mainly respiratory) were analyzed by MALDI-TOF MS (Bruker Daltonics) directly from MGIT liquid medium with a previous extraction procedure. Results: MALDI-TOF MS generated acceptable scores for 152 isolates (98.06%). Fifty isolates were identified as M. tuberculosis complex and the remaining 105 as NTM (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum and M. xenopi). Conclusions: These results indicate that MALDI-TOF MS can be useful to identify mycobacteria directly from MGIT cultures and is an accurate, rapid and cost-effective system to be used as a routine method.(AU)

Introducción: Evaluamos la espectrometría de masas (MALDI-TOF MS [Bruker Daltonics]) para la identificación de micobacterias no tuberculosas (MNT) y Mycobacterium tuberculosis a partir de cultivos líquidos (MGIT) desde enero del 2017 a diciembre del 2017. Métodos: Se analizaron mediante MALDI-TOF MS 155 cultivos MGIT positivos, principalmente de origen respiratorio. Previamente a la realización de MALDI-TOF se realizó un procedimiento de extracción directamente del MGIT. Resultados: Mediante MALDI-TOF MS se identificó correctamente a partir del MGIT el 98,06% (n=152) de los aislados. Cincuenta aislados se identificaron como M. tuberculosis complex y los 105 restantes como MNT (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum y M. xenopi). Conclusiones: Estos resultados indican que MALDI-TOF es una técnica precisa, rápida y coste-efectiva para identificar micobacterias directamente a partir de medios de cultivo líquidos en la rutina diaria.(AU)

Use of MALDI-TOF MS (Bruker Daltonics) for identification of Mycobacterium species isolated directly from liquid medium.

OBJECTIVES: The aim of this study was to describe the evaluation of the use of MALDI-TOF MS for the identification of non-tuberculous mycobacteria (NTM) and Mycobacterium tuberculosis directly from liquid MGIT cultures from January 2017 to December 2017. MATERIAL/METHODS: A total of 155 isolates (mainly respiratory) were analyzed by MALDI-TOF MS (Bruker Daltonics) directly from MGIT liquid medium with a previous extraction procedure. RESULTS: MALDI-TOF MS generated acceptable scores for 152 isolates (98.06%). Fifty isolates were identified as M. tuberculosis complex and the remaining 105 as NTM (M. abscessus subsp. abscessus, M. avium, M. celatum, M chelonae, M. chimaera, M. fortuitum, M. gordonae, M. intracellulare, M. kansasii, M. lentiflavum, M. mageritense, M. mucogenicum and M. xenopi). CONCLUSIONS: These results indicate that MALDI-TOF MS can be useful to identify mycobacteria directly from MGIT cultures and is an accurate, rapid and cost-effective system to be used as a routine method.