title: Performance of Vitek MS in identifying nontuberculous mycobacteria from MGIT liquid medium and Lowenstein-Jensen solid medium.
abstract: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry is a fast and inexpensive method for bacterial identification. The aim of this study was to analyze the performance of Vitek MS in identifying 160 nontuberculous mycobacterial isolates of 24 species from Lowenstein-Jensen solid medium and BACTEC MGIT 960 liquid medium using a bead-based method. The system correctly identified 76.9% of the isolates (123 of 160) cultivated on solid medium and 76.9% (123 of 160) of positive liquid cultures. None of the isolates included in the study was misidentified. Although the overall performance of Vitek MS with the SARAMIS 4.12 database was comparable in identifying mycobacterial species grown on solid medium and in liquid medium, the identification rate varied notably between the various species analyzed, which currently limits the utility for identification in routine diagnostics for some species.
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany. Electronic address: jan.kehrmann@uk-essen.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Kehrmann
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Ann-Kathrin
authors.initials: AK
authors.lastname: Schoerding
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Roshni
authors.initials: R
authors.lastname: Murali
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Wessel
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Hedda Luise
authors.initials: HL
authors.lastname: Koehling
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Mosel
authors.affiliation: Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Buer
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D003470:Culture Media / Q000737:chemistry; D006801:Humans; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis*; D009170:Nontuberculous Mycobacteria / Q000737:chemistry / Q000145:classification* / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D003470:Culture Media
keywords: Identification; MALDI-TOF MS; Mycobacteria; NTM; Vitek MS