title: Identification of microorganisms grown on chromogenic media by MALDI-TOF MS.
abstract: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and chromogenic media are widely used in clinical microbiology laboratories to facilitate the rapid selection and identification of pathogens. The aim of this study was to evaluate whether usage of chromogenic media limits the diagnostic performance of MALDI-TOF MS for microbial identification. A total of 386 microorganisms collected and analyzed at five laboratories were included. Isolates were cultured on relevant chromogenic media and non-selective agar plates in parallel and identified using the Bruker MALDI-TOF MS. Among the tested isolates, no misidentification was recorded and there was no medium-related difference in the identification level. However, score values were overall slightly but significantly lower for isolates grown on chromogenic media. In conclusion, the use of chromogenic culture media tested here had no relevant impact on MALDI-TOF MS performance for diagnostic purposes.
authors.affiliation: Division of Clinical Microbiology, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden. Electronic address: Petra.Luthje@ki.se.
authors.forename: Petra
authors.initials: P
authors.lastname: Lüthje
authors.affiliation: MVZ Dr. Eberhard & Partner Dortmund (ÜBAG), Dortmund, Germany.
authors.forename: Arthur B
authors.initials: AB
authors.lastname: Pranada
authors.affiliation: The Ottawa Hospital, Ottawa, Canada.
authors.forename: Duncan
authors.initials: D
authors.lastname: Carruthers-Lay
authors.affiliation: The Ottawa Hospital, Ottawa, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Desjardins
authors.affiliation: Centre Hospitalier Régional Universitaire de Lille, Lille, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Gaillot
authors.affiliation: Queen Mary University London, London, UK; Division of Infection, Barts Health NHS Trust, London, UK.
authors.forename: David
authors.initials: D
authors.lastname: Wareham
authors.affiliation: Division of Infection, Barts Health NHS Trust, London, UK.
authors.forename: Holly
authors.initials: H
authors.lastname: Ciesielczuk
authors.affiliation: Division of Clinical Microbiology, Karolinska University Hospital Huddinge, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Volkan
authors.initials: V
authors.lastname: Özenci
mesh_terms: D001419:Bacteria / Q000254:growth & development* / Q000302:isolation & purification* / Q000472:pathogenicity; D001424:Bacterial Infections / Q000175:diagnosis; D001431:Bacteriological Techniques / Q000379:methods*; D002863:Chromogenic Compounds / Q000737:chemistry*; D003470:Culture Media / Q000737:chemistry*; D005658:Fungi / Q000254:growth & development* / Q000302:isolation & purification* / Q000472:pathogenicity; D007753:Laboratories; D057230:Limit of Detection; D055624:Methicillin-Resistant Staphylococcus aureus / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity; D009181:Mycoses / Q000175:diagnosis; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*; D065507:Vancomycin-Resistant Enterococci / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity
chemical_list: D002863:Chromogenic Compounds; D003470:Culture Media
keywords: Bacterial identification; Chromogenic media; Culture conditions; MALDI-TOF MS