title: Rapid identification of positive blood cultures by matrix-assisted laser desorption ionization-time of flight mass spectrometry using prewarmed agar plates.
abstract: This study describes an inexpensive and straightforward method for identifying bacteria by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) directly from positive blood cultures using prewarmed agar plates. Different inoculation methods and incubation times were evaluated to determine the optimal conditions. The two methods using pelleted material from positive culture bottles performed best. In particular, the pellet streak method correctly identified 94% of the Gram negatives following 4 h of incubation and 98% of the Gram positives following 6 h of incubation.
authors.affiliation: Section of Infectious Diseases, Department of Pediatrics, Comer Children's Hospital, University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Bhatti
authors.affiliation: Section of Microbiology/Immunology, Department of Pathology, University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: S
authors.initials: S
authors.lastname: Boonlayangoor
authors.affiliation: Section of Microbiology/Immunology, Department of Pathology, University of Chicago Medicine, Chicago, Illinois, USA.
authors.forename: K G
authors.initials: KG
authors.lastname: Beavis
authors.affiliation: Section of Microbiology/Immunology, Department of Pathology, University of Chicago Medicine, Chicago, Illinois, USA vtesic@bsd.uchicago.edu.
authors.forename: V
authors.initials: V
authors.lastname: Tesic
mesh_terms: D016470:Bacteremia / Q000175:diagnosis*; D001419:Bacteria / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000379:methods*; D001769:Blood / Q000382:microbiology*; D006801:Humans; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013696:Temperature; D013997:Time Factors