title: Rapid Identification of Microorganisms from Positive Blood Culture by MALDI-TOF MS After Short-Term Incubation on Solid Medium.
abstract: Matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is a useful tool for rapid identification of microorganisms. Unfortunately, its direct application to positive blood culture is still lacking standardized procedures. In this study, we evaluated an easy- and rapid-to-perform protocol for MALDI-TOF MS direct identification of microorganisms from positive blood culture after a short-term incubation on solid medium. This protocol was used to evaluate direct identification of microorganisms from 162 positive monomicrobial blood cultures; at different incubation times (3, 5, 24 h), MALDI-TOF MS assay was performed from the growing microorganism patina. Overall, MALDI-TOF MS concordance with conventional methods at species level was 60.5, 80.2, and 93.8% at 3, 5, and 24 h, respectively. Considering only bacteria, the identification performances at species level were 64.1, 85.0, and 94.1% at 3, 5, and 24 h, respectively. This protocol applied to a commercially available MS typing system may represent, a fast and powerful diagnostic tool for pathogen direct identification and for a promptly and pathogen-driven antimicrobial therapy in selected cases.
authors.affiliation: Microbiology and Virology Unit, Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino, Corso Bramante 88, 10126, Turin, Italy. antonio.curtoni@gmail.com.
authors.forename: Antonio
authors.identifier: http://orcid.org/0000-0001-8101-4196
authors.initials: A
authors.lastname: Curtoni
authors.affiliation: Microbiology and Virology Unit, Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino, Corso Bramante 88, 10126, Turin, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Cipriani
authors.affiliation: Bacteriology and Mycology Laboratory, Department of Public Health and Pediatrics, University of Turin, Turin, Italy.
authors.forename: Elisa Simona
authors.initials: ES
authors.lastname: Marra
authors.affiliation: Microbiology and Virology Unit, Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino, Corso Bramante 88, 10126, Turin, Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Barbui
authors.affiliation: Microbiology and Virology Unit, Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino, Corso Bramante 88, 10126, Turin, Italy.
authors.forename: Rossana
authors.initials: R
authors.lastname: Cavallo
authors.affiliation: Microbiology and Virology Unit, Azienda Ospedaliero Universitaria Città della Salute e della Scienza di Torino, Corso Bramante 88, 10126, Turin, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Costa
mesh_terms: D016470:Bacteremia / Q000097:blood / Q000175:diagnosis / Q000382:microbiology*; D001419:Bacteria / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D001681:Biological Assay; D001769:Blood / Q000382:microbiology*; D000071997:Blood Culture; D003470:Culture Media / Q000378:metabolism; D006801:Humans; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003470:Culture Media