title: Rapid urine preparation prior to identification of uropathogens by MALDI-TOF MS.
abstract: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-ToF MS) has been introduced in clinical routine microbiology laboratories. For the rapid diagnosis of urinary tract infections, culture-independent methods prior MALDI-mediated identification have been described. Here, we describe a comparison of three of these methods based on their performance of bacterial identification and their potential as a routine tool for microbiology labs : (i) differential centrifugation, (ii) urine filtration and (iii) a 5-h bacterial cultivation on solid culture media. For 19 urine samples, all methods were directly compared and correct bacterial species identification by MALDI was used as performance indicator. A higher percentage of correct MALDI identification was obtained after filtration (78.9 %) and the growth-based method (84.2 %) as compared to differential centrifugation (68.4 %). Additional testing of 76 mono-microbial specimens (bacteriuria > 10(5) CFU/mL) confirmed the good performance of short growth with a 90.8 % correct MALDI score, with a potentially better fit to the routine workflow of microbiology labs.
authors.affiliation: Innovation/Technology Research Department, bioMérieux S.A., Chemin de l'Orme, 69280, Marcy L'Etoile, France, laurent.veron@biomerieux.com.
authors.forename: L
authors.initials: L
authors.lastname: Veron
authors.forename: S
authors.initials: S
authors.lastname: Mailler
authors.forename: V
authors.initials: V
authors.lastname: Girard
authors.forename: B H
authors.initials: BH
authors.lastname: Muller
authors.forename: G
authors.initials: G
authors.lastname: L'Hostis
authors.forename: C
authors.initials: C
authors.lastname: Ducruix
authors.forename: A
authors.initials: A
authors.lastname: Lesenne
authors.forename: A
authors.initials: A
authors.lastname: Richez
authors.forename: H
authors.initials: H
authors.lastname: Rostaing
authors.forename: V
authors.initials: V
authors.lastname: Lanet
authors.forename: S
authors.initials: S
authors.lastname: Ghirardi
authors.forename: A
authors.initials: A
authors.lastname: van Belkum
authors.forename: F
authors.initials: F
authors.lastname: Mallard
mesh_terms: D057205:Automation, Laboratory; D015373:Bacterial Typing Techniques; D001437:Bacteriuria / Q000175:diagnosis*; D006801:Humans; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D016482:Urinalysis / Q000379:methods*; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000382:microbiology