title: Direct Identification of Urinary Tract Pathogens from Urine Samples, Combining Urine Screening Methods and Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry.
abstract: Early diagnosis of urinary tract infections (UTIs) is essential to avoid inadequate or unnecessary empirical antibiotic therapy. Microbiological confirmation takes 24 to 48 h. The use of screening methods, such as cytometry and automated microscopic analysis of urine sediment, allows the rapid prediction of negative samples. In addition, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a widely established technique in clinical microbiology laboratories used to identify microorganisms. We evaluated the ability of MALDI-TOF MS to identify microorganisms from direct urine samples and the predictive value of automated analyzers for the identification of microorganisms in urine by MALDI-TOF MS. A total of 451 urine samples from patients with suspected UTIs were first analyzed using the Sysmex UF-1000iflow cytometer, an automatic sediment analyzer with microscopy (SediMax), culture, and then processed by MALDI-TOF MS with a simple triple-centrifuged procedure to obtain a pellet that was washed and centrifuged and finally applied directly to the MALDI-TOF MS plate. The organisms in 336 samples were correctly identified, mainly those with Gram-negative bacteria (86.10%). No microorganisms were misidentified, and noCandidaspp. were correctly identified. Regarding the data from autoanalyzers, the best bacteriuria cutoffs were 1,000 and 200 U/μl for UF-1000iand SediMax, respectively. It was concluded that the combination of a urine screening method and MALDI-TOF MS provided a reliable identification from urine samples, especially in those containing Gram-negative bacteria.
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain vausina.germanstrias@gencat.cat.
authors.forename: Melania
authors.initials: M
authors.lastname: Íñigo
authors.affiliation: Microbiology Service, Fundació Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol, Hospital Universitari Germans Trias i Pujol, Autonomous University of Barcelona, Badalona, Spain.
authors.forename: Andreu
authors.initials: A
authors.lastname: Coello
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Fernández-Rivas
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain.
authors.forename: Belén
authors.initials: B
authors.lastname: Rivaya
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain Microbiology Service, Fundació Institut d'Investigació en Ciències de la Salut Germans Trias i Pujol, Hospital Universitari Germans Trias i Pujol, Autonomous University of Barcelona, Badalona, Spain.
authors.forename: Jessica
authors.initials: J
authors.lastname: Hidalgo
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain.
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Quesada
authors.affiliation: Microbiology Service, Germans Trias i Pujol University Hospital, Department of Genetics and Microbiology, Autonomous University of Barcelona, Badalona, Spain CIBER in Respiratory Diseases (CIBERES), Madrid, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Ausina
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008828:Microbiological Techniques / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014552:Urinary Tract Infections / Q000175:diagnosis*; D014556:Urine / Q000382:microbiology*
references.citation: Enferm Infecc Microbiol Clin. 2015 Feb;33(2):89-94
references.pmid: 24796945
references.citation: Clin Microbiol Infect. 2014 Jul;20(7):O421-7
references.pmid: 24237623
references.citation: BMC Microbiol. 2015;15:124
references.pmid: 26084329
references.citation: Enferm Infecc Microbiol Clin. 2015 Jun-Jul;33(6):372-8
references.pmid: 25444360
references.citation: Eur J Clin Microbiol Infect Dis. 2015 Sep;34(9):1787-95
references.pmid: 26054715
references.citation: J Med Microbiol. 2015 Jun;64(6):605-9
references.pmid: 25855757
references.citation: J Med Microbiol. 2015 Nov;64(11):1346-52
references.pmid: 26361761
references.citation: Diagn Microbiol Infect Dis. 2014 Nov;80(3):193-6
references.pmid: 25139844
references.citation: J Clin Microbiol. 1976 Oct;4(4):372-4
references.pmid: 61972
references.citation: Med Clin (Barc). 2008 Apr 12;130(13):481-6
references.pmid: 18423165
references.citation: Clin Infect Dis. 2009 Aug 15;49(4):543-51
references.pmid: 19583519
references.citation: Diagn Microbiol Infect Dis. 2009 Oct;65(2):103-7
references.pmid: 19748419
references.citation: J Clin Microbiol. 2010 Feb;48(2):444-7
references.pmid: 19955282
references.citation: J Clin Microbiol. 2010 Jun;48(6):2110-5
references.pmid: 20392910
references.citation: Clin Microbiol Infect. 2011 Apr;17(4):546-51
references.pmid: 20456452
references.citation: Med Decis Making. 2011 May-Jun;31(3):405-11
references.pmid: 21191120
references.citation: Eur J Clin Microbiol Infect Dis. 2012 Mar;31(3):311-7
references.pmid: 21698496
references.citation: Clin Lab. 2012;58(1-2):107-11
references.pmid: 22372352
references.citation: J Microbiol Methods. 2013 Mar;92(3):231-5
references.pmid: 23305925
references.citation: J Clin Microbiol. 2014 Jan;52(1):335-8
references.pmid: 24226916
references.citation: Am J Clin Pathol. 2014 Feb;141(2):204-12
references.pmid: 24436267
references.citation: PLoS One. 2014;9(1):e86915
references.pmid: 24466289
references.citation: J Clin Microbiol. 2014 Jul;52(7):2521-9
references.pmid: 24808235
references.citation: Nat Rev Microbiol. 2015 May;13(5):269-84
references.pmid: 25853778