[MALDI-TOF mass spectrometry to identify clinical bacterial isolates: evaluation in a teaching hospital in Lille].
OBJECTIVE
The aim of our study was to evaluate the capacity of MALDI-TOF mass spectrometry to identify clinical bacterial isolates, as compared to the automated identification system Vitek 2 (bioMérieux) used routinely in a teaching hospital.


METHODS
Three hundred and sixty-two strains representing 178 species from the laboratory collection were analysed by a Microflex spectrometer (Bruker Daltonics) and Vitek 2. Discrepancies between MALDI-TOF and Vitek 2 identifications were investigated by genetic identification (rrS, sodA, rpoB), considered as a reference.


RESULTS
Among the 362 isolates, 264 (73%) were consistently identified by Vitek 2 and Microflex. Taking into account genetic identification, we found that 44 (44.9%) of the 98 remaining isolates were correctly identified by mass spectrometry but not by Vitek 2. Conversely, 33 isolates (33.7%) were correctly identified by Vitek 2, but not by Microflex. The genetic identification of the 21 remaining isolates (21,4%) did not match either Vitek 2 or Microflex results.


CONCLUSIONS
The performances of MALDI-TOF mass spectrometry for bacterial identification correspond to those of a reference automated identification system.
Blondiaux
N
N
Pôle de Microbiologie, Centre de Biologie Pathologie, Centre Hospitalier Régional Universitaire de Lille, boulevard du Pr-J-Leclercq, 59037 Lille cedex, France. nicolas.blondiaux@chru-lille.fr
Gaillot
O
O
Courcol
R-J
RJ
D001419:Bacteria / Q000145:classification* / Q000235:genetics; D001424:Bacterial Infections / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques / Q000295:instrumentation / Q000379:methods*; D004269:DNA, Bacterial / Q000235:genetics; D005602:France; D005798:Genes, Bacterial; D005838:Genotype; D006785:Hospitals, University; D006801:Humans; D010641:Phenotype; D012015:Reference Standards; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013997:Time Factors
D001426:Bacterial Proteins; D004269:DNA, Bacterial