[Identification of zoonotic bacterial pathogens by the MALDI TOF MS method].

Objective: To verify whether the MALDI TOF MS method can be used for rapid identification of selected zoonotic bacterial pathogens isolated from various types of materials in the real conditions of routine laboratory work.

Material And Methods: Between August 2010 and April 2015, the Bruker's MALDI TOF MS system was used for 4,174 identifications of selected zoonotic bacterial pathogens (Salmonella spp., Campylobacter jejuni, Campylobacter coli, Listeria monocytogenes, Yersinia enterocolitica, Yersinia pseudotuberculosis, Francisella tularensis, Brucella melitensis, Brucella suis and Cronobacter sakazakii). The samples were prepared for the test by simply mixing a bacterial culture with a matrix on a steel target plate. The results were evaluated with a standard protocol of the system using the MALDI Biotyper software under operating conditions.

Results: In 74.8 % of the tested isolates of the above bacterial species, the identification scores ranged between 2 and 3, which is satisfactory for result interpretation in routine practice. Acceleration of identification of Campylobacter spp. and Listeria monocytogenes by testing suspicious cultures obtained directly from selective-diagnostic media decreased the identification scores in these cases.

Conclusion: MALDI TOF MS is a suitable and rapid method for identification of the selected zoonotic bacterial pathogens.