Rapid species identification and differentiation of Arcobacter, Helicobacter and Campylobacter by MALDITOFMS analysis and its clinical application
Abstract number: P1799
Alispahic M., Hummel K., Jandreski-Cvetkovic D., Nöbauer K., Razzazi-Fazeli E., Hess M., Hess C.
Objectives: Identification and differentiation of species belonging to the Arcobacter, Helicobacter and Campylobacter genera has become increasingly important, since many of them are recognised as human and/or animal pathogens. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was shown to be a rapid and sensitive method for charcterisation of microorganisms. In this study, we established a reference database of selected Arcobacter, Helicobacter and Campylobacter species. The second objective was to use the reference database to identify 144 clinical isolates and compare the results to molecular method. The third objective was to evaluate the reproducibility using different growth media and age of bacteria, which are relevant in a diagnostic lab.
Methods: Besides the species with significance as food-borne pathogens Arcobacter butzleri, Helicobacter pullorum, Campylobacter jejuni and Campylobacter coli several other members of these genera were included in the reference library, grown on Columbia agar. In parallel to MALDI Biotyper 1.1 software package (Bruker Daltonik) identification, all strains were analysed by PCR-RFLP.
Results: Strains that made up for the reference database library yielded reproducible and unique mass spectra profiles, which were compared with the Bruker Biotyper database, version 2. It was found that correct identification could be obtained even if the bacteria are stored at room temperature or at +4°C up to 9 days until being tested. In addition, bacteria were correctly identified when grown on Campylosel-agar, however not when grown on modified charcoal cefoperazone deoxycholate agar. All field isolates gave sufficient spectra for species identification. In total, MALDI-TOF MS identified all 144 clinical isolates at species level.
Conclusion: Altogether, these data show that MALDI-TOF MS fingerprinting is a fast and reliable method for the identification of Arcobacter and Helicobacter species and their distinction from phenotypically similar Campylobacter species with applications in clinical diagnostics. As a result, considering the speed with which reliable identification can be obtained, this technique is well suited for large-scale research and diagnostic analyses.
|Session name:||Abstracts 20th European Congress of Clinical Microbiology and Infectious Diseases|
|Location:||Vienna, Austria, 10 - 13 April 2010|
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