Identification of previously unknown bacterial species by MALDI-TOF MS 1 Isala, Zwolle, NL 2 Meander MC, Amersfoort, NL ECCMID 2017 - EV0223 3 Rijnstate, Velp, NL 1 2 3 1 [email protected] Marjan J. Bruins , Eric (H) S. Doppenberg , Niels Peterse , Maurice J.H.M. Wolfhagen Introduction Results Discussion In clinical microbiology, MALDI-TOF MS Many new bacteria were identified by MALDI-TOF MS (Table 1). Using MALDI-TOF MS results in: has become an important means of - Far easier and faster identification. bacterial identification, enabling faster Table 1. Examples of previously unknown species identified by MALDI-TOF. - Identification of more and previously reporting of culture results. unknown pathogens. Species Family Isolated from Reference - Identification of relevant micro- The database entries used in MALDI-TOF Gramnegative Achromobacter spanius organisms previously considered MS are based on 16S rRNA gene Alcaligenaceae blood, tissue, wound Int. J. Syst. Evol. Microbiol. 53:1823 Acidovorax temperans Comamonadaceae urine, oral cavity Int. J. Syst. Bacteriol. 40:396 commensal. sequencing, which makes this technique Bifidobacterium scardovii Bifidobacteriaceae blood, urine Int. J. Syst. Evol. Microbiol. 52:998 - A need for standardized antimicrobial more discriminatory than biochemical Campylobacter lanienae Campylobacteraceae stool Int. J. Syst. Evol. Microbiol. 50:870 Fusobacterium naviforme Fusobacteriaceae blood, abscess, oral cavity Int. J. Syst. Bacteriol. 30:302 susceptibility testing methods including methods. As a result, more pathogenic Haemophilus pittmaniae Pasteurellaceae sputum Int. J. Syst. Evol. Microbiol. 55:455 critical breakpoints for all relevant microorganisms are identified correctly than Kerstersia gyiorum Alcaligenaceae leg wounds, ear Int. J. Syst. Evol. Microbiol. 53:1830 Massilia timonae species. before and new emerging human Oxalobacteraceae blood, CSF, urine Int. J. Syst. Evol. Microbiol. 50:423 Neisseria macacae Neisseriaceae blood, ear neck abscess, eye Int. J. Syst. Bacteriol. 33:519 pathogens have been identified as well. We Ochrobactrum intermedium Brucellaceae blood, sputum, oral cavity Int. J. Syst. Bacteriol. 48:767 assessed the merit of MALDI-TOF MS Pasteurella bettyae Pasteurellaceae Bartholin cyst, wound Int. J. Syst. Bacteriol. 40:151 Pseudochrobactrum asaccharolyticum Brucellaceae knee aspirate, urine Int. J. Syst. Evol. Microbiol. 56:1826 Conclusion identifications of previously unidentifiable Streptobacillus moniliformis Leptotrichiaceae abscess rat bite Int. J. Syst. Bacteriol. 30:366 species. Wautersiella falsenii Flavobacteriaceae blood, urine, wound Int. J. Syst .Evol. Microbiol. 56:2323 Bacterial identification by MALDI-TOF MS Wohlfahrtiimonas chitiniclastica Gammaproteobacteria, blood, nail bed Int. J. Syst. Evol. Microbiol. 58:980 is not only much faster than conventional not assigned to family Materials & Methods Grampositive methods, but contributes to the detection MALDI-TOF MS results of bacterial species Actinomyces graevenitzii Actinomycetaceae blood, lung abscess Int. J. Syst. Bacteriol. 47:887. of previously unknown pathogens as well. Aerococcus sanguinicola were collected retrospectively: Aerococcaceae urine Int. J. Syst. Evol. Microbiol. 51:478 Peptoniphilus harei Peptoniphilaceae pus from sore, abscess Int. J. Syst. Evol. Microbiol. 51:1526 In an era of increasing numbers of - In three clinical microbiology laboratories Prevotella nanceiensis Prevotellaceae ear, sputum, abscess Int. J. Syst. Evol. Microbiol. 57:2219 immunocompromised patients and in the Netherlands. Streptococcus thermophilus Streptococcaceae blood, sputum Int. J. Syst. Bacteriol. 30:368 subsequent more complex bacterial - Identified by MALDI Biotyper® (Bruker). cultures, this is of great value. All "new“ isolates: - Currently not identifiable by Phoenix™ However, more research is needed to - Have been described as potential pathogens (Table 1). (BD), API® Strips or Vitek® 2 supplement standardized susceptibility - Had not been identified before by conventional biochemical methods. (bioMérieux). testing guidelines. - Were of clinical relevance to the particular patients. We studied the clinical relevance of these isolates. - Were often found in immunocompromised patients . .