MALDI-TOF Mass Spectrometry as efficient as multi-locus sequencing for identification Aspergilli

A. Alanio, JL Beretti, B. Dauphin, E. Mellado, G. QuesnesA. Amara, Nassif X., ME Bougnoux

Abstract: 

Introduction: Current identification of Aspergilli based on morphological characteristics fails to detect emerging species Recently Described by using multi-locus sequencing (MLS). Such identification is significant Because of different patterns of antifungal drug susceptibility. We postulate That MALDI-TOF Mass Spectrometry (MS), as in bacterial species identification, can aussi discriminate species of Aspergillus .

Methods: A set of reference strains Belonging to 24 Clinically Relevant Was species used to build a reference database, as Previously Described (J.Clinical.Microbiol, 45, 2156.). To Identify specific species discriminating peaks, the profile of early (<2 days) and late (> 4 d.) Spores Were Analyzed For Each referenced strain. The spectra of 120 clinical isolates and 16 environmental, APPROBATION with MLS (beta-tubulin and calmodulin) Were Compared To That of Each of the 28 reference strains as Follows: 50 A. fumigatus , 7 A. lentulus , 5Neosartorya pseudofischeri , 2 A. viridinutans and A. hiratsukae , A. fumigatiaffinis , 1 A. fumisynnematus , N.fischeri and N. udagawae (section Fumigati ); 13 A. flavus , 2 A. tamarii , 1 A. parvisclerotigenus (s. Flavi ); 8 A. terreus (s. Terrei ) 9 A. Niger , 2 A. foetidus , 1 A. tubengensis (s. Nigri ) 4 Emericella nidulans , 1 E.quadrilineata , 7 A. sydowii , 3 A. versicolor (s. Nidulantes ); 11 A. calidoustus , 1 A. pseudodeflectus , 1 A.insuetus (s. Usti ); A. ochraceus (s. Circumdati ).

Results: Using our database, proper identification Was in 134 of 136 isolates (98.4%): 69 of 71 (98%) from section Fumigati , 16 of 16 (100%) from Flavi , 8 of 8 (100%) from Terrei , 12 of 12 (100%) from Nigri , 15 of 15 (100%) from Nidulantes , and 13 of 13 (100%) from Usti .

Conclusion: MALDI-TOF-MS is a Powerful tool for rapid identification of relevant species of Aspergillus,Including Those That emerging can not be APPROBATION Actually by microscopic examination.

2009

Full conference title: 

Réunion Interdisciplinaire de Chimiothérapie Anti Infectieuse
    • RICAI 29th (2009)