Xenophilus aerolatus isolate misidentified as Brucella spp. by MALDI-TOF MS (VITEK-MS) system.

We report the characterization of Xenophilus aerolatus strain identified from a screening rectal swab specimen in human, initially misidentified as Brucella spp. by MALDI-TOF MS (VITEK-MS system). The strain is able to growth on Colorex mSuperCARBA plate, suggesting carbapenem resistance.

Performance of common primary and chromogenic culture media for MALDI-TOF MS identification of clinically relevant yeasts.

Timely and accurate identification of yeasts is essential for adequate treatment, considering the increase in antifungal resistance of some species, particularly for . Current matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) manufacturer's protocol for identification of yeasts requires 24- to 72-h cultivation on Sabouraud dextrose media (SAB), but not some of the mainstay primary culture media used in mycology such as inhibitory mold agar (IMA), Mycosel, CHROMagar Candida Plus, and CHROMagar Candida. As culture media can influence MALDI-TOF MS identification results, this study evaluated the accuracy and performance of identification of clinically relevant yeasts on these first-line media using the VITEK-MS MALDI-TOF MS system.