Evaluation of two MALDI-TOF MS systems and extraction methods for identification of filamentous fungi recovered from clinical specimens

作者：Eric M. Ransom, Meghan A. Wallace, Nathan P. Wiederhold, Connie Cañete‐Gibas, Carey‐Ann D. Burnham · 发表于：Journal of Clinical Microbiology · 年份：2025 · DOI：10.1128/jcm.01548-24 · 被引用次数：8 · 研究领域：Bacterial Identification and Susceptibility Testing、Plant Pathogens and Fungal Diseases、Diphtheria, Corynebacterium, and Tetanus

ABSTRACT Rapid and accurate identification of cultured molds is important to determine clinical significance and therapeutic decision-making. Conventional mold identification uses phenotypic macroscopic and microscopic characterization; however, this can take days or weeks for colony maturity and definitive microscopic structure formation, be limited to genus-level identification, and be misidentified due to morphologic mimics or similarities between closely related species. Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI–TOF MS) revolutionized bacterial and yeast identification but remains uncommon for molds in part because of limited reference libraries. Here, a retrospective 5-year review at a large teaching hospital found that 88.6% of identified molds were in the Bruker Filamentous Fungi Library 3.0 and 91.5% in the VITEK Knowledge Base Library 3.2.0. A prospective evaluation was also performed on early growth from 205 consecutive, working clinical isolates. Each mold was processed using the VITEK chemical extraction method and modified NIH chemical plus bead-beating extraction method; both extractions were tested on both systems. When compared to conventional identification, more molds were identified using VITEK extractions over NIH extractions using the VITEK (65 and 59%) and Bruker (56 and 54%) systems, respectively, using the ≥1.5 log Bruker threshold. VITEK MS identified more molds, regardless of the extraction method. Isolates w...