Multicenter Studies to Evaluate the Performance of MALDI-TOF MS for Fungal Identification

传统的霉菌鉴定具有挑战性，繁琐且耗时，依赖于培养物的非特异性表型特征或昂贵且专业的DNA测序方法。MALDI-TOF MS彻底改变了全球临床微生物实验室，使细菌和酵母菌的快速鉴定成为可能。然而，由于开发有效的蛋白质提取方法的技术挑战和临床综合数据库的有限可用性，该技术尚未容易地应用于霉菌鉴定。 最近，我们开发和优化了一个简单的蛋白质提取程序的模具，并构建了一个高度严格的数据库，包括410个单独的菌株，代表90个属和220个种的快速鉴定霉菌的MALDI-TOF MS。美国国立卫生研究院霉菌数据库是最全面的数据库开发到目前为止的霉菌鉴定，填补了巨大的诊断空白，在临床微生物学领域。NIH霉菌数据库现已与全球超过100个临床微生物学实验室共享，旨在通过提供更快的鉴定（在生长检测的30分钟内，而不是数周）来改善侵袭性真菌感染的诊断，从而指导最佳的抗真菌治疗。 在本财政年度，进行了一项八中心国家对照研究，以评估两个真菌数据库（NIH霉菌数据库和布鲁克真菌数据库）对80种临床霉菌分离株的临床性能和准确性。此外，与另一家美国机构开展了一个合作项目，以研究不同培养条件（培养基、孵育时间、固体与液体培养基）对两个真菌数据库的影响。这两项研究正在进行中，预计研究结果将突出强调全球临床微生物实验室统一实施MALDI-TOF MS进行常规霉菌鉴定所需的重要（以前未确定）因素。这反过来将使侵袭性真菌感染的诊断和靶向治疗策略更快。

Traditional identification of molds is challenging, cumbersome, and time-consuming, relying on non-specific phenotypic characteristics from culture or expensive and specialized DNA sequencing methods. MALDI-TOF MS has revolutionized clinical microbiology laboratories worldwide, enabling rapid identification of bacteria and yeast. This technology, however, has not been readily applied to mold identification due to technical challenges in developing an efficient protein extraction method and the limited availability of clinically comprehensive databases. Recently, we developed and optimized a simple protein extraction procedure for molds and constructed a highly stringent database comprising 410 individual isolates representing 90 genera and 220 species for the rapid identification of molds by MALDI-TOF MS. The NIH Mold Database is the most comprehensive database developed to date for mold identification and has filled a huge diagnostic gap in the field of clinical microbiology. The NIH Mold Database has now been shared with >100 clinical microbiology laboratories worldwide in an effort to improve the diagnosis of invasive fungal infections by providing faster identification (within 30 minutes of growth detection as opposed to weeks) that in turn can guide optimal antifungal therapy. During this fiscal year, an eight-center national controlled study was undertaken to evaluate the clinical performance and accuracy of two fungal databases (the NIH Mold Database and the Bruker Fungi Database) against 80 clinical mold isolates. In addition, a collaborative project was undertaken with another US institution to investigate the effects of different culture conditions (media, time of incubation, solid vs. liquid media) against both fungal databases. Both studies are ongoing and it is envisaged that the findings will highlight important (previously undetermined) factors required for the uniform implementation of MALDI-TOF MS for the routine mold identification in clinical microbiology laboratories worldwide. This in turn will enable faster diagnosis and targeted therapeutic strategies for invasive fungal infections.