Development and Evaluation of Novel Applied Diagnostic Platforms for Clinical Microbiology

传统的微生物工作是缓慢的，有时是不准确的，依靠表型培养鉴定，然后进行抗菌药物敏感性试验。较新的技术，如基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）和实时分子检测（抗微生物基因微阵列），提高了临床微生物实验室的诊断能力，并创造了一个令人兴奋的研究和发展领域。鉴于这些平台产生的深入和高度准确（有时是复杂的）结果，需要进行仔细详细的分析，以更好地了解所鉴定的生物体的临床意义和检测到的耐药机制。

Traditional microbiological work up is slow and sometimes inaccurate, relying on phenotypic culture identification followed by antimicrobial susceptibility testing. Newer technologies, such as matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and real-time molecular detection (antimicrobial resistance genes microarrays) have advanced the diagnostic capabilities of clinical microbiology laboratories and have created an exciting field for research and development. Given the in-depth and highly accurate (sometimes complex) results that are produced by such platforms, careful detailed analyses are required to better understand the clinical significance of the organisms identified and the resistance mechanisms detected. During this fiscal year, we performed a large retrospective analysis on the clinical performance of HardyCHROM CRE media for the detection of carbapenemase-producing organisms from surveillance cultures. Data showed a positive predictive value ranging 8-56% depending on the definition carbapenem resistant organisms applied which varies between states and national guidelines. This has a tremendous effect on applied infection control practices and antimicrobial choices in response to a potential clinical infection. We also performed a comparative evaluation of three phenotypic assays for the detection of carbapenemases, as well as a retrospective analysis on the performance and accuracy of MALDI-TOF MS and susceptibility testing directly from positive blood cultures. The latter has provided informative results for clinical microbiology reporting while awaiting standardized testing results. Quality improvement projects have included a prospective comparative evaluation of blood culture volume monitoring methods (weight vs virtual system), comparative analysis of a multiplex gastrointestinal pathogen panel with traditional methods, and a large comparative assessment of product sterility testing systems for novel therapies (traditional USP<71> manual method vs automated Bactec FX system and BacTAlert Dual-T system).