2022年,临床和实验室标准研究所(CLSI)更新了肠杆菌的哌拉西林-他唑巴坦(TZP)断点,基于大量数据,表明历史断点不能预测TZP的治疗结果。美国食品和药物管理局(FDA)尚未采用这些断点,这意味着抗菌药物敏感性测试设备的商业制造商无法获得FDA修订断点的许可。我们评估了凤凰号(BD,火花,MD),MicroScan(BeckmanCoulter,萨克拉门托,CA),和Vitek2(bioMérieux,达勒姆,NC)TZPMIC与参考肉汤微量稀释相比,收集了284种肠杆菌分离株。凤凰城(n=167个分离株)表现出84.4%的分类一致性(CA),根据CLSI断点,4.2%的非常大错误(VME)和1.8%的主要错误(ME)。相比之下,对于具有FDA断点的凤凰城,CA为85.0%,VME为4.3%,ME为0.8%。MicroScan(n=55个分离株)显示80.0%CA,36.4%的VME,和4.8%的CLSI断点和81.8%的CA,44.4%的VME,和0.0%的MEs按FDA断点计算。Vitek2(n=62个分离株)显示95.2%CA,6.3%的VME,和0.0%的CLSI和96.8%的CA,0.0%VME,和2.2%的MEs按FDA断点计算。总的来说,使用标签外CLSI断点与使用标签上FDA断点的测试系统的性能没有实质性差异.然而,VME率高于预期(所有三个系统),CA低于预期(MicroScan和Phoenix)。实验室应考虑采用修订的CLSI断点与自动测试系统,但要注意,在自动化系统上测试TZP存在一些性能挑战。无论应用的断点。
In 2022, the Clinical and Laboratory Standards Institute (CLSI) updated piperacillin-tazobactam (TZP) breakpoints for Enterobacterales, based on substantial data suggesting that historical breakpoints did not predict treatment outcomes for TZP. The U.S. Food and Drug Administration (FDA) has not yet adopted these breakpoints, meaning commercial manufacturers of antimicrobial susceptibility testing devices cannot obtain FDA clearance for the revised breakpoints. We evaluated the Phoenix (BD, Sparks, MD), MicroScan (Beckman Coulter, Sacramento, CA), and
Vitek2 (bioMérieux, Durham, NC) TZP MICs compared to reference broth microdilution for a collection of 284 Enterobacterales isolates. Phoenix (n = 167 isolates) demonstrated 84.4% categorical agreement (CA), with 4.2% very major errors (VMEs) and 1.8% major errors (MEs) by CLSI breakpoints. In contrast, CA was 85.0% with 4.3% VMEs and 0.8% MEs for the Phoenix with FDA breakpoints. MicroScan (n = 55 isolates) demonstrated 80.0% CA, 36.4% VMEs, and 4.8% MEs by CLSI breakpoints and 81.8% CA, 44.4% VMEs, and 0.0% MEs by FDA breakpoints.
Vitek2 (n = 62 isolates) demonstrated 95.2% CA, 6.3% VMEs, and 0.0% MEs by CLSI and 96.8% CA, 0.0% VMEs, and 2.2% MEs by FDA breakpoints. Overall, the performance of the test systems was not substantially different using CLSI breakpoints off-label than using on-label FDA breakpoints. However, limitations were noted with higher-than-desired VME rates (all three systems) and lower-than-desired CA (MicroScan and Phoenix). Laboratories should consider adoption of the revised CLSI breakpoints with automated test systems but be aware that some performance challenges exist for testing TZP on automated systems, regardless of breakpoints applied.