Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.
Department of Clinical Microbiology, Karolinska University Hospital, Huddinge, SE 141 86, Stockholm, Sweden.
Eur J Clin Microbiol Infect Dis. 2020 Jan;39(1):139-149. doi: 10.1007/s10096-019-03703-y. Epub 2019 Oct 22.
Rapid identification and antimicrobial susceptibility testing remain a crucial step for early efficient therapy of bloodstream infections. Traditional methods require turnaround times of at least 2 days, while rapid procedures are often associated with extended hands-on time. The Accelerate Pheno™ System provides microbial identification results within 90 min and susceptibility data in approximately 7 h directly from positive blood cultures with only few minutes of hands-on time. The aim of this study was, therefore, to evaluate the performance of the Accelerate Pheno™ System in identification and antimicrobial susceptibility testing of both Gram-positive and Gram-negative bacteria directly from clinical blood culture samples. We analyzed 108 and 67 blood culture bottles using the Accelerate PhenoTest™ BC kit with software version v1.0 and the FDA-cleared version v1.2, respectively. Reliable identification was achieved for Enterobacteriaceae, staphylococci, and enterococci, with 76/80 (95%), 42/46 (91%), and 10/11 (91%) correct identifications. Limitations were observed in the identification of streptococci, including Streptococcus pneumoniae and Streptococcus pyogenes, and coagulase-negative staphylococci. Antimicrobial susceptibility results for Enterobacteriaceae, for amikacin, ertapenem, ciprofloxacin, gentamicin, meropenem, and piperacillin-tazobactam ranged between 86 and 100% categorical agreement. Using v1.2, results for ceftazidime showed 100% concordance with the reference method. For staphylococci, the overall performance reached 92% using v1.2. Qualitative tests for detection of methicillin or macrolide-lincosamide-streptogramin B (MLSB) resistance caused major and very major errors for isolates. Overall, the present data show that the Accelerate Pheno™ system can, in combination with Gram stain, be used as a rapid complementation to standard microbial diagnosis of bloodstream infections.
快速鉴定和药敏试验仍然是早期有效治疗血流感染的关键步骤。传统方法需要至少 2 天的周转时间，而快速程序通常需要更长的手动操作时间。Accelerate Pheno™ 系统可在 90 分钟内提供微生物鉴定结果，在大约 7 小时内提供药敏数据，直接从阳性血培养物中获得，仅需几分钟的手动操作时间。因此，本研究旨在评估 Accelerate Pheno™ 系统在直接从临床血培养样本中鉴定革兰氏阳性和革兰氏阴性细菌以及药敏试验方面的性能。我们分别使用 Accelerate PhenoTest™ BC 试剂盒（软件版本 v1.0 和 FDA 批准的 v1.2）分析了 108 个和 67 个血培养瓶。肠杆菌科、葡萄球菌和肠球菌的可靠鉴定率分别为 76/80（95%）、42/46（91%）和 10/11（91%）。链球菌，包括肺炎链球菌和化脓性链球菌以及凝固酶阴性葡萄球菌的鉴定存在局限性。肠杆菌科对阿米卡星、厄他培南、环丙沙星、庆大霉素、美罗培南和哌拉西林他唑巴坦的药敏结果分类符合率为 86-100%。使用 v1.2，头孢他啶的结果与参考方法完全一致。使用 v1.2，葡萄球菌的总符合率为 92%。检测耐甲氧西林或大环内酯-林可酰胺-链阳菌素 B（MLSB）耐药性的定性试验导致主要和非常大的错误率。总的来说，目前的数据表明，Accelerate Pheno™ 系统可以与革兰氏染色相结合，作为血流感染标准微生物诊断的快速补充。
