Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene - Universitätsklinikum Erlangen and Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg , Erlangen, Germany.
J Clin Microbiol. 2023 Nov 21;61(11):e0054923. doi: 10.1128/jcm.00549-23. Epub 2023 Oct 11.
Adequate and timely antibiotic therapy is crucial for the treatment of sepsis. Innovative systems, like the Q-linea ASTar, have been developed to perform rapid antimicrobial susceptibility testing (AST) directly from positive blood cultures (BCs). We conducted a prospective study to evaluate ASTar under real-life conditions with a focus on time-to-result and impact on antimicrobial therapy. Over 2 months, all positive BCs that showed Gram-negative rods upon microscopy were tested with the ASTar and our standard procedure (VITEK 2 from short-term culture). Additionally, we included multidrug-resistant Gram-negative bacteria from our archive. Both methods were compared to broth microdilution. In total, 78 bacterial strains (51 prospective and 27 archived) were tested. ASTar covered 94% of the species encountered. The categorical and essential agreement was 95.6% and 90.7%, respectively. ASTar caused 2.4% minor, 2.0% major, and 2.4% very major errors. The categorical agreement was similar to standard procedure. The average time between BC sampling and the availability of the antibiogram for the attending physician was 28 h 49 min for ASTar and 44 h 18 min for standard procedure. ASTar correctly identified all patients who required an escalation of antimicrobial therapy and 75% of those who were eligible for de-escalation. In conclusion, ASTar provided reliable AST results and significantly shortened the time to obtain an antibiogram. However, the percentage of patients that will profit from ASTar in a low-resistance setting is limited, and it is currently unclear if a change of therapy 29 h after BC sampling will have a significant impact on the patient's prognosis.
及时、充分的抗生素治疗对于脓毒症的治疗至关重要。为了直接从阳性血培养物（BC）中进行快速抗菌药物敏感性测试（AST），开发了一些创新系统，如 Q-linea ASTar。我们进行了一项前瞻性研究，旨在评估 ASTar 在实际条件下的表现，重点关注结果时间和对抗菌治疗的影响。在 2 个多月的时间里，所有显微镜下显示革兰氏阴性杆菌的阳性 BC 都使用 ASTar 和我们的标准程序（来自短期培养的 VITEK 2）进行了测试。此外，我们还包括了来自我们档案的多药耐药革兰氏阴性菌。这两种方法都与肉汤微量稀释法进行了比较。总共测试了 78 株细菌（51 株前瞻性和 27 株存档）。ASTar 涵盖了 94%遇到的物种。分类和必要的一致性分别为 95.6%和 90.7%。ASTar 导致 2.4%的次要错误、2.0%的主要错误和 2.4%的非常大错误。分类一致性与标准程序相似。ASTar 从 BC 采样到主治医生获得抗生素图谱的平均时间为 28 小时 49 分钟，而标准程序为 44 小时 18 分钟。ASTar 正确识别了所有需要升级抗菌治疗的患者和 75%符合降级条件的患者。总之，ASTar 提供了可靠的 AST 结果，并显著缩短了获得抗生素图谱的时间。然而，在低耐药环境下，从 ASTar 中获益的患者比例有限，目前尚不清楚在 BC 采样后 29 小时改变治疗方案是否会对患者的预后产生重大影响。
