Microbiology Unit, Foch Hospital, France.
Infectious Disease Unit and Internal Medicine Unit, Foch Hospital, France.
Infect Dis Now. 2022 Nov;52(8):421-425. doi: 10.1016/j.idnow.2022.09.002. Epub 2022 Sep 13.
During bloodstream infections, reducing the time to antimicrobial susceptibility testing is crucial to initiation of early appropriate antibiotic therapy. For Gram-negative infections, a phenotypic approach remains necessary. Rapid antimicrobial testing (RAST) is a recently developed phenotypic EUCAST method. The goal of this study was to evaluate the accuracy and clinical impact of RAST.
From September 2020 to August 2021, Gram-negative episodes with positive blood culture detected in the morning were included in the RAST group. Categorical agreement of RAST with conventional antimicrobial testing on strains was determined. To assess antibiotic management and patient outcomes, the RAST group was compared with a control group (CG) with positive blood culture detected in the afternoon for which overnight antimicrobial testing was performed.
The RAST group included 61 episodes from 61 patients, while the CG group included 49 episodes from 48 patients. While RAST performed on 41 E. coli, 11 K. pneumoniae and 9 P. aeruginosa strains highlighted 99.3 % of categorical agreement, 7.4 % of unreadable zones and 9.4 % of technical uncertainty area at 4 h incubation were also reported. For the RAST group, effective antibiotic therapy was prescribed in 100 % of patients on the day of positive blood culture (day 1) vs 88 % in CG (p = 0,007). As for beta-lactams on day 1, RAST led to 9 escalations and 6 de-escalations. Mortality and length of hospital stay did not significantly differ between the two groups.
RAST improves management of antibiotic therapy in patients with Gram-negative sepsis.
血流感染时，缩短药敏试验时间对于启动早期适当的抗生素治疗至关重要。对于革兰氏阴性感染，仍需要表型方法。快速抗菌检测（RAST）是一种新开发的表型 EUCAST 方法。本研究旨在评估 RAST 的准确性和临床影响。
从 2020 年 9 月到 2021 年 8 月，将早晨检出革兰氏阴性菌血培养阳性的患者纳入 RAST 组。确定 RAST 与常规抗菌检测在菌株上的分类一致性。为了评估抗生素管理和患者结局，将 RAST 组与下午检出阳性血培养的对照组（CG）进行比较，对照组在夜间进行抗菌检测。
RAST 组包括 61 例患者的 61 个病例，CG 组包括 49 例患者的 49 个病例。RAST 对 41 株大肠埃希菌、11 株肺炎克雷伯菌和 9 株铜绿假单胞菌进行检测，其分类一致性为 99.3%，4 小时孵育时，不可读区为 7.4%，技术不确定区为 9.4%。在 RAST 组，100%的患者在血培养阳性的当天（第 1 天）接受了有效的抗生素治疗，而 CG 组为 88%（p=0.007）。第 1 天，β-内酰胺类药物的 RAST 导致 9 次升级和 6 次降级。两组死亡率和住院时间无显著差异。
RAST 改善了革兰氏阴性菌败血症患者的抗生素治疗管理。
