Microbiology Service, Hospital Clínico Universitario, Instituto de Investigación INCLIVA, Valencia, Spain.
Infectious Diseases Unit, Hospital Clínico Universitario, Instituto de Investigación INCLIVA, Valencia, Spain.
J Infect Chemother. 2020 Sep;26(9):963-969. doi: 10.1016/j.jiac.2020.04.019. Epub 2020 May 5.
To assess the potential added value of rapid MALDI-TOF MS-based identification of bacteria in positive blood cultures to the information provided by Gram staining for adequate empirical antibiotic treatment adjustments in patients with bloodstream infections (BSI).
We conducted a retrospective, single-center, pre-post quasi-experimental study. In the pre-MALDI-TOF MS phase of the study antibiotic adjustments were made on the basis of Gram stain results, whereas in the MALDI-TOF MS phase they were based on information provided by Gram staining and MALDI-TOF MS results. No antimicrobial stewardship program for BSI was in place within the study period. Antibiotic regimens were categorized as correct, improvable or incorrect.
Cohorts were matched for demographics, clinical characteristics of patients and bacterial species involved. Enterobacteriales were the most represented in both study periods (67%), followed by Non-fermenting Gram-negative bacilli and Gram-positive cocci. The number of patients receiving correct, improvable and incorrect empirical antibiotic treatments was comparable for both study periods (P = 0.45, P = 0.57, P = 0.87, respectively). The percentage of patients who ended up receiving correct treatment following modified empirical antibiotic regimens was significantly higher (P = 0.008) in the MALDI-TOF MS phase (27 patients/38.6%) than in the pre-MALDI-TOF MS phase of the study (11 patients/15.7%), although overall adequate coverage of the bacteria causing the infection was comparable across the study periods (90%).
Gram stain results offer valuable information for early adjustment of empirical antibiotic therapies for BSI. Nevertheless, rapid identification of bacteria involved in BSI by MALDI-TOF MS provides added value to achieve this aim.
评估快速基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）对血培养阳性标本中细菌鉴定的潜在附加值，以帮助临床医生在血流感染（BSI）患者中根据革兰氏染色结果及时调整经验性抗生素治疗方案。
我们进行了一项回顾性、单中心、前后准实验研究。在 MALDI-TOF MS 前阶段，根据革兰氏染色结果调整抗生素；而在 MALDI-TOF MS 阶段，根据革兰氏染色和 MALDI-TOF MS 结果提供的信息调整抗生素。在研究期间，未实施任何针对 BSI 的抗菌药物管理计划。将抗生素方案分为正确、可改进和不正确。
两个研究阶段的患者人口统计学、临床特征和细菌种类均匹配。肠杆菌目（Enterobacteriales）在两个研究阶段均占比最高（67%），其次是非发酵革兰氏阴性杆菌和革兰氏阳性球菌。两个研究阶段接受正确、可改进和不正确经验性抗生素治疗的患者数量相当（P=0.45，P=0.57，P=0.87）。经改良经验性抗生素方案治疗后，最终接受正确治疗的患者比例在 MALDI-TOF MS 阶段（27 例/38.6%）显著高于 MALDI-TOF MS 前阶段（11 例/15.7%）（P=0.008），尽管两个研究阶段的总体感染细菌覆盖情况相当（90%）。
革兰氏染色结果为早期调整 BSI 的经验性抗生素治疗提供了有价值的信息。然而，MALDI-TOF MS 快速鉴定 BSI 中的细菌为实现这一目标提供了附加价值。
