Department of Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, Texas.
Department of Surgery, Baylor College of Medicine, Houston, Texas.
J Surg Res. 2022 Mar;271:73-81. doi: 10.1016/j.jss.2021.10.010. Epub 2021 Nov 27.
As more left ventricular-assist devices (LVADs) are implanted, multidrug-resistant LVAD infections are becoming increasingly common, partly due to bacterial biofilm production. To aid in developing bacteriophage therapy for LVAD infections, we have identified the most common bacterial pathogens that cause LVAD driveline infections (DLIs) in our heart transplant referral center.
We studied a retrospective cohort of patients who received LVADs from November 2003 to August 2017 to identify the common causative organisms of LVAD infection. We also studied a prospective cohort of patients diagnosed with DLIs from October 2018 to May 2019 to collect bacterial strains from DLIs for developing bacteriophages to lyse causative pathogens. LVAD infections were classified as DLI, bacteremia, and pump/device infections in the retrospective cohort.
In the retrospective cohort of 582 patients, 186 (32.0%) developed an LVAD infection, with 372 microbial isolates identified. In the prospective cohort, 96 bacterial strains were isolated from 54 DLIs. The microorganisms causing DLIs were similar in the two cohorts; the most common isolate was Staphylococcus aureus. We identified 6 prospective S. aureus strains capable of biofilm formation. We developed 3 bacteriophages that were able to lyse 5 of 6 of the biofilm-forming S. aureus strains.
Similar pathogens caused LVAD DLIs in our retrospective and prospective cohorts, indicating our bacterial strain bank will be representative of future DLIs. Our banked bacterial strains will be useful in developing phage cocktails that can lyse ≥80% of the bacteria causing LVAD infections at our institution.
随着越来越多的左心室辅助装置（LVAD）被植入，多药耐药性 LVAD 感染变得越来越常见，部分原因是细菌生物膜的产生。为了帮助开发针对 LVAD 感染的噬菌体疗法，我们已经确定了我们心脏移植转诊中心导致 LVAD 驱动线感染（DLIs）的最常见细菌病原体。
我们研究了一组接受 LVAD 的回顾性队列患者，以确定 LVAD 感染的常见病原体。我们还研究了一组从 2018 年 10 月至 2019 年 5 月被诊断为 DLI 的前瞻性队列患者，以收集 DLI 中的细菌株，用于开发裂解致病病原体的噬菌体。在回顾性队列中，LVAD 感染分为 DLI、菌血症和泵/装置感染。
在 582 例患者的回顾性队列中，186 例（32.0%）发生 LVAD 感染，共鉴定出 372 株微生物分离株。在前瞻性队列中，从 54 例 DLI 中分离出 96 株细菌株。两个队列中导致 DLI 的微生物相似，最常见的分离株是金黄色葡萄球菌。我们鉴定出 6 株能够形成生物膜的潜在金黄色葡萄球菌菌株。我们开发了 3 种噬菌体，能够裂解 5 株 6 株形成生物膜的金黄色葡萄球菌菌株。
在我们的回顾性和前瞻性队列中，导致 LVAD DLI 的病原体相似，这表明我们的细菌株库将代表未来的 DLI。我们的细菌株库将有助于开发噬菌体鸡尾酒，能够裂解我们机构中导致 80%以上 LVAD 感染的细菌。
