Infectious and Tropical Diseases Department, CHU de Bordeaux, Bordeaux, France; University of Bordeaux, UMR 5234 CNRS, ARMYNE, Bordeaux, France.
Department of Vascular Surgery, CHU de Bordeaux, Bordeaux, France.
J Vasc Surg. 2024 Aug;80(2):554-563.e4. doi: 10.1016/j.jvs.2024.04.015. Epub 2024 Apr 10.
Vascular graft and endograft infections (VGEIs) are complicated by high morbidity, mortality, and recurrence rates, notably due to biofilm formation on the graft surface, hardly dislodgeable by the sole anti-infectious treatment. The characteristics of this biofilm are still poorly documented. The aim of this study was to evaluate ex vivo biofilm on removed infected vascular grafts and endografts (VGEs).
Explanted VGEs were prospectively collected from 2019 to 2022 at Bordeaux University Hospital, France. Two samples per graft were used for scanning electron microscopy imaging; one was sonicated, and both grafts' sides were imaged.
A total of 26 patients were included, 18 with VGEI, eight without any infection (endoleak and/or thrombosis), and 29 VGEs were collected. Microbial documentation was obtained in 83% of VGEIs. A thick layer of fibrin was visible on almost all grafts, mixed with a dense biofilm matrix on infected grafts visible as early as 1 month after the onset of infection. Bacteria were not always visualized on infected grafts' surface (80% on outer side and 85% on luminal side) but were surprisingly present on one-third of non-infected grafts. There was no significant difference between biofilm, fibrin, and microorganisms' distribution between the two grafts' sides. However, there were clear differences between infected and non-infected grafts, since immune cells, bacteria and biofilm were more frequently visualized on both sides of infected grafts (P < .05). Bacteria and immune cells although still visible, were significantly less present after sonication; the number of other elements including biofilm was not significantly different.
The persistence of a thick layer of fibrin and biofilm embedding microorganisms on both sides of infected VGE even after 1 month of infection could be the explanation for the low success rates of conservative management and the usual need for graft removal to treat VGEIs.
血管移植物和血管内移植物感染（VGEI）发病率、死亡率和复发率高，这主要是由于移植物表面形成生物膜，仅通过抗感染治疗很难清除。生物膜的特征仍未得到充分记录。本研究旨在评估从法国波尔多大学医院取出的感染血管移植物和血管内移植物（VGE）的体外生物膜。
前瞻性收集了 2019 年至 2022 年在法国波尔多大学医院的 VGE 感染患者的 VGE。每个移植物使用两个样本进行扫描电子显微镜成像；一个样本进行超声处理，两个移植物的侧面都进行成像。
共纳入 26 例患者，18 例为 VGEI，8 例无任何感染（内漏和/或血栓形成），共收集 29 个 VGE。83%的 VGEI 患者获得了微生物学证据。几乎所有移植物上都可见一层厚厚的纤维蛋白，感染移植物上可见一层密集的生物膜基质，感染后 1 个月即可观察到。感染移植物表面并不总是能看到细菌（80%的外侧面和 85%的内腔面），但令人惊讶的是，三分之一的非感染移植物上存在细菌。生物膜、纤维蛋白和微生物在两个移植物侧面的分布无显著差异。然而，感染和非感染移植物之间存在明显差异，因为在感染移植物的两面都更频繁地观察到免疫细胞、细菌和生物膜（P <.05）。尽管超声处理后仍能观察到细菌和免疫细胞，但它们的存在明显减少；生物膜等其他元素的数量无显著差异。
感染 VGE 后 1 个月，即使在感染的 VGE 两侧仍存在厚厚的纤维蛋白层和嵌入微生物的生物膜，这可能是保守治疗成功率低以及通常需要移植物切除来治疗 VGEI 的原因。
