Tieszer C, Reid G, Denstedt J
Department of Microbiology and Immunology, The University of Western Ontario, London, Canada.
J Biomed Mater Res. 1998 Fall;43(3):321-30. doi: 10.1002/(sici)1097-4636(199823)43:3<321::aid-jbm14>3.0.co;2-i.
Ureteral stents are commonly implanted to assist the postsurgery flow of urine from the kidney to the bladder. We hypothesized that different surface compositions of stent material could result in different conditioning film depositions and potentially altered receptivity to bacterial biofilms. Using XPS, three types of ureteral stents recovered from 64 patients were found to have adsorbed conditioning films that altered the surface composition of the devices. Elements associated with encrustation (calcium, magnesium and phosphorus) were found on 69% of the silicone latex stents, 44% of the low surface energy (LSe) devices, and 38% of the carbon-rich stents. No statistical difference was found in relation to patient gender, stent type, duration of implantation, and encrustation deposition. The composition of the film suggested that the nature of the underlying material did not significantly alter the elements that adsorbed. Thus, devices may take on a similar surface coat within days, and perhaps hours, of exposure to the host. With respect to dense encrustations, fewer appeared on the LSe devices. SEM confirmed the presence and nature of the film crystals and showed bacterial biofilms adherent to devices and encrustations in three patients who had received prophylactic trimethoprim compared to one on ciprofloxacin. In conclusion, although encrustation deposition and biofilm formation on ureteral stents is not unique to Cook devices, the human model and surface science test systems described here are invaluable to evaluate biomaterials used in patients. Unless biomaterials undergo rigorous analysis in vivo, including true assessment of the outcome of prophylactic antibiotic usage, clinicians will be unable to accurately select the best device and management strategy for a given patient.
输尿管支架通常被植入以辅助术后尿液从肾脏流向膀胱。我们推测，支架材料的不同表面成分可能导致不同的调理膜沉积，并可能改变对细菌生物膜的接受性。使用X射线光电子能谱（XPS），从64名患者体内回收的三种类型的输尿管支架被发现吸附了调理膜，这些调理膜改变了装置的表面成分。在69%的硅橡胶乳胶支架、44%的低表面能（LSe）装置和38%的富碳支架上发现了与结石形成相关的元素（钙、镁和磷）。在患者性别、支架类型、植入持续时间和结石沉积方面未发现统计学差异。膜的成分表明，底层材料的性质并没有显著改变吸附的元素。因此，装置在暴露于宿主后的数天甚至数小时内可能会形成类似的表面涂层。关于致密结石，在LSe装置上出现的较少。扫描电子显微镜（SEM）证实了膜晶体的存在和性质，并显示在三名接受预防性甲氧苄啶治疗的患者中，与一名接受环丙沙星治疗的患者相比，细菌生物膜附着在装置和结石上。总之，虽然输尿管支架上的结石沉积和生物膜形成并非Cook装置所特有，但本文描述的人体模型和表面科学测试系统对于评估用于患者的生物材料非常宝贵。除非生物材料在体内经过严格分析，包括对预防性抗生素使用结果的真实评估，否则临床医生将无法准确为特定患者选择最佳的装置和管理策略。
