Bergamini T M, Bandyk D F, Govostis D, Kaebnick H W, Towne J B
Department of Surgery, Medical College of Wisconsin, Milwaukee.
J Vasc Surg. 1988 Jan;7(1):21-30.
A canine model was developed to study the efficacy of graft replacement as treatment for vascular prosthesis infections from Staphylococcus epidermidis. Infrarenal aortic graft infections were established in 18 dogs by implantation of Dacron prostheses colonized in vitro with a slime-producing strain of S. epidermidis to form an adherent bacteria-laden biofilm (5 X 10(6) colony-forming units/cm2 graft). Study animals developed a graft infection with anatomic and microbiologic characteristics typical of late prosthetic graft infections in humans (sterile perigraft exudate, absent graft incorporation, and normal serum leukocyte count and sedimentation rate). The S. epidermidis study strain was isolated from 14 of 18 explanted grafts (78%) by mechanical disruption of the graft surface biofilm and culture in broth media. Four dogs with sterile graft cultures had histologic evidence of bacterial infection. The established prosthetic surface biofilm infection was treated by graft excision, parenteral cefazolin, and graft replacement with a Dacron or polytetrafluoroethylene (PTFE) vascular prosthesis. One month after graft replacement, no PTFE graft had signs of infection, but perigraft exudate and inflammation involved three of nine Dacron grafts (33%). The study strain was recovered from four of nine PTFE grafts (44%) and two of nine Dacron (22%) replacement grafts (p greater than 0.05). Prosthetic replacement of Dacron prostheses infected by S. epidermidis as a bacteria-laden surface biofilm can result in early graft healing, but persistent colonization of one third of replacement grafts signify that recurrent clinical infection remains a risk.
建立了一种犬类模型，以研究移植物置换作为治疗表皮葡萄球菌引起的血管假体感染的疗效。通过植入在体外被产黏液表皮葡萄球菌菌株定植的涤纶假体，在18只犬中建立肾下腹主动脉移植物感染，以形成附着有细菌的生物膜（5×10⁶集落形成单位/平方厘米移植物）。研究动物发生了具有人类晚期人工移植物感染典型解剖学和微生物学特征的移植物感染（移植物周围无菌渗出液、移植物未融合、血清白细胞计数和血沉率正常）。通过机械破坏移植物表面生物膜并在肉汤培养基中培养，从18个取出的移植物中的14个（78%）分离出表皮葡萄球菌研究菌株。4只移植物培养无菌的犬有细菌感染的组织学证据。通过移植物切除、静脉注射头孢唑林以及用涤纶或聚四氟乙烯（PTFE）血管假体置换移植物，治疗已建立的假体表面生物膜感染。移植物置换1个月后，没有PTFE移植物有感染迹象，但9个涤纶移植物中有3个（33%）出现移植物周围渗出液和炎症。从9个PTFE移植物中的4个（44%）和9个涤纶置换移植物中的2个（22%）中分离出研究菌株（p>0.05）。用涤纶假体置换被表皮葡萄球菌感染形成含细菌表面生物膜的假体可导致移植物早期愈合，但三分之一的置换移植物持续定植表明复发性临床感染仍然是一种风险。
