Ulphani J S, Rupp M E
University of Nebraska Medical Center, Omaha, USA.
Lab Anim Sci. 1999 Jun;49(3):283-7.
Staphylococcus aureus is an important cause of intravascular catheter-associated bacteremia. We developed a rat central venous catheter (CVC)-associated infection model to study pathogenesis and treatment.
A silastic lumen-within-lumen catheter and rodent-restraint jacket were designed. Subcutaneously tunneled catheters were inserted in the jugular vein of 20 male Sprague Dawley rats. Twelve rats (group 1) were inoculated with S. aureus via the CVC; three rats (group 2) were inoculated with S. aureus via the tail vein, five rats (group 3) served as uninfected controls; and three rats (group 4) were inoculated with S. aureus via the tail vein but did not undergo CVC insertion. Five to eight days after inoculation, animals were euthanized, CVCs were aseptically removed, and quantitative culture was done. Quantitative culture also was performed on blood, heart, liver, lungs, and kidneys.
Infection, characterized by bacteremia and metastatic disease, was observed in all rats inoculated via the CVC with as few as 100 colony-forming units (CFU) of S. aureus. Rats of group 2 were not as likely to develop CVC-associated infection, and none of the animals of groups 3 or 4 developed infection.
This model of CVC-associated infection should prove suitable for studying pathogenesis and treatment of the condition.
金黄色葡萄球菌是血管内导管相关菌血症的重要病因。我们建立了大鼠中心静脉导管（CVC）相关感染模型以研究其发病机制和治疗方法。
设计了一种双腔硅橡胶导管和啮齿动物约束外套。将皮下隧道式导管插入20只雄性Sprague Dawley大鼠的颈静脉。12只大鼠（第1组）通过CVC接种金黄色葡萄球菌；3只大鼠（第2组）通过尾静脉接种金黄色葡萄球菌，5只大鼠（第3组）作为未感染对照；3只大鼠（第4组）通过尾静脉接种金黄色葡萄球菌但未插入CVC。接种后5至8天，对动物实施安乐死，无菌取出CVC并进行定量培养。同时对血液、心脏、肝脏、肺和肾脏进行定量培养。
在所有通过CVC接种低至100个金黄色葡萄球菌菌落形成单位（CFU）的大鼠中均观察到以菌血症和转移性疾病为特征的感染。第2组大鼠发生CVC相关感染的可能性较小，第3组或第4组动物均未发生感染。
这种CVC相关感染模型应适用于研究该疾病的发病机制和治疗方法。
