犬脊柱化脓性感染模型的建立

Establishment of a dog model of pyogenic spinal infection

背景:脊柱感染模型在文献中鲜有报道,对脊柱感染动物模型的影像学及组织学观察报道就更少。目的:建立一种新型的犬脊柱化脓性感染模型。方法:取中国杂种家犬12只。动物取右侧卧位,手术入路选择腹膜后入路,手术暴露动物脊柱T12/L1椎间隙,将暴露椎间隙的椎间盘部分切除,用刮匙破坏椎间隙相邻的上下节段椎体终板,然后将含有不同浓度的金黄色葡萄球菌的悬浮液和硬化剂鱼肝油酸钠注射入犬的脊柱椎间隙。切除部分椎间盘并破坏椎体终板的目的是使椎体骨组织更好的与细菌相接触。对动物脊柱L5/6间隙完成同样操作。动物在术后14 d处死,感染的椎间盘及其相邻椎体取出,对取出标本的细菌含量进行定量测定。处死时取部分肝脏组织和抽血进行细菌培养,观测是否有全身系统性感染的发生。结果与结论:(1)成功的应用金黄色葡萄球菌浓度为102 CFU/m L的细菌悬浮液在90%(9/10)的接种部位中诱导出脊柱感染。肝脏组织及血液培养结果均呈阴性,排除了全身系统性感染的可能;(2)接种细菌浓度高于103CFU/m L的4只动物中有2只在术后3 d内死亡;(3)结果提示,成功建立了一种新型犬脊柱化脓性感染模型,这种模型可以广泛地应用于验证不同抗感染治疗方法的疗效。

BACKGROUND： Spine infection models are rarely reported in the literature. There are fewer reports on the imaging and histological observations of the animal model of spinal infection. OBJECTIVE： To develop a canine model of pyogenic spinal infection. METHODS： Twelve Chinese dogs were adopted in the study. The dogs were in the right arm recumbent. The surgery was conducted by retroperitoneal approach to expose T12/L1 intervertebral space. The intervertebral discs that exposed the intervertebral space were partially removed, and the end plate of the adjacent two vertebrae was deliberately curetted out. Suspension with different concentrations of Staphylococcus aureus and sodium morrhuate were injected into the dog intervertebral space. The aim of removal of partial intervertebral discs and destruction of endplate was to make the vertebral body bone better in contact with the bacteria. The same operation was conducted in L5/6 clearance of the animal spine. At 14 days after surgery, animals were sacrificed. The infected intervertebral disc and adjacent vertebral bodies were taken out. Bacterial contents of specimens were quantitatively determined. During sacrificing, partial liver tissues and blood samples were collected for bacterial culture. The occurrence of systemic infection was observed. RESULTS AND CONCLUSION：（1） Spondylodiscitis of the lumbar spinal column was consistently produced in 90%（9/10） the sites challenged with 102 colony-forming units（CFU） Staphylococcus aureus. Liver biopsy and blood culture did not show any signs of systematic infections.（2） Two out of four animals implanted the suspension with a concentration higher than 103 CFUs died within 3 days post-implantation.（3） These results suggested that a new canine model of pyogenic spinal infection was developed. This model could be used to test the efficacy of different anti-infection strategies.