C反应蛋白、白介素-6及白细胞计数在兔膝关节置换术后早期感染诊断中的应用

The application of C-reactive protein,leukocyte and IL-6 in the diagnosis of early infection after knee arthroplasty in rabbit

目的:探讨关节液中C反应蛋白(C reactive protein,CRP)、外周血白细胞(white blood cell,WBC)计数以及血清白细胞介素-6(interleukin-6,IL-6)在关节假体周围感染早期诊断中的意义。方法:选取18只健康家兔进行左膝关节置换术,采用钛合金指骨螺钉作为关节置换假体,感染组家兔在关节腔中注射金黄色葡萄球菌液,对照组注入等量的生理盐水。检测所有家兔关节液CRP、外周血WBC计数以及血浆IL-6含量变化。术后2周行关节腔中滑膜及假体周围组织细菌学检查。结果:细菌培养可见感染组金黄色葡萄球菌阳性,而对照组为阴性;与手术当天相比,对照组术后1 d、术后3 d外周血WBC计数、血清IL-6水平、关节液CRP水平均升高(P<0.05),而感染组各时间段WBC计数、血清IL-6水平、关节液CRP水平均高于同期对照组(P<0.05)。结论:检测膝关节感染模型术后外周血WBC计数、血清IL-6及关节液中CRP指标的变化,可为临床人工关节置换术后早期感染的诊断提供一定帮助。

Objective： To evaluate the diagnostic value of the changes of C - reactive protein, white blood cell and interleukin - 6 （ IL - 6） in early infection after knee arthroplasty in rabbit. Methods： Left knee arthroplasty was performed in 18 New Zealand white rabbits selected with tita- nium alloy screws as knee replacement prosthesis during the surgery. And articular cavites of the rabbits in the infection group were injected with Staphylococcus aureus fluid while the control group was injected with the same amount of saline. After the operation, the changes of CRP in joint fluid, peripheral blood WBC counts and plasma IL -6 levels in all rabbits were observed respectively. Results： Bacterial infection group were posi- tive for Staphylococcus aureus, while the control group was negative. Compared with the statistics on the day of surgery, postoperative 1 d and 3d peripheral blood WBC counts, serum IL - 6 level, and CRP level in synovial fluid in the control group were increased （ P 〈 0.05 ）. The WBC counts, the level of serum IL - 6, and CRP level in synovial fluid at different time in the infection group were higher than those of the control group （ P 〈 0.05 ）. Conclusion： The detection for the changes of peripheral blood WBC count, serum IL -6 and CRP indexes in the postoperative joint fluid of the knee joint infection model can provide some help for the diagnosis of early infection after artificial joint replacement.