Department of Orthopaedics, Chinese PLA General Hospital, No. 28 Fuxing Road, Beijing 100853, China.
Medical College, Nankai University, No. 94 Weijin Road, Tianjin 300071, China.
Biomed Res Int. 2017;2017:9146317. doi: 10.1155/2017/9146317. Epub 2017 Oct 10.
The aim of this study is to evaluate the effectiveness of laboratory serum tests in the diagnosis of infected nonunion.
Forty-two patients suspected of having infected nonunion were investigated in the study. The serum levels of white blood-cell count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and interleukin-6 (IL-6) were measured. A positive diagnosis of infection was made on the basis of the positive culture results. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each test were calculated.
The sensitivity and specificity of CRP both were higher than IL-6: 60.0% versus 57.1% and 85.7% versus 57.1%, respectively. With one, two, three, and four positive tests, the predicted probabilities of infection were 66.7%, 90.9%, 100%, and 100%, respectively, but the number of patients who had three or four positive tests was small.
The diagnostic utility of IL-6 is inferior to CRP and the finding conflicts with previous conclusions drawn from periprosthetic infections. Laboratory analysis of serum inflammatory markers alone is not an effective screening tool for patients suspected of having an infected nonunion.
本研究旨在评估实验室血清检测在诊断感染性骨不连中的有效性。
本研究纳入了 42 例疑似感染性骨不连的患者。检测了白细胞计数（WBC）、C 反应蛋白（CRP）、红细胞沉降率（ESR）和白细胞介素 6（IL-6）的血清水平。基于阳性培养结果做出感染的阳性诊断。计算了每种检测的敏感性、特异性、阳性预测值（PPV）和阴性预测值（NPV）。
CRP 的敏感性和特异性均高于 IL-6：60.0% 对 57.1%和 85.7% 对 57.1%。一项、两项、三项和四项检测均为阳性时，感染的预测概率分别为 66.7%、90.9%、100%和 100%，但有三项或四项检测阳性的患者数量较少。
IL-6 的诊断效用不及 CRP，这与先前从假体周围感染得出的结论相矛盾。单独检测血清炎症标志物不能作为疑似感染性骨不连患者的有效筛查工具。
