Background

Serum immune markers can be useful in the diagnosis of periprosthetic joint infection (PJI) by detecting long-lasting abnormal immunological conditions. The purpose of this study was to examine whether serum immune markers can improve the diagnostic accuracy of PJI.

Methods

We enrolled 51 PJI, 45 aseptic loosening, and 334 osteoarthritis patients for assessment of the discriminatory accuracy of serum markers including white blood cell count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and D-dimer, total protein, albumin (Alb), globulin (Glb), neutrophil-lymphocyte ratio, lymphocyte-monocyte ratio, platelet-lymphocyte ratio, albumin-globulin ratio (AGR), CRP-albumin ratio (CAR), and CRP-AGR ratio (CAGR). These diagnostic accuracies for low-grade PJI were also calculated in patients who had serum CRP levels < 10 mg/L.

Results

Among serum markers, Alb, Glb, AGR, CRP, ESR, CAR, and CAGR had highly accurate diagnostic accuracy for PJI, with area under the curve of 0.92, 0.90, 0.96, 0.97, 0.92, 0.97, and 0.98, respectively. In low-grade PJI patients, area under the curve of CRP, ESR, CAR, and CAGR (0.69, 0.80, 0.65, and 0.82, respectively) was decreased but that of Alb, Glb, and AGR (0.90, 0.88, and 0.95, respectively) remained high, indicating the diagnostic utility of these immune markers. The sensitivity and specificity of AGR with cutoff value of 1.1 were demonstrated as 0.92 and 0.89, respectively, and with cutoff value of 1.2, 1.00, and 0.79, respectively, in the diagnosis of low-grade infection.

Conclusion

Our results demonstrate the potential value of Alb, Glb, AGR, and combination indices of these immune makers with CRP in improving preoperative serum diagnosis for PJI, especially in low-grade PJI.

Level of Evidence

Diagnostic- Level II.

中文翻译：

---

血清白蛋白和球蛋白联合 C 反应蛋白的评估提高了低级别假体周围关节感染的血清诊断准确性

背景

血清免疫标记物可用于通过检测长期异常的免疫状况来诊断假体周围关节感染 (PJI)。本研究的目的是检验血清免疫标志物是否可以提高 PJI 的诊断准确性。

方法

我们招募了 51 名 PJI、45 名无菌性松动和 334 名骨关节炎患者，以评估血清标志物的鉴别准确性，包括白细胞计数、C 反应蛋白 (CRP)、红细胞沉降率 (ESR) 和 D-二聚体、总蛋白、白蛋白 (Alb)、球蛋白 (Glb)、中性粒细胞-淋巴细胞比率、淋巴细胞-单核细胞比率、血小板-淋巴细胞比率、白蛋白-球蛋白比率 (AGR)、CRP-白蛋白比率 (CAR) 和 CRP-AGR 比率 (CAGR) . 这些对低级别 PJI 的诊断准确性也在血清 CRP 水平 < 10 mg/L 的患者中进行了计算。

结果

血清标志物中，Alb、Glb、AGR、CRP、ESR、CAR、CAGR对PJI的诊断准确率较高，曲线下面积分别为0.92、0.90、0.96、0.97、0.92、0.97、0.98。在低级别 PJI 患者中，CRP、ESR、CAR 和 CAGR（分别为 0.69、0.80、0.65 和 0.82）的曲线下面积有所下降，但 Alb、Glb 和 AGR 的曲线下面积（分别为 0.90、0.88 和 0.95 ，分别）仍然很高，表明这些免疫标记物的诊断效用。诊断低度感染时，截断值为 1.1 的 AGR 的敏感性和特异性分别为 0.92 和 0.89，截断值为 1.2、1.00 和 0.79 时的敏感性和特异性分别为 0.92 和 0.89。

结论

我们的结果证明了 Alb、Glb、AGR 以及这些免疫标记物与 CRP 的组合指标在改善 PJI 术前血清诊断方面的潜在价值，尤其是在低级别 PJI 中。

证据等级

诊断级 II。